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Background

Electronic cigarettes (ECs) and heat-not-burn (HNB) devices are relatively new products that are increasingly used alternatively or complementary to ordinary tobacco products.

Objectives

To analyse current data from the German Study on Tobacco Use (DEBRA) regarding the prevalence of EC and HNB device use and associated socioeconomic factors and smoking behaviour; compare reasons for EC use between adolescents and adults; describe the self-perceived risk of HNB devices.

Material and methods

DEBRA is an ongoing, representative, face-to-face household survey of the population aged 14 years and older. We analysed data from the first nine waves (June/July 2016 to October/November 2017; n?=?18,415) for the current study.

Results

During the observation period, 1.9% (95% confidence interval (CI)?=?1.7–2.2%) of the German population used ECs (2.8% of the 14- to17-year-olds) and 74.5% (95% CI?=?69.4–79.2%) of current EC users also smoked tobacco (“dual use”). Three-quarters of adolescents used ECs mainly “for fun”, whereas reasons for use among adults related more to smoking tobacco (e.?g., less harmful, to quit smoking). Among current smokers and recent ex-smokers (<12 months smoke-free), 0.3% (95% CI?=?0.09–0.64%) currently used HNB devices, and 6.0% (95% CI?=?5.0–7.2%) had ever used them. Consumption of HNB products increased with increasing education and income. The majority perceived HNB products as somewhat (41.0%, n?=?25) or much (14.8%, n?=?9) less harmful, and 37.7% (n?=?23) as equally harmful compared with tobacco cigarettes.

Conclusions

In Germany, ECs are mainly consumed as “dual use” together with tobacco. Consumption of HNB products currently occurs at a very low rate and is relatively more common among smokers with higher education and income. It remains important to monitor the use of new electronic inhalation products in the total population and in relevant subgroups.
  相似文献   
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We investigated the brain regions that mediate the processing of emotional speech in men and women by presenting positive and negative words that were spoken with happy or angry prosody. Hence, emotional prosody and word valence were either congruous or incongruous. We assumed that an fRMI contrast between congruous and incongruous presentations would reveal the structures that mediate the interaction of emotional prosody and word valence. The left inferior frontal gyrus (IFG) was more strongly activated in incongruous as compared to congruous trials. This difference in IFG activity was significantly larger in women than in men. Moreover, the congruence effect was significant in women whereas it only appeared as a tendency in men. As the left IFG has been repeatedly implicated in semantic processing, these findings are taken as evidence that semantic processing in women is more susceptible to influences from emotional prosody than is semantic processing in men. Moreover, the present data suggest that the left IFG mediates increased semantic processing demands imposed by an incongruence between emotional prosody and word valence.  相似文献   
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Endotoxin is a component of gram-negative bacteria that causes hematologic and immunologic changes through its induction of cytokines. Interleukin-1 receptor antagonist (IL-1Ra) is a naturally occurring inhibitor of IL-1 that competes with IL-1 for occupancy of cell-surface receptors but possesses no agonist activity. We investigated the ability of human recombinant IL-1Ra to block the effects of low-dose endotoxin. Fourteen healthy male volunteers between 18 and 30 years old were injected intravenously with 3 ng/kg Escherichia coli endotoxin. Concurrent with the injections, nine volunteers received a 3-hour continuous intravenous infusion of IL-1Ra. The other five subjects were given a 3-hour infusion of saline. Volunteers injected with endotoxin experienced a threefold increase in circulating neutrophils over baseline. This neutrophilia was significantly reduced by 48% in subjects administered endotoxin plus IL-1Ra (P = .0253). Ex vivo mitogen-induced peripheral blood mononuclear cell proliferation decreased by greater than 60% at 3 and 6 hours after endotoxin injection (P = .0053). This endotoxin-induced reduction in mitogen response was reversed in subjects coinjected with IL-1Ra (P = .0253). Endotoxin-induced symptoms, fever, and tachycardia were unaffected by IL-1Ra. IL-1 appears to be an important mediator in endotoxemia because some of its hematologic and immunomodulatory effects can be blocked by IL-1Ra.  相似文献   
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Noorman  F; Braat  EA; Rijken  DC 《Blood》1995,86(9):3421-3427
The balance of tissue-type plasminogen activator (t-PA) production and degradation determines its concentration in blood and tissues. Disturbance of this balance may result in either increased or decreased proteolysis. In the present study, we identified the receptor systems involved in the degradation of t-PA by human monocytes/macrophages in culture. Monocytes were cultured and became macrophages within 2 days. At 4 degrees C, 125I-t-PA bound to macrophages with high (apparent dissociation constant [kd], 1 to 5 nmol/L) and low affinity (kd > 350 nmol/L). At 37 degrees C, the cells internalized and degraded t-PA via the high affinity binding sites, which were partially inhibited by mannan. The low affinity binding sites were 6-aminohexanoic acid- inhibitable and not involved in t-PA degradation. Degradation of t-PA was upregulated during differentiation of monocytes to macrophages. Dexamethasone further upregulated the mannan-inhibitable t-PA degradation. Lipopolysaccharide downregulated both mannan-inhibitable and non-mannan-inhibitable t-PA degradation. Non-mannan-inhibitable degradation was completely blocked by recombinant 39-kD receptor- associated protein (RAP, inhibitor of lipoprotein receptor-related protein [LRP]), whereas mannan-inhibitable degradation was blocked by the addition of a monoclonal antibody against the mannose receptor. No differences between the degradation of t-PA and functionally inactivated t-PA were observed. We conclude that human monocyte-derived macrophages are able to bind, internalize, and degrade t-PA. Degradation of t-PA does not require complex formation with plasminogen activator inhibitors. The macrophages use two independently regulated receptors, namely, the mannose receptor and LRP, for the uptake and degradation of t-PA.  相似文献   
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Systemic non‐biologic agents have long been in clinical use in medicine – often with considerable efficacy, albeit with some adverse effects – as with all medications. With the advent of biologic agents, all of which currently are restricted to systemic use, there is a growing need to ensure which agents have the better therapeutic ratio. The non‐biologic agents (NBAs) include a range of agents, most especially the corticosteroids (corticosteroids). This study reviews the corticosteroids in systemic use in management of orofacial mucocutaneous diseases; subsequent studies discuss corticosteroid‐sparing agents used in the management of orofacial diseases, such as calcineurin inhibitors used to produce immunosuppression; purine synthetase inhibitors; and cytotoxic and other immunomodulatory agents.  相似文献   
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