Silver acetate interactions with nicotine and non-nicotine smoke components.

Oral topical silver-containing formulations were marketed in the 1970s and 1980s as smoking deterrents, based on the finding that when using such formulations, an unpleasant taste occurs upon smoking. This approach has not been widely adopted, however, in part because of a lack of efficacy data. The advent of new pharmacologic treatments for smoking cessation renews the possibility that such a taste aversion approach may be a useful adjunct to smoking cessation treatment. This study explored the basic mechanistic question of whether topical oral silver acetate solution interacts with nicotine as opposed to non-nicotine smoke constituents. We recruited 20 smoking volunteers to rate nicotine-containing or denicotinized cigarettes, as well as the Nicotrol nicotine vapor inhaler and sham (air) puffs. In two sessions, subjects rated the sensory and hedonic qualities of puffs after rinsing their mouths with either silver acetate solution or deionized water (placebo). Silver acetate relative to placebo solution substantially reduced liking and satisfaction ratings for the usual brand and denicotinized cigarettes; in contrast, for the nicotine inhaler these ratings were unaffected by the silver-based treatment. These results support the conclusion that silver acetate not only renders the taste of cigarette smoke less appealing, but also that the compound appears to interact selectively with non-nicotine smoke constituents. Moreover, these data suggest silver acetate would be compatible with buccal nicotine delivery systems (e.g., nicotine lozenge or gum). Combined use of taste aversion with nicotine replacement therapy could provide the smoker with additional assistance to resist relapse. Further exploration is warranted of the use of silver-based preparations as a short-term adjunct to smoking cessation treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dose released and absolute bioavailability of nicotine from a nicotine vapor inhaler

In an open, randomized, three-way crossover study, 14 healthy smokers used one type of nicotine vapor inhaler intensely for 20 minutes every hour for 11 hours (12 administrations). Two different inhalation techniques were applied, shallow frequent sucking (buccal mode) and deep inhalations (pulmonary mode). The determination of nicotine was performed by capillary gas chromatography after single-step liquid-liquid extraction of the plasma sample. Nicotine was detected by means of a nitrogen-sensitive detector, giving high selectivity and sensitivity. The mean (+/- SD) nicotine dose released from each nicotine vapor inhaler unit was estimated at 4.00 +/- 0.60 mg (buccal mode) and 3.87 +/- 0.75 mg (pulmonary mode), inhaled with approximately 15 L of air. Mean (+/- SD) peak plasma level of the last dosing interval was 32.0 +/- 8.7 ng/ml and 34.2 +/- 8.9 ng/ml for the buccal and the pulmonary technique, respectively, achieved after 0.33 and 0.50 (median) hour, respectively. The mean (95% confidence interval [CI]) absolute bioavailability of nicotine was 51 (95% CI, 40 to 65) and 56 (95% CI, 47 to 67) when the buccal and pulmonary techniques were used, respectively. A significant correlation was found between systemically available dose and average steady-state nicotine plasma concentration. Based on the achievement of similar nicotine plasma levels, it may be concluded that the two modes of inhalation appear to be clinically equivalent.     

The influence of caffeine on nicotine's discriminative stimulus, subjective, and reinforcing effects.

Caffeine may acutely alter the discriminative stimulus and subjective effects of nicotine, perhaps explaining the association of coffee intake with smoking status. In this study, smokers were initially trained to discriminate 20 μg/kg nicotine by nasal spray from placebo (0). Then, generalization of nicotine discrimination was tested, using both 2- and 3-choice ("novel" option) procedures, across a range of doses (0-20 μg/kg) following pretreatment with 0, 2.5, and 5.0 mg/kg caffeine p.o. Nicotine reinforcement was assessed after the end of generalization testing using a choice procedure. Caffeine pretreatment did not alter nicotine discrimination and self-administration. Caffeine and nicotine influenced some subjective and cardiovascular responses, but there were no interaction effects except for diastolic blood pressure. These results do not support the notion that caffeine acutely alters nicotine's discriminative stimulus, subjective, or reinforcing effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The nicotine inhaler in smoking cessation

