Inhibitory effect of sowthistle (Ixeris dentata) on development and expression of behavioral locomotor sensitization to nicotine in rats

The aim of this study was to investigate the effects of sowthistle (Ixeris dentata, IXD) on development and expression of nicotine-induced locomotor sensitization and underlying neuronal activation reflected by c-Fos expression in rats. Rats were pretreated with IXD 30 min before a daily injection of nicotine during an 8-day development phase and then challenged with nicotine after a 6-day withdrawal period. In another set of experiments, same IXD doses were administered once 30 min before nicotine challenge. Daily IXD treatment during development phase was not effective in blocking nicotine-induced locomotor sensitization in rats. However, a single IXD treatment after the development and withdrawal periods of nicotine sensitization significantly alleviated sensitized locomotor behavior on day 15. These behavioral results were coincident with significant inhibition of nicotineinduced c-Fos expression in the nucleus accumbens. These results indicated that IXD pretreatment significantly blocked the expression, but not the development of nicotine-induced locomotor sensitization in rats.     

The neurobiology of tobacco dependence: a preclinical perspective on the role of the dopamine projections to the nucleus accumbens [corrected]

It is now widely accepted that nicotine is the primary addictive component of tobacco smoke and that a majority of habitual smokers find it difficult to quit smoking because of their dependence upon this component of the smoke. However, although nicotine replacement therapy elicits a clinically valuable and significant improvement in the number of quit attempts that are ultimately successful, its efficacy remains disappointingly low. This review considers some of the reasons for this problem. It focuses on the hypothesis that stimulation of the dopamine (DA) projections to the medial shell and the core of the nucleus accumbens play complementary roles in the development of nicotine dependence. The hypothesis proposes that increased extra-synaptic DA in the medial shell of the accumbens confers hedonic properties on behaviors, such as smoking, which deliver nicotine, and thereby increase the probability that the response is learned. It also summarizes the evidence that the primary role of the increased DA overflow, observed in the accumbal core of nicotine-pretreated individuals, challenged with nicotine, is the attribution of incentive salience to cues associated with delivery of the drug and the transition to Pavlovian responding to these conditioned stimuli. The review argues that sensitization of the DA projections to the accumbal core, and the behaviors that depend upon this process, play a pivotal role in the maintenance of the tobacco smoking habit and that it is this component of the dependence that is inadequately addressed by nicotine replacement therapy.     

L-arginine prevents impaired endothelium-dependent cerebral arteriolar dilatation during acute infusion of nicotine.

Exogenous treatment with L-arginine has been shown to restore impaired nitric oxide synthase (NOS)-dependent dilatation of peripheral blood vessels during disease states. We have shown that nicotine impairs NOS-dependent arteriolar dilatation in the cerebral circulation. However, the role of L-arginine in impaired responses of cerebral arterioles during infusion of nicotine has not been examined. Thus the goal of the present study was to examine the role of L-arginine in nicotine-induced impairment of cerebral arteriolar reactivity. We measured the diameter of pial arterioles in response to NOS-dependent (5'-adenosine diphosphate [ADP] and acetylcholine) and NOS-independent (nitroglycerin) agonists before and after infusion of vehicle or nicotine (2 microg/kg/min intravenously for 30 min followed by a maintenance dose of 0.35 microg/kg/min) in the absence or presence of L-arginine (10(-3) M). We found that topical application of L-arginine to cerebral microvessels during infusion of nicotine could prevent impaired NOS-dependent vasodilatation. We suggest that exogenous L-arginine may have a beneficial role in preventing cerebral microvascular dysfunction during exposure to nicotine.     

Dietary spices protect against hydrogen peroxide-induced DNA damage and inhibit nicotine-induced cancer cell migration

Spices are rich sources of antioxidants due to the presence of phenols and flavonoids. In this study, the DNA protecting activity and inhibition of nicotine-induced cancer cell migration of 9 spices were analysed. Murine fibroblasts (3T3-L1) and human breast cancer (MCF-7) cells were pre-treated with spice extracts and then exposed to H₂O₂ and nicotine. The comet assay was used to analyse the DNA damage. Among the 9 spices, ginger, at 50 μg/ml protected against 68% of DNA damage in 3T3-L1 cells. Caraway, cumin and fennel showed statistically significant (p < 0.05) DNA protecting activity. Treatment of MCF-7 cells with nicotine induced cell migration, whereas pre-treatment with spices reduced this migration. Pepper, long pepper and ginger exhibited a high rate of inhibition of cell migration. The results of this study prove that spices protect DNA and inhibit cancer cell migration.     

