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IntroductionThe state of California has enacted progressive anti-tobacco policies, including Proposition 56 in 2016. In response, the alternative and emerging tobacco product (ATP) industry has increased its political activity. This study explores the association between the proportion of people voting against Proposition 56 and tobacco/ATP retail density.MethodsWe conducted a retrospective analysis using data on licensed California tobacco retailers, which were then cross-referenced for categorization using Yelp. Proportion voting against Proposition 56 was obtained from the Secretary of State's website. A series of linear regression tests were performed between population-normalized retailer density and voting proportion at the county level before and after adjusting for covariates such as age, gender, race/ethnicity and median household income.ResultsThe total number of licensed tobacco retailers increased by 29.31% from 2015 to 2019. Association between proportion voting against Proposition 56 and retail density was significant during voting and during periods of policy implementation and post-implementation (2016-2018) for non-specialized tobacco retailers. For specialized/ATP retailers, significance was only detected during the post-implementation period (2018-2019) after normalization. Proportion voting against Proposition 56 was also a significant predictor of increase in total number of non-specific (β=0.48, p=0.008) as well as specialized tobacco and/or ATP retail storefronts (β=0.21, p=0.001) from 2016 to 2018.ConclusionsThis study provides initial evidence of the association between tobacco retail density and voting patterns for anti-tobacco policy. Future research should examine the role of tobacco retail density on variation in local support for state tobacco control initiatives, including tailoring outreach to specific voting census blocks in communities with heavy retail presence.

Abstract Causal inference represents a rapidly expanding interdisciplinary subfield that involves various assumptions, study designs, and estimation strategies, allowing researchers to establish causal relationships from both clinical trials and observational data. In tobacco research, numerous studies address causal questions, including the contentious issue of whether vaping in nonsmoking youth leads to smoking initiation, known as the “gateway effect.” Determining the effectiveness and safety of many health interventions will continue to rely on observational [mainly longitudinal] data because randomized trials are not always feasible, ethical, or timely. Therefore, review articles that are synthesizing evidence on the gateway effects of electronic nicotine delivery systems [ENDS] on subsequent cigarette smoking must also consider observational studies as first-rate evidence that can help bring together the polarized tobacco research community and help better understand the “gateway effect.” In addition, this will help ongoing efforts to rigorously prevent ENDS use by youth while expanding the cessation potential of ENDS among adult established smokers who are unwilling to quit otherwise. In this commentary, we discuss causal inference tobacco research as one of the public health challenges and provide some recommendations/implications. [ABSTRACT FROM AUTHOR]

Background: Several instruments are widely used for assessing dependence, craving, withdrawal symptoms, and reinforcing effects in users of tobacco- and nicotine-containing products (TNP), including the Fagerström Test for Nicotine Dependence (FTND), Questionnaire of Smoking Urges, original (QSU) and brief (QSU-b) versions; Minnesota Nicotine Withdrawal Scale, original (MNWS) and revised (MNWS-R) versions; and Cigarette Evaluation Questionnaire, original (CEQ) and modified (mCEQ) versions. Although these instruments have been translated extensively, their translations and corresponding measurement properties have not been systematically assessed. This study aimed to (1) identify the translations of these instruments for which psychometric properties have been published, (2) describe the methods used for translation, and (3) describe the measurement properties and the context in which these translations were evaluated (e.g., target population and TNP used). Methods: Embase and MEDLINE databases were systematically searched. Results: While no information could be found for the CEQ/mCEQ, several translations were available for the remaining instruments: FTND, 25; QSU and QSU-b, 4 each; QSU (12-item version), 1; MNWS, 4; and MNWS-R, 1. Cigarette smokers represented the main target population in which the validation studies were conducted. Information about the translation process was reported for 25 translations. In most cases, the properties of the translations mirrored those of the originals. Differential item functioning was explored in only one case. Conclusions: There are few publications describing the measurement properties of the translations of the FTND, QSU/QSU-b, and MNWS/MNWS-R. None of these translations have been validated for TNPs other than cigarettes, which suggests the need for greater development and validation of instruments in this area.

