TC－A001型活性碳纤维降低卷烟中有毒物质的研究

本文报道采用ＴＣ－Ａ００１型活性碳纤维降低卷烟烟气中有毒物质的研究结果。活性碳纤维作为过滤材料对焦油、烟碱、放射性核素２１０钋和２１０铅，以及有毒有害的化学物质有明显的过滤作用。活性碳纤维和醋酸纤维复合滤嘴比醋酸纤维滤嘴和活性炭醋酸纤维复合嘴的过滤效果好。     

在纸烟滤嘴中用β-乳球蛋白阻留烟草中的3,4-苯并芘

1975年Ono等观察到牛奶的主要蛋白β-乳球蛋白(βLG)在水溶液中可以优先与苯并芘(Bap)和7,12-二甲基苯(a)蒽(实验动物的强致癌物)结合,而与非致癌的多环芳烃类似物Chrysene的亲合力很有限。因此,作者研究了含βLG的纸烟滤嘴对烟草烟中BaP的阻留作用。材料和方法:用市售的纸烟滤嘴作过滤物。按1957年Aschaffenburg等的方法制备βLG。把2或4 mgβLG分散注入滤嘴。测定滤嘴的压差。只用压差60±6 mm H_2O的滤嘴做实验。另取相当于6 mgβLG的包裹颗粒     

P－2复合材料烟滤嘴对纸烟苯并（α）芘量和焦油毒性的作用观察

观察和比较Ｐ－２复合材料与市售普通烟滤嘴、活性炭烟滤嘴的效率和作用特性。结果显示：苯并（α）芘含量的降低率，市售普通（三醋酸丝束）滤嘴为４０％，活性炭滤嘴为７７％，新研制的Ｐ－２复合材料则达８７％；ＣＳＣ小鼠急性毒性ＬＤ５０值依次为６０２、１８９６、２２９８ｍｇ／ｋｇ，ｐ－２复合材料可降低纸烟焦油毒性近４倍；吸烟者品尝试验表明Ｐ－２复合材料对烟味影响较小，和普通滤嘴相近。     

低焦油卷烟滤嘴通风孔的不同封堵程度对其主流烟雾成分的影响研究

目的研究低焦油卷烟上滤嘴通风孔不同封堵程度对其主流烟雾中一氧化碳(CO)、烟草特有亚硝胺(TSNAs)和多环芳烃(PAHs)成分释放量的影响,为正确认识抽吸低焦油卷烟的危害提供依据。方法选取国产某品牌4种低焦油含量卷烟(1、3、5和8 mg/支),以胶带缠绕方式将烟支滤嘴通风孔进行半堵和全堵,采用加拿大深度抽吸模式利用直线型吸烟机模拟吸烟过程,检测并比较滤嘴通风孔在被全堵、半堵和不堵时产生的主流烟雾中CO、烟草特有亚硝胺(NNN和NNK)和多环芳烃释放量的差异。结果国产某品牌低焦油标注量的卷烟在其滤嘴通风孔被全堵和半堵时,主流烟雾中CO、烟草特有亚硝胺和多环芳烃的释放量较不堵时有不同程度的升高。结论在实际抽吸过程中对卷烟通风孔的封堵习惯,有可能会增加烟草烟雾中有害物质的暴露,增加吸低焦油卷烟的健康风险。     

卷烟滤嘴中砷的高压消解-氢化物-原子荧光光度测定法

目的建立卷烟滤嘴中砷的高压消解-氢化物-原子荧光光度测定方法。方法卷烟滤嘴经高压消解及优化实验条件后,用原子荧光光度法测定其中的砷含量。结果实验表明,方法在0～20μg/L浓度范围内线性相关系数为0.9997,检出限为0.021 1μg/L,加标回收率在86.6%～103.4%之间,方法精密度(RSD)小于5%。结论该法具有简便、灵敏、准确等特点,适合于卷烟滤嘴中砷含量的测定。     