Location and nature of the epidermal permeability barrier

The lowest region of human and pig stratum corneum has been isolated as an integral layer, referred to as the stratum compactum. This preparation is resistant to disruption by enzymes, 6M urea, Triton X-100 and organic solvents. Our evidence suggests that penetration of materials to and through the corneum depend on the state of cohesion between cells, and of the organization of intercellular lipid species. As the cells move up towards the outside of the stratum corneum, the cohesive forces are reduced due to desmosome degradation and lipid modifications, with ultimate dyshesion and sloughing of individual cells.
A number of linoleate-rich lipids have been identified within human and pig epidermis which could contribute to the formation or maintenance of an epidermal permeability barrier. Our current belief is that the molecule key to barrier function is a hydroxylated linoleate derivative which appears to be formed in the stratum compactum region.
Situation et nature de la barrière de perméabilitéépidermique     

Prediction and measurement of surfactant action upon human skin under realistic conditions

The lysosomal enzyme acid phosphatase has been characterized and quantified in tapestrip biopsies of human stratum corneum by means of a sensitive spectrofluorometric procedure. When the stratum corneum of panellists was exposed to dilute solutions of various surfactants under realistic exposure conditions, the changes observed in stratum corneum acid phosphatase specific activity have been found to correlate very closely with the visual, macroscopic changes such as dryness and flakiness, that are elicited in skin as a result of surfactants. This method monitors denaturation of stratum corneum proteins, which is an important feature of skin surfactant interactions, and serves as an effective, non-invasive predictive tool for skin irritancy and mildness of surfactants.
Prevention et mesure de l'action des tensio-actifs sur la peau humaine dans des conditions conformes a la réalité     

Nicotine dependence symptoms among adolescents with psychiatric disorders: using a Rasch model to evaluate symptom expression across time.

Little is known about the longitudinal course of symptoms of nicotine dependence among adolescents following interventions designed to affect smoking behavior, particularly among high-risk samples. We used an item-response modeling strategy to examine how well nicotine dependence symptoms cohere to a latent construct, the stability of the construct over time, and the sensitivity of the nicotine dependence symptoms to changes in smoking patterns among adolescents with comorbid psychopathology. Assessments occurred prior to cessation treatment delivered within a randomized clinical trial and again at 6 and 12 months after treatment. We used a Rasch item-response modeling approach to examine nicotine dependence as measured by a structured Adolescent Nicotine Dependence Interview (ANDI) and by the Modified Fagerstr?m Tolerance Questionnaire (mFTQ). These analyses provided support for a unidimensional latent measurement model that can be used to organize symptoms of nicotine dependence obtained from ANDI and mFTQ measures. The derived measure showed good construct validity with significant relationships to smoking levels and salivary cotinine levels. The typical symptom patterns and the relative severity of nicotine dependence symptoms remained stable over multiple assessments. Changes in smoking levels were related longitudinally to changes in nicotine dependence, and changes in nicotine dependence were related to changes in motivation to quit and readiness to change smoking behavior. Several behavioral symptoms were sensitive to change in smoking rate over time, whereas core symptoms of physiological dependence did not evidence significant changes. Results suggest that DSM-IV and mFTQ measures of nicotine dependence provide complementary information when assessing nicotine dependence levels among adolescents with psychiatric disorders.     

A new technique for the evaluation of cosmetics effect on mechanical properties of stratum corneum and epidermis in vitro

The mechanical properties of stratum corneum and epidermis have been measured in vitro and a dispersity of approximately 30% to 50% between samples from the same donor has been found. To overcome such a limitation, a technique was developed in order to compare the mechanical properties of the same skin sample before and after treatment. The chosen parameter (initial slope of the stress-strain curve) appeared to be influenced by the topical application of products. A different time response was found with stratum corneum and epidermis reflecting their structural differences.
Une nouvelle technique d'evaluation de l'effet des produits cosmétique sur les propriétés mécaniques du stratum corneum et de l'épiderme humains (etude in vitro )     

