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An efficient and sensitive analytical method based on precolumn derivatization and gas chromatography—mass spectrometry—selected ion monitoring (GC—MS—SIM) was proposed and validated for analysis of two cembrenediols (CBDs) which are α-cembrenediol and β-cembrenediol in tobacco samples. CBDs in tobacco samples were extracted by sonication with 50 mL dichloromethane for 10 min before derivatized with 2:3 (v/v) bis(trimethylsilyl)trifluoroacetamide (BSTFA)—pyridine at 20 °C for 100 min. CBDs’ level in tobacco samples was analyzed by GC—MS—SIM and quantified by the internal standard method. The linear range for α-CBD and β-CBD was 13.6–554.6 μg mL−1 and 4.11–162.6 μg mL−1, and the correlation coefficients of both were 0.9998. The limit of detection (LOD) and limit of quantification (LOQ) of α-cembrenediol and β-cembrenediol were 0.40 μg g−1 and 1.34 μg g−1, and 0.27 μg g−1 and 0.90 μg g−1, respectively. Average recoveries of α-CBD and β-CBD were 94.4–99.9% and 91.9–98.2% while the relative standard deviations (RSDs, n = 5) were ranged from 2.67 to 5.6% and 2.04 to 4.22%, respectively. This proposed analytical method has been successfully applied to analyze CBDs in tobacco samples.

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. Air Pollution and Plant Life 2004 Borowiak, K. (2005) Visible leaf injury of tobacco plants caused by tropospheric ozone in the

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A. Rodgman and T. A. Perfetti, The chemical components of tobacco and tobacco smoke, Taylor & Francis, Boca Raton, FL, 2008, pp. 780–789 Perfetti T. A

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Turšić, I. (1994): Comparative investigation on different basic ploughing depths and nitrogen fertilizer rates for virginia tobacco. Agric. Conspec. Sci. , 59 , 5-20. Comparative

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Fatty acid hydroperoxide-producing lipoxygenase (LOX) and hydroperoxide-degrading glutathione peroxidase (GPOX) enzyme activities were studied in leaves of virus resistant Xanthi-nc and susceptible Samsun-nn tobacco cultivars after inoculation with Tobacco mosaic virus (TMV). Total LOX activity showed a maximum at pH 5.5 in cell-free extracts of uninfected leaves. LOX activity markedly increased at this pH after TMV inoculation, but a substantial induction was detected also in the basic pH range with an emerging peak around pH = 8.5. TMV-elicited LOX induction was weaker and appeared later in Samsun-nn than in Xanthi-nc leaves. GPOX activity was also substantially induced by TMV infection. However, this induction appeared only 4 days post-inoculation in resistant Xanthi-nc plants in tissues surrounding the localized necrotic lesions. In contrast, GPOX activity did not change in TMV-inoculated, susceptible Samsun-nn leaves. Several glutathione S-transferase (GST) isoenzymes also display GPOX activity. The expression of a tau class GST gene was markedly induced by TMV inoculation in Xanthi-nc leaves. This tobacco GST gene was partially cloned and sequenced.

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Based on many sources, the paper makes an attempt to identify the social effects produced by the rising use of coffee and tobacco in the Balkans, and to mark out similarities and differences with respect to associated developments in other parts of the Ottoman Empire and in the European countries. The Balkans was a very interesting contact zone where influences of two civilisations intermingled and where all developments were largely dependent on the attitude of the majority population, the non-Muslim Ottoman subjects.

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Abstract

Background

Obsessive-compulsive disorder (OCD) is a biologically heterogeneous neuropsychiatric disorder. It is associated with impulsive as well as compulsive neurocognitive mechanisms. Cigarette smoking is common among most psychiatric patients; however, OCD patients are thought to show reduced rates. OCD smokers may thus represent a relatively uncommon OCD subtype, characterised by increased impulsivity. In this study, we aim to establish the prevalence of smoking in a large, well-defined OCD cohort. We investigate whether smokers with OCD differ from non-smokers with OCD on clinical measures of behavioural impulsivity and domains of personality and temperament, including reward-dependence and novelty-seeking.

Method

183 of 200 outpatients with DSM-IV OCD were interviewed to determine smoking status. A sub-sample of 10 smokers was compared with 10 non-smokers, pair wise matched for age and gender. Patients were assessed for DSM co-morbidity, symptom profile, OCD severity, behavioural impulsivity and personality dimensions.

Results

Only 10 individuals (5.46%; five males) were smokers. Compared to OCD non-smokers, OCD smokers scored significantly higher on the Barratt Impulsiveness Scale (p < 0.001). They also scored significantly higher on TCI measures of novelty seeking (p < 0.001) and reward dependence (p < 0.001) and significantly lower on measures of harm avoidance (p < 0.001).

Conclusions

Tobacco smoking is rare in OCD. Significantly higher levels of behavioural impulsivity and temperamental factors associated with reward driven impulsivity are seen in OCD smokers compared to non-smokers. Tobacco smoking may indicate a possible source of neurocognitive heterogeneity in OCD.

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Tomato spotted wilt virus (TSWV) is spread by Thrips tabaci tabaci nominate subspecies in the field under climatic conditions of Carpathian Basin. The overwintered females harbouring the pathogen proved to be the most important vector in the outbreak of epidemics in the tobacco growing district. Among the numerous host plants, the winter annual and the perennial weeds provide the survival of the pathogen. Infected weeds as Asclepias syriaca, Convolvulus arvensis grown in vineyards far from the tobacco fields and greenhouses indicate the wide spread of TSWV. Chickweed (Stellaria media) being a suitable host both for TSWV and the overwintering T. tabaci specimens constitutes the most dangerous source of epidemics. As a result of the common effect of the application of insecticides in accordance with the monitoring of T. tabaci, the centralized cultivation of the seedlings and the weed-free surroundings of the nurseries, the occurrence of TSWV was reduced to the minimum level in tobacco fields.

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, 11 ]. It still remains a great challenge to selectively and effectively enrich the specific food VOCs by use of efficient sampling methods. Tobacco and tobacco products as a special kind of food have a wide range of consumers around the world. Tobacco

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The monoterpenoid (S)-carvone was shown earlier to induce glutathione S-transferase (GST) activity and to attenuate necrotic lesion formation in Tobacco mosaic virus (TMV) inoculated, hypersensitively reacting tobacco Xanthi-nc plants. To explore structure-activity relationships, three monoterpenes and five monoterpenoids were tested for their ability to induce increased GST activity in tobacco leaf discs. (S)-Carvone proved to be the most potent inducer. (S)-Carvone treatments markedly up-regulated the expression of several tobacco GST genes belonging to the phi, tau and theta classes, particularly in the case of tau class GSTs. Furthermore, TMV inoculation slightly induced the transcript abundance of the GSTT2 gene. The expression of three catalase (CAT) genes was also examined in (S)-carvone-treated tobacco leaf discs. The expression of CAT1 was not influenced by (S)-carvone treatments, whereas that of CAT2 was significantly repressed. (S)-Carvone very weakly induced the transcription of the CAT3 gene. The effect of the opposite enantiomer, (R)-carvone on the expression of GST and CAT genes was similar to that of (S)-carvone. Our results suggest that the antioxidative reactions catalyzed by tau and theta class GSTs contribute to the attenuation of necrotic disease symptoms in TMV-inoculated tobacco plants.

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