北京市四区县中学校外售烟现状

了解北京市中学校外售烟现状,为政府制定校园周边控烟政策提供依据.方法 采用PPS抽样方法,对北京市城郊4个区县中学校门外100 m范围内的卷烟零售点进行调查.结果 共调查学校87所,58所(66.7%)校门外100 m范围内存在卷烟零售点,经x2检验,不同县区、不同类别学校校门外售烟点比例差异均无统计学意义(P值均>0.05).128家烟草零售点中104家(81.3%)有向学生售烟的行为,48.4%未悬挂烟草专卖零售许可证,61.7%未张贴“禁止向未成年人售烟”标识.向学生售烟和未悬挂“烟草专卖零售许可证”比例在不同区县、学校类型、卷烟零售点类型上差异均有统计学意义(P值均<0.05);未张贴标识比例在不同区县和不同卷烟零售点类型上差异均有统计学意义(P值均<0.05).87家(68.0%)卷烟零售店店主不了解学校门外100 m范围内禁止售烟的规定.结论 北京市中学校外卷烟零售点向中学生售烟现象严重,与法律法规中的相关要求不符.     

活性炭复合滤嘴对香烟烟气中自由基含量的影响

目的 研究活性炭复合滤嘴对香烟烟气中自由基含量的影响.方法 用电子自旋顺磁共振(ESR)法对9种使用活性炭复合滤嘴的国内外香烟样品中粒相及气相自由基进行检测.结果 实验样品中进口香烟A1气相自由基降低最多,达到53.8%;粒相自由基降低最多的是国产香烟A1,达到31.3%.进口香烟B2气相自由基增加最多,达到78.6%,粒相自由基含量增加最多的是进口香烟A2,达到47.7%.气相自由基及粒相自由基含量降低与增加的样品数量基本接近,同一品牌、不同型号的香烟,活性炭复合滤嘴的作用也表现出差异.3个没有使用抗自由基物质的香烟样品也具有与使用该物质的香烟样品相近的降低自由基的效果.结论 使用活性炭复合滤嘴不一定能够降低香烟烟气中的自由基含量,活性炭对气相自由基含量的影响明显大于对粒相自由基含量的影响.     

不同烟具过滤后的烟草凝聚物致突变性比较

对国内民间传统烟具进行了卫生毒理学评价。3种烟具和过滤嘴均能不同程度地降低香烟和烟丝主流烟中凝聚物含量、有机提取物含量和致突变性。其效果以竹水烟筒最佳,其余烟具依次为铜水烟壶>旱烟具>过滤嘴。     

电子烟气溶胶提取物细胞增殖毒性研究

目的探讨电子烟气溶胶提取物的体外急性毒性,为电子烟的评价提供依据。方法电子烟经吸烟机器人抽吸,产生的烟气气溶胶经A(含分子筛滤嘴)、B(不含分子筛滤嘴)不同传输装置后经剑桥滤片捕获,将MEM、DMSO提取剑桥滤片吸附的烟气气溶胶后所得的水、脂溶性气溶胶提取液及烟油原液分别与中国仓鼠卵巢细胞(CHO-K1)、人支气管上皮样细胞(HBE)、人胚肺成纤维细胞(MRC-5)三株细胞共孵育24 h,以CCK-8检测细胞活性。结果烟油原液对各细胞增殖抑制呈浓度依赖性升高趋势,烟油浓度在21.620～108.1 mg/ml时对MRC-5和CHO-K1产生细胞增殖毒性,差异有统计学意义(P0.05),烟油浓度在10.810～108.1 mg/ml时对HBE产生细胞增殖毒性,差异有统计学意义(P0.05);各细胞的半数抑制浓度(IC_(50))依次为39.35 mg/ml(MRC-5)42.69 mg/ml(CHO-K1)55.91 mg/ml(HBE)。B传输装置水溶性提取剂1.31 mg/ml(用烟油浓度标定)时具有抑制作用,差异有统计学意义(P0.05);在检测浓度范围内,各细胞的IC_(50)依次为1.24 mg/ml(CHO-K1)1.91 mg/ml(MRC-5)2.08 mg/ml(HBE);IC_(50)比烟油原液低一个数量级,差异有统计学意义(P0.05)。A传输装置的水、脂提取物及B传输装置的脂提取物对细胞增殖无抑制作用。结论烟油原液可抑制细胞增殖,加热后产物(即电子烟气溶胶提取物)的细胞增殖抑制能力与传输装置的构造有关,含滤嘴的A装置产生的电子烟气溶胶未见细胞增殖毒性,普通滤嘴B装置的水溶性提取物表现出细胞增殖毒性,且比烟油原液高。3种细胞中,CHO-K1对电子烟气溶胶的毒性最敏感,MRC-5对烟油的毒性最敏感。     