不同形态烟碱在电子烟气溶胶中的释放研究

  目的  研究游离烟碱、吸附烟碱、包合烟碱、不同比例烟碱和酒石酸调配物在电子烟气溶胶中释放规律。  方法  测定含有不同形态烟碱的电子烟烟液中烟碱含量及pH值变化,比较不同形态烟碱在电子烟气溶胶中释放情况及感官质量评价差异。  结果  相对于含游离烟碱的电子烟烟液对照,（1）添加环糊精修饰氧化石墨烯、氧化碳纳米管、羧甲基纤维素、羟丙基环糊精和酒石酸的处理,可测定烟碱浓度均有降低,酒石酸处理pH值降低,其余不变;（2）添加氧化碳纳米管的处理,气溶胶中烟碱释放稳定性降低;添加环糊精修饰氧化石墨烯、羟丙基环糊精、羧甲基纤维素和酒石酸的处理,烟碱释放稳定性较好;（3）添加羟丙基环糊精的处理,喉部冲击感降低,添加酒石酸的处理,烟碱气息较弱,喉部劲头和刺激明显降低。  结论  在含有游离烟碱的电子烟烟液中添加适量的羟丙基环糊精、羧甲基纤维素和酒石酸可以有效增加烟气气溶胶中烟碱释放的稳定性、提升电子烟的感官质量。      

Effect of Blending on the Composition and Acceptability of Blends of Unripe Banana and Pigeon Pea Flours

Proximate composition, amino acid profile, trace minerals, functional properties and organoleptic evaluation of blends of unripe banana and pigeon pea flours were studied. The proximate composition of the blends showed that addition of pigeon pea significantly (p < 0.05) increased the protein from 2.40 – 14.48 ± ^0.11. Similarly, the ash, fat and crude fibre increased while carbohydrate content significantly decreased from 79.86 – 55.00 ± ^0.47. The amino acid profile showed that addition of pigeon pea up to 37.5% levels resulted in increase in all amino acids evaluated. The blend amino acid status was adequate for adult nutrition when compared to the FAO recommendations. However the blend was found deficient in lysine, leucine, iso-leucine and phenylalanine when compared with the FAO recommendations for infants. Increased levels of pigeon pea in the blend also resulted in significant increases in potassium, phosphorus, sodium, magnesium and calcium. Similarly, increased levels of pigeon pea in the blend significantly increased the gelation concentration and foaming capacities while the bulk density, water absorption and oil absorption capacities significantly (p > 0.05) decreased. The results showed that blending of pigeon pea with unripe plantain would produce meals of balanced nutrient densities for adults.     

Optimization of process parameters for the development of a cheese analogue from pigeon pea (Cajanus cajan) and soy milk using response surface methodology

Response surface methodology was used to optimize starter culture concentration (3–7%), pigeon pea–soy solids ratio (1 : 0.3–1 : 1.1), pigeon pea–water ratio (1 : 12–1 : 9), incubation temperature (37–45C) and coagulation temperature (75–95C) in the development of a cheese analogue from pigeon pea and soy milk. Pigeon pea milk and soy milk were prepared by a hot water grinding method, followed by filtration and inoculation. Cheese analogue was obtained through coagulation of the fermented milk by boiling for 15 min, followed by filtration using double-layered muslin cloth and pressing at 1 kg/cm ² pressure for 1 h. The results showed that the total solids recovery (TSR), protein content, fat content and pH varied from 51.09–62.61%, 40.04–55.93%, 9.35–15.36% and 4.48–4.9, respectively, depending on the experimental conditions. The optimum conditions of process parameters for maximum total solids recovery were 6.0% starter culture concentration, 1 : 0.4 pigeon pea–soy solids ratio, 1 : 11 pigeon pea–water ratio, 40.5C incubation temperature and 88.5C coagulation temperature.     

Melanin and nicotine: A review of the literature.

The role of melanin in nicotine uptake and metabolism has received little attention. Because nicotine has been shown to accumulate in tissues containing melanin, exploring links between melanin and nicotine may provide additional clues to understanding smoking behavior and disease effects. To examine the scientific literature on the relationship between melanin and nicotine, we conducted a PubMed search. We also searched online archives of internal tobacco industry documents. We retrieved and reviewed 82 published research papers related to melanin and nicotine or melanin and metabolism of other drugs, and 150 relevant internal tobacco industry documents. The published literature suggests that nicotine may accumulate in human tissues containing melanin and this retention may increase melanin synthesis. Existing research on the relationship between melanin and nicotine lacks an adequate consideration of this relationship's potential impact, if any, on nicotine metabolism, level of nicotine dependence, and ability to quit smoking. Differential accumulation of nicotine in melanin-containing tissues could have implications for individuals with high levels of melanin.     