In this short report, I discuss how public health research, its assessment, and its dissemination outside the academy are produced, in part, through emotional circumstances. Using current debates on e-cigarettes as an example, I show that researchers find themselves uncomfortably positioned in complicated moral and affective landscapes, often making it difficult to represent the nuance of their research. I draw from the experiences and discussions of early career researchers to argue that this pressure can be intensified by the influence of senior colleagues, research communities and wider publics. While the social construction of knowledge has been acknowledged within much disciplinary introspection, the emotional and affective dimensions of knowledge production are perhaps under-appreciated and it is those dimensions that this report seeks to foreground. [ABSTRACT FROM AUTHOR]

International and cross-cultural research is critical for understanding multilevel influences on health, health behaviors, and disease. A particularly relevant area of need for such research is tobacco control. The tobacco epidemic is one of the biggest public health threats globally, killing over 7 million people a year. Research critical to addressing this public health problem has leveraged variability in tobacco use, history, product market, and policies across different countries, settings, and populations, particularly in low- and middle-income countries (LMICs) where the tobacco burden is increasing. These efforts are needed in order to advance the science and inform practice and policy in various settings, including the US. Several funding agencies provide support for international research focused on tobacco control in LMICs because of the importance and implications of such research. This paper provides some concrete examples of how such research has advanced our knowledge-base and informed practice and policy globally, particularly in high-income countries including the US. Some prominent themes emphasized in this manuscript include: the development of knowledge regarding the diverse tobacco products on the market; better understanding of tobacco use and its impact among different populations; generating knowledge about the impacts including unintended consequences of tobacco control policy interventions; and better understanding tobacco industry strategies and informing advocacy efforts. In summary, international tobacco control research, particularly in LMICs, is critical in effectively and efficiently building the evidence base to advance tobacco control research, policy, and practice globally, including the US, with the ultimate goal of curbing the tobacco epidemic. [ABSTRACT FROM AUTHOR]

We examined the relationship between the tobacco industry and the journal Regulatory Toxicology and Pharmacology (RTP) using the Truth Tobacco Industry Documents Library and internet sources. We determined the funding relationships, and categorised the conclusions of all 52 RTP papers on tobacco or nicotine between January 2013 and June 2015, as "positive", "negative" or "neutral" for the tobacco industry. RTP's editor, 57% (4/7) of associate editors and 37% (14/38) of editorial board members had worked or consulted for tobacco companies. Almost all (96%, 50/52) of the papers had authors with tobacco industry ties. Seventy-six percent (38/50) of these papers drew conclusions positive for industry; none drew negative conclusions. The two papers by authors not related to the tobacco industry reached conclusions negative to the industry (p < .001). These results call into question the confidence that members of the scientific community and tobacco product regulators worldwide can have in the conclusions of papers published in RTP. [ABSTRACT FROM AUTHOR]

The promotion of cigarette sales has created new opportunities for the development of commercial cigarettes. In the course of the development of cigarettes, logistics distribution is becoming more important. Many scholars at home and abroad are studying how to optimize the logistics distribution, aiming at further improving the delivery efficiency and minimizing the cost of logistics distribution. At this level, the most important thing is the research of vehicle routing problem. Based on the above background, this paper studies the theory of vehicle distribution and combines with practice, taking the logistics distribution route of a tobacco company logistics center as the research object. Aiming at the existing problems in the process of logistics distribution center vehicle, and considering the influence of vehicle delivery time constraints and the demand for goods produced in the time window of factors such as path selection, the author puts the above into consideration in order to solve the problems of mathematical model for vehicle routing problem with the aim of the logistics center construction. Finally, a genetic algorithm is designed to solve the problem, and the path optimization is realized. [ABSTRACT FROM AUTHOR]

Salinity is one of the abiotic factors that most affect crop growth and production. This study focused on the effect of high salinity on the endogenous levels of the signaling molecules hydrogen sulfite (H 2 S) and nitric oxide (NO) in Nicotiana tabacum leaves and the extent of these for the biochemically-driven plant tolerance to such abiotic stress. The NaCl treatment for 10 days led to an expressive augment of H 2 S and NO levels. This increase was correlated with the raise of l -Cys and l -Arg and the induction of l -cysteine desulfhydrase, cyanoalanine synthase, cysteine synthase, nitrate reductase and arginase, enzymes known to be involved in the biosynthesis of H 2 S or NO. The enzymatic antioxidant system (superoxide dismutase and catalase activity) was boosted and the non-enzymatic antioxidant glutathione was intensively oxidized in leaves upon stress allowing plants to cope with oxidative stress. Lower stomatal conductance was observed in stressed plants in comparison with control ones. Moreover, the high activity of antioxidant enzymes and high rate of glutathione oxidation following salt stress were considerably decreased upon NO or H 2 S scavenging. Thus, increment in NO and H 2 S levels and their interplay, along with metabolic and physiological changes, contributed to tobacco survival to extreme salinity conditions. [ABSTRACT FROM AUTHOR]