番茄红素对苯并(a)芘诱发小鼠前胃组织癌变的影响

目的观察番茄红素对苯并(a)芘[B(a)P]诱发小鼠前胃组织癌变过程的影响及其可能的作用机制。方法昆明小鼠随机分成5组(n=30):正常对照组、B(a)P组、番茄红素高[20mg/kg+B(a)P]、中[10mg/kg+B(a)P]、低[5mg/kg+B(a)P]3个不同剂量的实验组,实验组与B(a)P组给予B(a)P,建立前胃癌模型,观察不同浓度的番茄红素对小鼠前胃癌形成的作用;同时用单细胞凝胶电泳法检测外周血淋巴细胞DNA损伤情况,检测超氧化物岐化酶(SOD)、丙二醛(MDA)及谷胱甘肽过氧化物酶(GSH-Px)的含量。结果正常对照组未见肿瘤形成,其余4组均见肿瘤形成,并经病理证实。番茄红素高、中、低剂量组、B(a)P对照组前胃肿瘤发生率分别为50%、60%、80%、100%。与正常对照组相比,番茄红素高、中、低剂量组和B(a)P对照组MDA含量升高,SOD活性下降,DNA氧化损伤加重,差异有显著性(P<0.05)。与B(a)P对照组相比,番茄红素高剂量组MDA含量降低,高、中剂量组SOD活性升高,DNA氧化损伤减轻,差异有显著性(P<0.05)。番茄红素对GSH-Px影响不显著。结论番茄红素具有抑制肿瘤...     

Nicotine dependence, quit attempts, and quitting among smokers in a regional population sample from a country with a high prevalence of tobacco smoking

BACKGROUND: Nicotine dependence might function as a barrier to smoking cessation. Therefore, the goal was to determine whether single symptoms of nicotine dependence are related to the number of quit attempts and smoking status. METHODS: In a random population sample of 4075 women and men aged 18-64, drawn from 47 German communities, data about nicotine dependence according to the US Diagnostic and Statistical Manual of Mental Disorders and according to the Fagerstr?m Test for Nicotine Dependence (FTND), and data on quit attempts and quitting were collected at baseline with an interview and 30 months later with a questionnaire. RESULTS: Nicotine dependence, in particular withdrawal, was related to a high number of quit attempts and to remaining a current smoker. The urgent need for tobacco, craving for nicotine, smoking to avoid withdrawal, and the expectation of increased appetite or weight gain correctly classified smoking status in 72.1% of individuals through logistic regression analysis. CONCLUSIONS: Nicotine dependence is a strong factor that may partly explain the failure of a subpopulation of smokers to live abstinent. Population-based interventions should include measures of tobacco control and brief interventions carried out, for example, by experts in health care.     

Nicotine and carbon monoxide: effects on the isolated rat heart

We studied the combined effects of carbon monoxide (CO) and nicotine on the performance of the isolated rat heart. Hearts were removed from laboratory rats and perfused through the aorta with 95% O2-5% CO2 (oxygenated) Krebs-Henseleit solution (KHs). After 30 min, the perfusate was switched rapidly to one of three solutions: KHs containing 10% CO-85% O2-5% CO2 (CO), 10 micrograms/ml nicotine (Nic), or CO combined with nicotine (CO + Nic). KHs containing CO increased coronary flow by 41% without affecting heart rate or pulse pressure. Coronary flow returned to control values during recovery in oxygenated KHs. KHs containing Nic decreased heart rate by 20% and coronary flow by 28%. Pulse pressure was unaffected. Both heart rate and coronary flow returned towards control values during recovery in oxygenated KHs. KHs containing CO + Nic decreased heart rate 16% but stimulated coronary flow 13%. Heart rate returned towards control values during recovery; however, coronary flow, which declined to control values after 8 min, continued to decrease during recovery. These results indicate that the separate effects of CO and Nic on coronary flow in the isolated rat heart are opposing and reversible, but that the decrease they produce in combination is irreversible.     