The nicotine market: an attempt to estimate the nicotine intake from various sources and the total nicotine consumption in some countries.

Tobacco--particularly smoked products--has been associated with great harm and growing public disapproval and can be expected to suffer in the marketplace. This situation has created opportunities for other less harmful nicotine-containing products such as smokeless tobacco and nicotine replacement products, which are gaining public support. Little is known about the level of nicotine intake in our society. Tobacco sales are known, but how much nicotine is extracted and actually absorbed by users is largely unknown. The present study is a first attempt to estimate uptake of nicotine from tobacco and nicotine replacement products and to map nicotine consumption in a few countries, with special emphasis on Sweden. Relevant pharmacokinetic studies for three types of nicotine-containing products (cigarettes, smokeless tobacco, and nicotine replacement products) were analyzed for bioavailable nicotine. Estimates of nicotine intake from each category were made. These were then multiplied by the amount consumed in the respective countries. Tobacco consumption statistics were usually from official records of taxed sales. In Sweden about 54% of all nicotine intake comes from smoked sources, 45% from nonsmoked tobacco, and 1.3% from nicotine replacement products. For men, 63% of the nicotine consumed comes from nonsmoked tobacco. Per-capita nicotine intake per year for adults aged 15 years or older is 3,321 mg for Austria, 3,043 mg for Sweden, 3,014 mg for Denmark, 2,955 mg for the United States, 2,244 mg for Norway, and 2,023 mg for Finland. Compared with cigarette smokers, snus users seem to have a somewhat higher daily intake (34 mg vs. 25 mg). The cleanest nicotine products, nicotine replacement products, represent a negligible part (about 1%) of the total nicotine consumption in most countries.     

Effect of microwave treatment on the cooking and macronutrient qualities of pulses

The effect of microwave treatment to reduce the cooking times of five pulses, namely red lentil, chickpea, pigeon pea, mung bean, and pinto bean, were determined in this study. Pulses from 10 to 18% moisture contents were treated using 400 to 600 W microwaves for 14 to 56 s. The cooking times of microwave-treated pulses were significantly lower than that of the control samples. The lowest cooking time was observed for 18% moisture content chickpea and pigeon pea treated with 600 W for 56 s. The Fourier transform mid-infrared spectra in both lipids and fingerprint regions showed the macronutrients differences among the five pulses. Major changes were observed in the amide I region of microwave treated pulses. This effect of microwave treatment was higher in red lentil, chickpea, and mung bean than in pigeon pea and pinto bean at 10% moisture content. At 18% moisture content, the change of β-sheets to aggregates was observed in all pulses due to microwave treatment.     

烤烟烟碱累积特点研究

田间状况下对烤烟烟碱的累积特点研究表明,烟碱的累积与烤烟对氮素的吸收并不同步,氮的吸收强度在移栽后2个月左右达到最高峰,而此时,烟碱的累积才开始急剧增加,时间刚好发生在打顶之后,烟碱的最大累积强度发生在移栽后3个月左右。不同器官中,打顶前烟根烟碱含量高于烟叶,而打顶后烟叶远高于根系,烟茎中烟碱含量最低。单位重量的根系所合成的烟碱数量在打顶前变化不大,打顶后急剧增加。激素处理可以降低烟叶烟碱含量。      

Influence of germination on the nutritional quality of Phaseolus vulgaris and Cajanus cajan

Germination is a method that can modify the presence of nutrients and antinutrients in legume seeds. In this study, the changes in trypsin inhibitors activity (TIA), phytic acid, tannins, ascorbic acid, thiamine, protein digestibility and minerals in germinated black beans (Phaseolus vulgaris L.), white beans (Phaseolus vulgaris L.) and pigeon beans (Cajanus cajan L. Millsp) were evaluated. The ungerminated grains were analysed as control. A significant decrease in the content of TIA of pigeon beans (19.2%), white beans (52.5%) and black beans (25%) was observed. The reduction of phytic acid was more than 40% for the three grains germinated; for the tannins, the reduction was of 14.3% for pigeon beans, 19% for black beans and 36.2% for white beans. Germination increased the protein digestibility in a 2-4% range, and also increased the ascorbic acid by 300% for white beans, by 33% for black beans and by 208% for pigeon beans. The thiamine content increased more than 26.7%. Germination affected the mineral content erratically, depending more on the grain and the type of mineral. These variations in the content of nutrients and antinutrients of the germinated grains are attributed to the joint effect of the germination and previous soaking the grains were subjected to.     