BACKGROUND: Nicotine replacement therapy has been shown to improve success rates in smoking cessation treatment. However, the available products cause adverse effects, which prevent some smokers from using them. A new method of delivering nicotine via inhaler supplies nicotine orally through inhalation from a plastic tube. This mode of delivering nicotine resembles smoking, as it includes handling and active inhalation. OBJECTIVES: To assess the efficacy and safety of the nicotine inhaler as an aid in smoking cessation. METHODS: A 1-year, randomized, double-blind, placebo-controlled study was conducted in a smoking cessation clinic. Two hundred forty-seven smokers who smoked at least 10 cigarettes per day and who had previously made a serious attempt to stop smoking using nicotine chewing gum were recruited through advertisements. Randomization to treatment or control conditions were made at the first group session, with 123 participants receiving nicotine inhalers and 124 receiving placebo inhalers. The inhalers were distributed at the second session and participants were allowed to use the inhalers for 6 months. MAIN OUTCOME MEASURE: Biochemically verified continuous abstinence from smoking after 2 and 6 weeks and at 3, 6, and 12 months. RESULTS: Significantly more participants who had used the nicotine inhalers were continuously abstinent compared with those who had used the placebo inhalers. The respective success rates after 12 months were 28% and 18% (P = .046). At 6 months, 20 participants (16%) in the nicotine group were still using the inhaler, compared with 4 (3%) in the control group (P < .001). CONCLUSION: The nicotine inhaler was an effective smoking cessation aid that produced a few mild and transient adverse effects.     

Low-dose nicotine nasal spray use and effects during initial smoking cessation.

The purposes of this study were to determine if smokers wanting to quit smoking would use a low-dose nicotine nasal spray (i.e., acceptability) and what effect this spray use would have on withdrawal during the 1st week of cessation. Smokers (n?=? 52) were assigned double-blind to either placebo or nicotine spray (1.5 μg/kg. or approx. 0.1 mg, per spray) for ad lib use during the first week of cessation. All received group behavioral counseling. There was no difference in continuous 1-week abstinence (daily COa?     

Identifying individuals with high fat levels and low P:S ratios, in their diets, for intensive dietary intervention

OBJECTIVE: Interindividual variability in plasma concentrations of nicotine and its proximate metabolite, cotinine, is considerable during smoking and transdermal nicotine treatment, even among individuals taking in nominally similar doses of nicotine. This report explores the determinants of this variability and the utility of baseline (smoking) plasma concentrations to predict concentrations during transdermal nicotine treatment. METHODS: Data were analysed from a smoking cessation study (n = 466), and from a pharmacokinetic study (n = 12). Multiple regression models examined the relationships of plasma concentrations to individual characteristics such as smoking pattern, absorbed dose of nicotine, and pharmacokinetic parameters. RESULTS: Plasma concentrations of nicotine and cotinine were highly variable in both studies. Indirect estimates of plasma clearance (baseline plasma concentration divided by cigarettes per day) together with other factors could account for 18 to 33% of the variability during transdermal nicotine treatment in the smoking cessation study. In contrast, 75 to 99% was accounted for by direct measurements of plasma clearances and systemic dose of nicotine in the pharmacokinetic study. CONCLUSION: Plasma concentrations of nicotine and cotinine during transdermal nicotine treatment are poorly predicted by clinical history or baseline plasma concentrations. This is a result of inadequate characterisation of highly variable individual pharmacokinetic parameters and absorbed dose of nicotine. Considering the interindividual variability of plasma nicotine and cotinine concentrations together with the lack of clinical end-points for transdermal nicotine dosing, it seems logical to investigate the utility of a therapeutic drug monitoring approach for transdermal nicotine treatment-particularly for high dose regimens (> 22 mg per 24 hours).     

Amphetamine lowers brain stimulation reward (BSR) threshold in alcohol-preferring (P) and non-preferring (NP) rats: Regulation by D? and D? receptors in the nucleus accumbens.

Differences in the mesolimbic dopamine (DA) pathway that regulates alcohol preference may also increase sensitivity to the reinforcing effects of other drugs of abuse. In the present study, the curve-shift (rate-frequency) paradigm was used to quantify the interaction of amphetamine with the rewarding effects of lateral hypothalamic brain stimulation reward (BSR) in alcohol-preferring (P) and -nonpreferring (NP) rats. The role of D? and D? DA receptors of the nucleus accumbens (NAcc) in mediating the reward-potentiating effects of amphetamine was also determined. Animals were tested with randomly administered amphetamine (0.25, 0.75, 1.25 mg/kg ip), DA-receptor antagonists (SCH 23390 [2.0 μg, 5.0 μg]; eticlopride [2.0 μg, 5.0 μg]), or a combination of the 2 (SCH 23390 [2.0 μg, 5.0 μg] + 0.75 mg/kg amphetamine; eticlopride [2.0 μg, 5.0 μg] + 0.75 mg/kg amphetamine). Amphetamine produced comparable dose-related leftward shifts in the rate-frequency function for both P and NP rats, with a greater than 60% reduction observed in BSR threshold. On intervening days, baseline threshold was unaltered between tests and similar between rat lines. Unilateral infusion in the NAcc of either the D? or D? receptor antagonist produced rightward shifts in the rate-frequency function of amphetamine, completely reversing-attenuating its reward-enhancing effects. The results demonstrate that amphetamine produces similar threshold-lowering effects in both P and NP rats and that the reward-potentiating effects of amphetamine do not correlate with alcohol preference under the conditions of the present study. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Chronic voluntary nicotine drinking enhances nicotine palatability in rats.