Smoking in Colombian medical schools: the hidden curriculum

BACKGROUND: Tobacco companies are focusing their interest in less developed countries. In the absence of governmental opposition, physicians are expected to lead tobacco control efforts. We studied Colombian medical students' smoking prevalence and tobacco attitudes. METHODS: First- and fifth-year students from 11 medical schools in seven Colombian cities answered anonymous, self-administered, 38-item questionnaires. Additionally, smokers answered the Fagerstr?m Test for Nicotine Dependence (FTND). RESULTS: Two thousand twenty-one students (males 50.6%; age 15-44, median 19) completed the survey; average response rate was 89.9%. Globally 25.9% of students were current smokers (males 27.9%, females 24.0%). Living at higher altitude and attending private universities were associated with higher prevalence (P < 0.001). Males had a higher chance of having given up smoking (P < 0.05); 91.3% of current smokers would like to quit; 67.3% of all smokers and 44.8% of daily smokers scored 0 in the FTND. Prevalence was similar among first- and fifth-years, but fifth-year students were more complacent with smoking in health centers and showed a lesser desire to quit. CONCLUSIONS: Medical students' smoking prevalence is similar to that of the general population. Tobacco control strategies need to be included in the curriculum. Nicotine addiction does not seem to be the main perpetuating factor.     

Dietary fiber reduces the antioxidative effect of a carotenoid and α-tocopherol mixture on LDL oxidation ex vivo in humans

BACKGROUND: Antioxidant concentrations in low density lipoproteins (LDL) are an important determinant for their susceptibility to oxidation and can be modulated by dietary intake. AIM OF THE STUDY: In the present study, the influence of dietary fiber on the antioxidant enrichment and the oxidation resistance of LDL after antioxidant supplementation is investigated. METHOD: An antioxidant supplement consisting of beta-carotene, lycopene, lutein, canthaxanthin and alpha-tocopherol was given to six young women together with a standard meal. Using a cross-over study design, each subject received the standard meal without additional dietary fiber and enriched with pectin, guar, or cellulose in a random order. To determine the resistance of LDL against copper ion-induced oxidation, the formation of conjugated dienes was measured. RESULTS: Eight, 10, and 24 hours after antioxidant supplementation the isolated LDL revealed significantly (p < 0.05) increased antioxidant concentrations; addition of pectin, guar, or cellulose to the meal depressed this increase. Concomitantly, the observed increase in the resistance of LDL against oxidation (measured as lag phase) was lower with dietary fiber supplementation than that found without. On average, pectin, guar, and cellulose reduced the increase of the lag phase (measured without addition of dietary fiber) by 38%, 22%, and 18%, respectively. CONCLUSIONS: These results indicate that dietary fiber supplementation decreases the antioxidative effect of a supplement consisting of carotenoids and alpha-tocopherol in LDL, an effect that is likely to be mediated by a reduced bioavailability of these antioxidants in the gut.     

Effects of tomato pomace and mixed-vegetable pomace on serum and liver cholesterol in rats

The effects of tomato pomace and mixed-vegetable pomace, vegetable processing by-products, on serum and liver cholesterol were compared against pectin, wheat bran, cellulose, and lignin. Male Sprague-Dawley rats (100 g) were fed high sucrose, semi-purified diets containing basal (0), 5% or 10% of the fiber source and either 0, 0.5% cholesterol or 0.5% cholesterol + 0.125% sodium cholate. After 28 days, there were highly significant differences (P less than 0.001) in serum and liver cholesterols due to fiber source, dietary cholesterol and the interaction. The effect of fiber source level was significant (P less than 0.05) for liver cholesterol only. Pectin groups had serum and liver cholesterol levels lower (P less than 0.05) than the others. At the 10% level, tomato pomace, wheat bran and lignin (Indulin AT) groups had serum cholesterols higher (P less than 0.05) than basal; the mixed-vegetable pomace and cellulose groups were not different from basal. Liver cholesterols of tomato pomace, mixed-vegetable pomace, wheat bran and lignin groups were not different at the 10% level, but were higher than the pectin, cellulose and basal groups (P less than 0.05). In a second experiment, serum cholesterols of rats fed pectin were lower (P less than 0.05) than for those fed cellulose or two types of lignin (Indulin AT, Reax 27).     