Filter ventilation and nicotine content of tobacco in cigarettes from Canada, the United Kingdom, and the United States

OBJECTIVES: The purpose was to determine filter ventilation and the nicotine content of tobacco and their contribution to machine-smoked yields of cigarettes from the United States, Canada, and the United Kingdom. METHODS: Ninety-two brands of cigarettes (32 American, 23 Canadian, and 37 British brands) were purchased at retail outlets in State College, Pennsylvania, United States, Toronto, Canada, and London, United Kingdom. A FIDUS FDT filter ventilation tester measured the percentage air-dilution from filter vents. High-pressure, liquid chromatography was used to measure the nicotine content of tobacco. Regression techniques were used to examine the contributions of tobacco nicotine content and filter ventilation to machine-smoked yields of tar, nicotine, and carbon monoxide (CO). RESULTS: Ninety-four per cent of the American brands, 91% of the Canadian brands, and 79% of British brands were ventilated. The total nicotine content of tobacco and percent nicotine (by weight of tobacco) averaged 10.2 mg (standard error of the mean (SEM) 0.25, range: 7.2 to 13.4) and 1.5% (SEM 0.03, range 1.2 to 2) in the United States, 13.5 mg (SEM 0.49, range: 8.0 to 18.3) and 1.8% (SEM 0.06, range: 1.0 to 2.4) in Canada, 12.5 mg (SEM 0.33, range: 9 to 17.5) and 1.7% (SEM 0.04, range: 1.3 to 2.4) in the United Kingdom. Multiple regression analyses showed that ventilation was by far the largest factor influencing machine-smoked yields of tar, nicotine, and CO. CONCLUSION: Filter ventilation appears to be the predominant method for reducing machine-smoked yields of tar, nicotine, and CO in three countries. However, some brands contain about twice as much nicotine (total content or percent nicotine) as do others, indicating that tobacco types or blends and tobacco castings can be used to manipulate nicotine content and nicotine delivery of cigarettes.     

烤烟烟碱转运蛋白基因与烟碱积累的相关性研究

解析烟碱转运相关基因对烟碱积累的影响,可为定向改良烟碱性状提供理论指导。本研究对7份烟碱含量不同的烤烟进行水培,检测打顶前后烟碱含量、烟碱合成基因（NtPMT、NtQPT）、烟碱转运基因（NtNUP1、NtJAT1/2、NtMATE1/2）以及囊泡运输调节基因（NtGEF）的表达量变化。经相关分析、主成分分析和相关网络分析表明：（1）烟碱合成基因NtPMT、NtQPT与烟碱转运基因NtNUP1、NtMATE1/2相互促进表达;（2）根部和叶部的主效烟碱转运基因中,NtJAT1是腰叶的主要烟碱转运基因,NtNUP1、NtJAT1、NtMATE1/2在根部对烟碱转运都有贡献,且转运效率依次递减;（3）囊泡运输调节因子NtGEF也能间接影响叶部烟碱积累。因此,在对烟碱性状进行定向改良时,可考虑烟碱合成、转运以及囊泡运输调节因子对烟碱积累的贡献大小。     

白花白肋烟与烟碱转化的关系研究

通过对发现的5株白肋烟B37花色突变株后代的连续观察与研究,结果表明,5株白花突变株当代均为高烟碱转化株;随着世代的增加,白花后代群体花色遗传稳定,高转化率性状更趋于纯合;烟株群体的平均烟碱含量明显下降,降烟碱则明显上升,烟株群体生物碱表现为以降烟碱为主。研究认为,在白肋烟品种中,花色由显性向隐性和烟碱转化率由隐性向显性突变,二者关系密切;在白肋烟新品种选育和品种提纯、繁殖过程中,对白色花冠突变烟株应及时发现、淘汰,对烟碱转化株应随世代跟踪检测,严防群体转化株积累和基因逐渐纯合;利用白花烟草突变株进行新品种选育应在明确其烟碱转化情况后,再确定是否加以利用。