Examined the response of rats to nicotine (NI) solutions with the brief-exposure, taste reactivity (TR) test, and a 2-bottle, 24-hr preference test. Naive nondeprived Ss were administered intraoral infusions of distilled water and 1 μg/ml, 5 μg/ml, 10 μg/ml, 25 μg/ml, 50 μg/ml, and 100 μg/ml NI. NI solutions up to a concentration of 50 μg/ml elicited a number of ingestive TR responses similar to that by water. Ingestive responses significantly decreased and aversive TR responses significantly increased in response to 100 μg/ml nicotine. On the basis of these results, 2-bottle preferences for water vs 1 μg/ml, 5 μg/ml, and 0 μg/ml (water control group) NI were measured in 3 groups of naive Ss. Ss initially showed an equal preference for 0 μg/ml and 1 μg/ml NI. After 16 days of exposure, however, Ss developed a significant preference for 1 μg/ml NI. The preference ratio for 5 μg/ml NI significantly increased during the experiment, but the preference ratio remained significantly less than that for 1 μg/ml and 0 μg/ml NI solutions. Last, TR responses elicited by intraoral infusions of 1 μg/ml and 5 μg/ml NI were then measured in these Ss having had the 2-bottle experience. Ss showing a 2-bottle preference for the 1 μg/ml NI solution displayed significantly more ingestive TR responses to 1 μg/ml and 5 μg/ml NI than did the control Ss. Data indicate that prolonged voluntary access to NI results in an increased preference for NI and modifies the immediate oral/gustatory reactivity of the Ss to NI. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The influence of nicotine dose and nicotine dose expectancy on the cognitive and subjective effects of cigarette smoking.

This study investigated the independent and interactive effects of nicotine dose and nicotine dose expectancy on smoking outcomes using a 2 (given nicotine vs. placebo) × 2 (told nicotine vs. placebo) Balanced Placebo Design (BPD). Smokers (N = 148) completed the Rapid Visual Information Processing Task (RVIP) and measures of smoking urge, mood, and cigarette ratings (e.g., satisfying) after smoking a nicotine or placebo cigarette crossed with instructions that the cigarette contained either nicotine or no nicotine. Nicotine cigarettes (0.6 mg nicotine) produced better sustained attention performance than placebos as indicated by RVIP reaction time, hits, and sensitivity (A′). Nicotine cigarettes also produced better mood and greater rewarding subjective effects of the cigarettes on 11 of 11 dimensions compared to placebos. Nicotine instructions resulted in fewer RVIP false alarms, better mood, and greater rewarding subjective effects of the cigarettes on 9 of 11 dimensions compared to placebo instructions. Nicotine dose by nicotine dose expectancy interactions were also observed for urge and tension-anxiety, such that the dose expectancy manipulation produced differential effects only among those who smoked placebo cigarettes. In contrast a significant interaction for self-reported vigor-activity demonstrated that the dose expectancy manipulation produced effects only among those who smoked nicotine cigarettes. This study provides additional evidence that nicotine improves cognitive performance, and provides initial evidence that denicotinized cigarettes smoked under the guise that they contain nicotine influence cognitive performance, albeit with less robust effects than nicotine. These data may inform the development of expectancy-based interventions for tobacco dependence. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Greater sensitivity to subjective effects of nicotine in nonsmokers high in sensation seeking.