Effect of dietary fiber in insulin-dependent diabetics: insulin requirements and serum lipids

Four young adult (18 to 26 years old), nonobese human subjects (two men and two women) with insulin-dependent diabetes mellitus volunteered to consume a series of three diets: baseline (normal daily intake), wheat bran (normal daily intake + 78 gm wheat bran per day), and cellulose (normal daily intake + 30 gm cellulose per day). Wheat bran and cellulose diets both contained 60 gm dietary fiber, with 50% of the dietary fiber from wheat bran or cellulose, respectively. Each patient served as his or her own control. Randomized diets were of 6 weeks' duration, separated by a 4-week "recovery" period. At the conclusion of each diet, subjects were hospitalized and underwent 12 hours of computer-controlled, insulin-glucose infusions. Significant decreases were seen in fasting cholesterol (p less than .05), but the decreases seemed to result largely from the significant reductions in high-density lipoprotein cholesterol. A large reduction in triglycerides was noted with cellulose feeding but not with wheat bran. The mean daily insulin dose decreased (p less than .05) in response to fiber addition (8% and 10% decrease for wheat bran and cellulose feeding, respectively). Mean biostator insulin requirements decreased 11% with wheat bran (p less than .05) but not with cellulose. During biostator monitoring, subjects experienced delayed postprandial blood glucose and insulin-infusion rate peaks with both wheat bran and cellulose feeding. The wheat bran diet reduced peak blood glucose concentration and peak insulin infusion rate in comparison with baseline and cellulose diets. The data suggest that high levels of cellulose or wheat bran are of marginal benefit to insulin-dependent diabetic subjects.     

The hypocholesterolemic effect of lemon peels,lemon pectin,and the waste stream material of lemon peels in hybrid F<Subscript>1</Subscript>B hamsters

Summary Background We found in preliminary studies with hamsters that citrus peels have a cholesterol lowering effect comparable to that of pectin extracted from these peels. Aim of the study We wanted to examine whether the cholesterol lowering effect of the peels could be completely accounted for by the pectin in the peels. Methods We fed cholesterol enriched (0.1 %,w/w) semipurified diets containing 3 % (w/w) of cellulose, lemon peels, lemon pectin, and the waste stream material of the lemon peels to hybrid F₁B hamsters for a period of 8 weeks. The waste stream of the lemon peels is the left over after extraction of the lemon pectin. Results Feeding the semipurified diets resulted in an increase of plasma cholesterol levels in all the dietary groups after 2 and 4 weeks on the diets. Cholesterol concentrations in the cellulose fed hamsters continued to increase after 4 weeks on the diet, whereas cholesterol levels in the other groups had reached a plateau. As a consequence, the plasma cholesterol levels in the hamsters fed the peels (5.59 ± 0.74 mmol/L, mean ± SD, n = 14), pectin (5.19 ± 0.48 mmol/L), or waste stream (5.53 ± 0.94 mmol/L) were lower than those in the hamsters fed cellulose (6.71 ± 1.52 mmol/L) after 8 weeks on the diets. Differences in total plasma cholesterol were reflected in differences in both VLDL and LDL cholesterol concentration, but this effect was more distinct for the VLDL. There was no effect of the type of fiber on HDL cholesterol levels. Liver cholesterol concentrations paralleled the concentrations of plasma cholesterol and the liver cholesterol concentrations in the hamsters fed the peels (3.57 ± 1.01 μmol/g liver, mean ± SD, n = 14), pectin (4.86 ± 1.42), and the waste stream (4.96 ± 1.89) were lower than those in the cellulose group (7.19 ± 2.32). The hamsters fed the peels, pectin, or waste stream tended to have a higher excretion of fecal bile acids and neutral sterols then the cellulose fed hamsters. Conclusion The results of this study suggest that lemon peels and the waste stream of the lemon peels are as effective in lowering plasma and liver cholesterol in hamsters as the pectin extracted from the peels and that also compounds other than pectin are probably responsible for the cholesterol lowering effect of the citrus peels. Received: 20 September 2001, Accepted: 17 December 2001     

Improved smoking cessation in smokers given ultrasound photographs of their own atherosclerotic plaques