We aimed to investigate the role of the plasma membrane-localized sucrose/H+symporter gene (NtSUT1) in root elongation growth of tobacco seedlings (Nicotiana tabacumL. cv. Samsun NN) under aluminum (Al) stress, by comparative study between wild-type (WT) tobacco and constructed over-expression (OX) and suppression (RNAi) lines ofNtSUT1, in which the overexpression or suppression ofNtSUT1was controlled by the cauliflower mosaic virus 35S promoter. Seedlings of each line were grown in a nutrient medium (pH 4.5) without or with aluminum chloride (AlCl3). The roots were analyzed to determine the degree of root elongation and the transcript levels ofNtSUT1, soluble sugar content, and cell survival at the root apex. The transcript level ofNtSUT1at the root apex was negatively affected by Al. Compared with WT, OX lines and RNAi lines had higher and lower contents of soluble sugars at the root apex, respectively. Under a 16-h light/8-h dark photoperiod and in the absence of Al, the root elongation rate was similar in OX and WT, but was significantly decreased in RNAi. In the presence of Al, the degree of Al-induced inhibition of root elongation was lower in OX and higher in RNAi than in WT. At the root apex, the initiation of cell death during a 24-h Al treatment was decelerated in OX and accelerated in RNAi, compared with that in WT. The number of live cells remaining at the root apex after the 24-h Al treatment was higher in OX and lower in RNAi than in WT. In the dark, root growth was supported by sucrose supplied in the medium as a substitute for photoassimilate. Under these conditions in the absence or presence of Al, there were strong positive correlations between the transcript level ofNtSUT1, the soluble sugar content at the root apex and the root elongation rate. Together, these results indicate that NtSUT1 at the root apex primarily supports sucrose uptake via the apoplastic pathway, and that sucrose positively affects root elongation. We conclude that overexpression ofNtSUT1at the root apex increases the soluble sugar content, resulting in greater cell survival and root elongation under Al stress, leading to the Al-tolerance phenotype. [ABSTRACT FROM PUBLISHER]

Background: Drought stress is one of the most severe problem limited agricultural productivity worldwide. It has been reported that plants response to drought-stress by sophisticated mechanisms at both transcriptional and posttranscriptional levels. However, the precise molecular mechanisms governing the responses of tobacco leaves to drought stress and water status are not well understood. To identify genes and miRNAs involved in drought-stress responses in tobacco, we performed both mRNA and small RNA sequencing on tobacco leaf samples from the following three treatments: untreated-control (CL), drought stress (DL), and re-watering (WL). Results: In total, we identified 798 differentially expressed genes (DEGs) between the DL and CL (DL vs. CL) treatments and identified 571 DEGs between theWL and DL (WL vs. DL) treatments. Further analysis revealed 443 overlapping DEGs between the DL vs. CL and WL vs. DL comparisons, and, strikingly, all of these genes exhibited opposing expression trends between these two comparisons, strongly suggesting that these overlapping DEGs are somehow involved in the responses of tobacco leaves to drought stress. Functional annotation analysis showed significant up-regulation of genes annotated to be involved in responses to stimulus and stress, (e.g., late embryogenesis abundant proteins and heat-shock proteins) antioxidant defense (e.g., peroxidases and glutathione S-transferases), down regulation of genes related to the cell cycle pathway, and photosynthesis processes. We also found 69 and 56 transcription factors (TFs) among the DEGs in, respectively, the DL vs. CL and the WL vs. DL comparisons. In addition, small RNA sequencing revealed 63 known microRNAs (miRNA) from 32 families and 368 novel miRNA candidates in tobacco. We also found that five known miRNA families (miR398, miR390, miR162, miR166, and miR168) showed differential regulation under drought conditions. Analysis to identify negative correlations between the differentially expressed miRNAs (DEMs) and DEGs revealed 92 mRNA-miRNA interactions between CL and DL plants, and 32 mRNA-miRNA interactions between DL and WL plants. Conclusions: This study provides a global view of the transcriptional and the post-transcriptional responses of tobacco under drought stress and re-watering conditions. Our results establish an empirical foundation that should prove valuable for further investigations into the molecular mechanisms through which tobacco, and plants more generally, respond to drought stress at multiple molecular genetic levels. [ABSTRACT FROM AUTHOR]