The personality characteristic of sensation seeking is associated with risk of smoking, perhaps because of greater initial sensitivity to nicotine. Young healthy nonsmokers (N?=?37) were administered 0, 10, and 20 μg/kg nicotine by nasal spray in 3 separate sessions, and subjective responses were assessed. Sensation-Seeking Scale (SSS) scores were then correlated with these responses. A comparison group of smokers (N?=?55) was included to determine whether sensation seeking was associated specifically with initial sensitivity to nicotine or with general sensitivity regardless of past nicotine exposure. SSS subscales, particularly Experience Seeking and Disinhibition, were correlated with subjective responses to nicotine in nonsmokers but generally not in smokers. These findings indicate that sensation seeking is associated with greater initial sensitivity to nicotine's subjective effects and may provide directions for further study of individual-differences characteristics that predispose people to the risk of becoming smokers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The separate and combined effects of nicotine and alcohol on working memory capacity in nonabstinent smokers.

Research indicates that nicotine and alcohol are often used on the same occasion. However, the reasons for their concurrent use are not well understood. We hypothesized that one reason smokers use tobacco when they drink alcohol is to compensate for alcohol’s negative effects on processing capacity with nicotine’s enhancement of processing capacity. As such, the present study tested this theory by using an independent groups design to examine the separate and combined acute effects of alcohol and nicotine on working memory (WM) capacity. Nonabstinent daily smokers (n = 127) performed the counting span task (CSPAN) after consuming either an alcohol (men: 0.8 g/kg; women: 0.7 g/kg) or placebo beverage and smoking either nicotinized (1.14 mg nicotine, 15.9 mg tar) or denicotinized (.06 mg nicotine, 17.9 mg tar) cigarettes. Analyses revealed that smokers who smoked the nicotinized cigarettes performed significantly worse on the CSPAN task than smokers who smoked the denicotinized cigarettes. Although there was no main effect of alcohol on WM performance, women exhibited better WM performance than men after consuming alcohol whereas men performed better than women on the WM task after consuming the placebo beverage. Findings also revealed no interaction between the two substances on WM performance. Taken together, results suggest that nicotine impairs nonabstinent smokers’ verbal WM capacity and that gender moderates the effects of alcohol on WM. Furthermore, the present findings failed to support the notion that nicotine compensates for alcohol-related decrements in working memory capacity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Compensatory nicotine self-administration in rats during reduced access to nicotine: An animal model of smoking reduction.

The ability of smoking reduction (e.g., decreasing cigarettes per day) to produce significant reductions in toxin exposure is limited by compensatory increases in smoking behavior. Characterizing factors contributing to the marked individual variability in compensation may be useful for understanding this phenomenon. The goal of the current study was to develop an animal model of smoking reduction and to begin to examine potential behavioral and pharmacokinetic contributors to compensation. Rats trained for nicotine self-administration (NSA) in unlimited access sessions were exposed to a progressive decrease in duration of access to nicotine from 23-hr/day to 10-, 6-, and 2-hr/day. Following a return to 23 hr/day access and extinction, single-dose nicotine pharmacokinetic parameters were determined. Rats exhibited a reduction in total daily nicotine intake during reduced access to NSA, but decreases in nicotine intake were not proportional to decreases in access duration. Compensatory increases in hourly infusion rate were also observed when access was decreased. The magnitude of compensation differed considerably among animals. Early session infusion rate during baseline was significantly correlated, while nicotine clearance was moderately correlated, with 1 measure of compensation. Infusion rates were transiently increased compared to prereduction levels when unlimited access was restored, and this effect was greatest in animals that had exhibited the greatest levels of compensation. These findings indicate that rats exhibit compensatory increases in NSA during reduced access to nicotine, with substantial individual variability. This model may be useful for characterizing underlying factors and potential consequences of compensatory smoking. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of Transdermal Nicotine During Imaginal Exposure to Anxiety and Smoking Cues in College Smokers.

In a 2 (patch) × 2 (smoking) × 2 (anxiety) mixed design, 52 undergraduate smokers randomly received a nicotine (21 mg) or placebo patch. After a 4-hr nicotine absorption/deprivation period, participants imagined several scenarios varying in cue content: (a) anxiety plus smoking, (b) anxiety, (c) smoking, and (d) neutral. Although smoking urge increased in both the nicotine and placebo conditions after the absorption/deprivation period, those who received the placebo reported significantly greater urge. During the cue reactivity trials, a significant Patch × Smoking × Anxiety interaction effect was observed for urge. However, participants who received nicotine still experienced moderate urges, indicating that nicotine did not attenuate cue-elicited urge. Transdermal nicotine did not diminish anxiety during the absorption/deprivation period or in response to the cues. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of chronic nicotine treatment and withdrawal on hypothalamic proopiomelanocortin gene expression and neuroendocrine regulation