BACKGROUND: We examined whether making smokers aware that they had developed peripheral atherosclerosis would improve smoking cessation. METHODS: Smokers selected from the general population were randomly allocated to undergo high-resolution B-mode ultrasonography of their carotid and femoral arteries. All smokers received quit-smoking counseling. Smokers with > or =1 atherosclerotic plaque were given two photographs of a plaque with a relevant explanation. Quit rates were assessed by telephone 6 months later. RESULTS: Seventy-nine smokers did not undergo ultrasonography (A). Among the 74 smokers submitted to ultrasonography, 20 had no plaque (B) and 54 had > or =1 plaque (C). Quit rates were, respectively, 6.3, 5.0, and 22.2% in groups A, B, and C. Quit rates were higher in smokers submitted to ultrasonography (B + C vs A; P = 0.031) and in those receiving photographs (C vs A + B; P = 0.003). Smoking cessation was independently associated with intervention C (OR = 6.2; 95% CI = 1.8-21) and a white-collar job but not with age or gender. CONCLUSIONS: Providing smokers with photographs demonstrating atherosclerosis on their own person was an effective adjunct to physician's advice to quit smoking. Since ultrasonography is used increasingly often in clinical practice for cardiovascular risk stratification, this can provide an additional opportunity and means to deter smokers from smoking.     

Influence of fiber fermentability on nutrient digestion in the dog

Eight mature dogs (17.2 +/- 0.2 kg) surgically fitted with ileal T-cannulas were used in a replicated 4-x-4 Latin-square-design experiment to evaluate nutrient disappearance at the terminal ileum and through the digestive tract. Two fiber types, cellulose, a crystalline, slowly fermented fiber, and pectin, a soluble, rapidly fermented fiber, were fed in different increments, and the effects on nutrient availability were assessed. Treatments included 1) 100% cellulose, 2) 66% cellulose and 33% pectin, 3) 66% pectin and 33% cellulose, and 4) 100% pectin. Fiber was added at 10% of diet dry matter (DM). Diets were fed at 100% of ME for maintenance and offered at 0730 and 1730 h. All periods were 21 d, which included 3 d of diet transition and 7 d of adaptation. Daily DM intake was 210 +/- 5 g. Total tract and large-intestine DM digestibility increased linearly (P < 0.01) with increased pectin. These changes in DM digestion were largely the result of changes in fiber digestion. Fermentation of total dietary fiber in the large intestine went from less than zero to 39% of ileal flow (linear, P < 0.01). Total-tract crude-protein digestibility decreased linearly (P < 0.01) with increased pectin. This study demonstrated that fiber fermentability significantly affects digestion in the dog. Increasing fermentable fiber increased the digestion of DM and energy. However, increased fiber fermentability inversely affects crude protein digestibility. The lower crude-protein digestibility could be attributed to larger microbial protein excretion as a result of greater fermentation of pectin versus cellulose.     

Quit attempts among African American teenage smokers seeking treatment: gender differences

BACKGROUND: African Americans experience disproportionate smoking-related mortality. Because established smoking during youth predisposes to adult smoking and serious health consequences, characterizing ethnic differences in adolescent smokers' self-quit attempts may inform ethnic-specific approaches to youth smoking cessation. METHODS: African American and European American teenage smokers applying to a teenage smoking cessation study (2000-2003) provided smoking-related data, including characteristics of previous cessation attempts and prior use of nicotine replacement therapy (NRT). Tobacco dependence was assessed using the Fagerstrom Test of Nicotine Dependence (FTND). RESULTS: Of 980 (15.5 +/- 1.3 years, 41.8% African American, 59.9% female) participants, African Americans boys were significantly less likely than European American boys to report a prior quit attempt (OR = 0.35, 95% CI 0.17-0.73, P = 0.0049) or to have used NRT (OR = 0.60, 95% CI 0.36-0.998, P = 0.049) after adjusting for years smoked and FTND score. African American girls were more likely to report a prior request for cessation treatment than European American girls after adjusting for FTND and years smoked (OR = 2.19, 95% CI 1.37-3.48, P = 0.001). CONCLUSIONS: While increasing education and outreach to African American boys and enhancing access to formal cessation programs for African American girls who smoke may be beneficial, our findings warrant extension to non-treatment-seeking teenage smokers.