Stress leads to generation of reactive oxygen species in living cells, which are scavenged by antioxidant enzymes. In the present study, genes encoding for two different antioxidant enzymes, namely cytosolic superoxide dismutase and cytosolic ascorbate peroxidase isolated from salt-tolerant cell lines of Arachis hypogaea, were simultaneously overexpressed in tobacco ( Nicotiana tabacum cv. Xanthi) and the effect of their overexpression on alleviation of salinity stress was evaluated. The co-expression of AhCuZnSOD and AhcAPX in tobacco plants helped the resulting transgenic plants in overcoming salt stress. Compared to the wild-type plants, transgenic plants survived longer periods of salinity stress and displayed improved recovery after removal of the stress. The transgenic tobacco plants exhibited better photosynthetic efficiency, higher germination rate, more chlorophyll content, higher levels of total antioxidant enzyme activities, greater water retention capacity, higher proline accumulation, lower level of malondialdehyde content, and reactive oxygen species accumulation under stress conditions in comparison to the WT plants. Our analysis revealed that combined overexpression of the two antioxidant enzymes improved the salinity tolerance in transgenic plants. [ABSTRACT FROM AUTHOR]

Numerous studies have reported on the heat-inducible deletion of a marker gene in plant transformation. However, these deletions seldom display manifestations that are visible to the naked eye to easily identify whether excision has occurred. In this study, an isopentenyl-transferase ( ipt) gene from Agrobacterium tumefaciens was adopted to render abnormal bunched and underdeveloped leaf phenotypes to transgenic buds and/or shoots, and a synthesized heat shock (HS) promoter HSP70m was used to control the Cre/LoxP recombination system. Results showed that the HSP70m promoter could be highly induced by HS, even reaching the strength of the CaMV 35S promoter. The HSP70m was also sufficiently strong to drive Cre/LoxP system to obtain marker-free tobacco plants, meanwhile ipt-induced abnormal buds and shoots served as a visible selectable marker for transgenics, and normal shoot development after heat shock functioned as a positive selectable marker for removal of marker gene including ipt. This screening method is more convenient than the traditional heat-inducible marker excision system. Therefore, the combination of heat-inducible Cre/LoxP system and ipt selection has the potential to be a reliable tool for generating marker-free transgenic plants in genetic manipulation. [ABSTRACT FROM AUTHOR]

Introduction: Higher tobacco taxes reduce tobacco use. On military installations, cigarettes and other tobacco products are sold tax-free, keeping prices artificially low. Pricing regulations in the military specify that tobacco should be within 5% of the local most competitive price, but prices still average almost 13% lower than those at local Walmarts.Methods: To gain insight into policy leaders' ideas and positions on military tobacco pricing, we interviewed members of the Department of Defense (DoD) Addictive Substances Misuse Advisory Committee and the Advisory Committee on Tobacco about tobacco pricing policies (n = 12).Results: Participants frequently lacked specific knowledge of details of military pricing policy, and the impact higher prices might have on military tobacco use. Most participants thought tobacco should not be sold at military stores, but many also felt that this policy change was unlikely due to tobacco industry pressure, and DoD reliance on tobacco profits to support Morale, Welfare, and Recreation funds.Conclusions: Achieving a tobacco-free military will require changing pricing policy, but this study suggests that for effective implementation, military leadership must also understand and articulate more clearly the rationale for doing so.Implications: Previous work has found that adherence to military tobacco pricing policy is inconsistent at best. This study suggests that lack of knowledge about the policy and conflicting pressures resulting from the funding stream tobacco sales represent extend to high level military policy leaders. Without clearer information and direction, these leaders are unlikely to be able to establish and implement better tobacco pricing policy. [ABSTRACT FROM AUTHOR]