Considerable evidence suggest that some responses to smoking and nicotine are mediated by forebrain beta-endorphinergic opioid mechanisms. It has also been demonstrated that nicotine stimulates rat tuberoinfundibular dopaminergic activity. Since we have proposed that interactions between mediobasohypothalamic (MBH) dopaminergic and beta-endorphinergic mechanisms have a key role in neuroendocrine integration, we investigated the effects of chronic nicotine treatment and withdrawal on: (1) MBH concentrations of proopiomelanocortin (POMC, precursor for beta-endorphin biosynthesis) mRNA; (2) MBH concentrations of tyrosine hydroxylase (TH, rate limiting enzyme in catecholamine biosynthesis) mRNA; (3) corresponding serum prolacin, corticosterone, luteinizing hormone (LH), and testosterone concentrations. POMC and TH mRNA levels were measured by RNase protection/solution hybridization assay; serum hormone levels were measured by radioimmunoassay. Adult male rats received subcutaneous injections of either nicotine or saline during the dark period of each day on an increasing frequency (1-3 injections/day) and dosage (0.4-0.5 mg nicotine/kg body weight) schedule over 4 weeks. The rats were sacrificed after 4 weeks treatment and at 1, 3, 7, 14 and 21 days withdrawal. Chronic daily nicotine administration induced significant changes in serum corticosterone, serum prolactin, MBH TH mRNA, and MBH POMC mRNA concentrations that tended to persist through day 3 of withdrawal; serum prolactin and MBH POMC mRNA concentrations were suppressed whereas serum corticosterone and MBH TH mRNA concentrations were stimulated. None of the parameters were significantly different from control levels following 7 or more days of withdrawal from nicotine, except for a significant decrease of MBH POMC mRNA concentrations on day 21. Chronic daily nicotine or withdrawal did not significantly alter serum LH or testosterone concentrations. These results suggest that chronic nicotine inhibited POMC gene expression and thus, probably, biosynthesis of beta-endorphin and other opiomelanocortins. We hypothesize that suppression of forebrain beta-endorphin synthesis in response to long-term nicotine exposure produces a chronically opioid deficient condition which may play an important role in maintaining nicotine self-administration and in mediating some changes during the nicotine withdrawal syndrome.     

Intraoperative injury to the spleen--organ preservation at any price?

This study evaluated serum nicotine and sensory differences of five different doses of nicotine polacrilex (0.0, 0.5, 1.0, 2.0 and 4.0 mg nicotine), three of which have been used as placebo doses in clinical trials (0.0, 0.5, and 1.0 mg) and two of which are currently available as pharmacologic treatments for smoking cessation (2.0 or 4.0 mg nicotine). Twenty-one smokers received, on different days and in random order, five pieces of each of the five doses of polacrilex. The objective of the study was to evaluate whether consistent serum nicotine and sensory differences would be observed between the doses. After 5 h use, the 0.0, 0.5, 1.0, 2.0, and 4.0 mg doses produced the following results: (1) there was a linear trend across the placebo doses of nicotine polacrilex in serum nicotine and nicotine flavor, although pairwise dose comparisons were not significant, (2) the 0.0 and 0.5 mg placebo doses resulted in serum nicotine and sensory ratings that were significantly different from the 2.0 mg dose, and even more so from the 4.0 mg dose, (3) the 1.0 mg dose was not different from the 2.0 mg dose on serum nicotine level and several sensory characteristics, though it was different from the 4.0 mg dose on both, and (4) the 4.0 mg dose resulted in significantly higher serum nicotine and usually higher sensory ratings than the 2.0 mg dose. Since the 0.0 mg placebo achieves sensory effects that are comparable to the nicotine-containing placebo doses, it is recommended over the 0.5 and 1.0 mg doses as the nicotine polacrilex placebo of choice in most clinical trials.     

Reduction in post-intubation respiratory resistance by isoflurane and albuterol

PURPOSE: This study examined the bronchodilating effects of 0.6 MAC and 1.1 MAC isoflurane (ISF) on respiratory system resistance (Rrs) following tracheal intubation and determined whether albuterol supplements that effect. METHODS: Sixty-seven adult patients were anaesthetized with 2 micrograms.kg-1 fentanyl and 5 mg.kg-1 thiopentone and their tracheas intubated following administration of 1 mg.kg-1 succinylcholine. Respiratory system resistance was measured following intubation and the patients then randomized to receive either 1.1 MAC ISF in oxygen or 0.6 MAC ISF in 50% nitrous oxide and oxygen. Ten minutes later, Rrs was again measured. Patients were then further randomized to receive albuterol or a placebo using incremental doses of 2, 5, and 10 puffs (albuterol puff = 90 micrograms) delivered via a metered dose inhaler at ten minute intervals. RESULTS: Isoflurane at 1.1 MAC decreased post-intubation Rrs by 23 +/- 5% (mean +/- sem) whereas the decrease was only 7 +/- 5% for 0.6 MAC ISF (P < 0.01). Two puffs of albuterol resulted in a further decrease of 12 +/- 3% (mean +/- sem) in Rrs compared with a 2 +/- 4% decrease in the placebo groups (P < 0.05). Additional puffs of albuterol resulted in no further changes in Rrs. CONCLUSION: We conclude that following tracheal intubation the reduction in Rrs produced by ISF is highly concentration dependent. Albuterol results in a small further reduction in Rrs.     

Isolation and Characterization of NP4, Arsenate-Reducing Sulfurospirillum, from Maine Groundwater

Parts of New England have naturally high arsenic concentrations in groundwater. High arsenic correlates broadly with bedrock type, but levels are patchy, so other conditions must affect arsenic mobilization. Microorganisms capable of arsenate (As(V)) respiration, if present, could affect arsenic speciation and mobility in groundwater. An arsenate-reducing bacterium, designated NP4, was isolated from groundwater obtained from a well in Northport, Me., with extremely high (>1,400?μg?L?1) arsenic. Sequencing of the 16S rDNA showed that NP4 groups with the Sulfurospirillum genus. It can grow using arsenate, nitrate, iron(III), selenate, manganese(IV), sulfite, sulfur or thiosulfate as terminal electron acceptors and lactate, formate and pyruvate as electron donors. It can also grow on fumarate or lactate alone. This Sulfurospirillum isolate is distinct from other members of the genus in its carbon and electron acceptor usage. The activity of this type of microorganism could negatively affect groundwater quality by converting As(V) to the more toxic and difficult to remove As(III) form.     

Facial EMG as an index of affective response to nicotine.

Negative affect reduction has been postulated to be a key feature of cigarette smoking. In the present study, facial electromyography (EMG), heart rate (HR), and skin conductance response (SCR) were used to evaluate the affective significance of acute nicotine administration and overnight withdrawal. Smokers (N = 115) attended four 90-min laboratory assessment sessions scheduled approximately 3 days apart. The sessions provided a complete crossing of 2 prelaboratory deprivation conditions (12-hr deprived vs. nondeprived) with 2 drug conditions (nicotine vs. placebo nasal spray). During each session, smokers viewed affective slides while facial EMG, HR, and SCR were recorded. Results indicated that for women, nicotine nasal spray resulted in lower corrugator EMG activity during both smoking-deprived and nondeprived sessions, compared with placebo. However, nondeprived women also showed an increase in zygomaticus EMG when given nicotine compared with placebo spray, whereas smoking-deprived women demonstrated a decrease in the zygomaticus response to nicotine compared with placebo. With men, nicotine also appeared to lower corrugator during deprivation, but not nondeprivation, compared with placebo spray, though the contrast only approached significance. With zygomaticus EMG, nicotine spray decreased men's zygomaticus responding during nondeprivation but not during deprivation, compared with placebo spray. The HR results reflected the stimulatory properties of the drug rather than nicotine's affective properties, whereas SCR was unresponsive to our experimental manipulations. The corrugator EMG results support negative reinforcement models of smoking that postulate that acute nicotine use reduces withdrawal-driven negative affect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

溶剂浮选-高效液相色谱法测定工业废水中酚类化合物

建立了溶剂浮选-高效液相色谱法测定工业废水中酚类化合物的新方法。采用溶剂浮选法分离富集水体中壬基酚（NP）、辛基酚（OP）和双酚A（BPA）,用高效液相色谱法测定各组分含量。对影响浮选效果的参数如浮选溶剂、试液pH值、氮气流速、浮选时间等因素进行优化,优选出最佳浮选条件。方法检出限分别为：0.03 μg/L（BPA）,0.25 μg/L(OP),0.21 μg/L(NP)。采用所述方法对石化地区的水样进行测定,样品加标回收率为83%～110%,RSD为4.2%～5.9%。