Introduction: The objective of this study was to assess whether the nascent, but rapidly growing e-liquid industry prohibits Internet sales to minors and employs safety measures to prevent accidental poisonings.Methods: A stratified simple random sample (n = 120) was selected from the target population (N = 1107) of US online vendors of e-liquid in July 2015. The vendors were stratified and subsequently oversampled by trade association membership and vendor popularity. Three minors aged 16 to 17, who were supervised by adult research staff, attempted to purchase e-liquid from the 120 online vendors using debit cards issued in their names. Measures included vendors' use of age verification, warning labels on e-liquid bottles, and child-resistant packaging.Results: Statistically significant differences were observed by vendor popularity, but not by membership in a trade association. The differences by vendor popularity, however, occurred for measures that were limited to an age warning and list of ingredients. The most striking finding was the scant vendors (n = 4) who successfully prevented the sale of e-liquid to the minors. In contrast, 87.5% and 53.9% of the bottles contained child-resistant packaging and a health warning label, respectively.Conclusions: Irrespective of trade association membership or vendor popularity, online vendors of e-liquids are not taking the proper precautions in preventing sales to minors. The FDA's upcoming deeming rules on e-cigarette products should include explicit requirements for offline and online e-liquid vendors, particularly the use of effective age verification, warning labels, and child-resistant packaging.Implications: This study demonstrates that, in the absence of any current FDA regulation of e-liquid products, self-regulation among vendors is not effective in preventing product acquisition by minors. Lax oversight of the e-liquid industry may draw consumers to bypass current tobacco control restrictions implemented in face-to-face sales settings. As a consequence, there may be an increase in online sales to minors. Further regulation of the industry may increase the already prevalent use of child-resistant packaging, leading to fewer cases of accidental nicotine poisoning. [ABSTRACT FROM AUTHOR]

The CYP82E4v1 gene was identified to encode nicotine demethylase, which catalyzed the conversion of nicotine to nornicotine. In this study, we constructed CYP82E4v1 -RNAi vector and genetically transformed tobacco variety K326. The determination results of nicotine and nornicotine content via HPLC demonstrated that there was significant increase of nicotine content and reduction of nornicotine content in transgenic plants compared with those in wild-type plants. Exogenous application of IAA or GA 3 could reduce the nicotine content in tobaccos, while ABA or 6-BA could increase the content of nicotine. And the more significant difference of nicotine content change in transgenic plants. Aphid-inoculation experiment demonstrated the number of aphid population in transgenic plants was significantly lower than wild-type plants at 12 d after aphid-inoculation. Meanwhile, the activity of AOEs and PAL in transgenic and wild-type tobacco plants after aphid-inoculation was measured. At 3 d after aphid-inoculation, both AOEs and PAL activity were significantly higher than controls, including wild-type plants with aphid-inoculation and transgenic plants with mock-inoculation. Also, the relative expression of these genes involved in salicylic acid/jasmonic acid (SA/JA) signaling pathways was analyzed at different stages after aphid-inoculation and the results demonstrated that there was significantly higher expression of JA-induced LOX gene in both transgenic and wild-type plants inoculated by aphid than the non-inoculated ones while no significant difference in the expression of SA-induced PR-1a gene among them was found, which indicated the JA-mediated resistance response was activated during aphid infestation. Moreover, although the expression level of BGL (another JA-induced gene) was less significant between the two inoculated tobaccos, it was significantly higher than the plant without inoculation, which was 1.4 and 2.2 folds higher than the non-inoculated controls respectively. To sum up, the improvement of aphid-resistance in transgenic tobaccos was based on nicotine accumulation which might cause nerve and antifeed toxicity and JA-mediated resistance response by enhancing the activities of AOEs and PAL. [ABSTRACT FROM AUTHOR]

Topoisomerases are unique enzymes having an ability to remove or add DNA supercoils and untangle the snarled DNA. They can cut, shuffle, and religate DNA strands and remove the torsional stress during DNA replication, transcription or recombination events. In the present study, we over-expressed topoisomerase II (TopoII) in tobacco (Nicotiana tabaccum) and examined its role in growth and development as well as salt (NaCl) stress tolerance. Several putative transgenic plants were generated and the transgene integration and expression was confirmed by PCR and Southern blot analyses, and RT-PCR analysis respectively. Percent seed germination, shoot growth, and chlorophyll content revealed that transgenic lines over-expressing the NtTopoIIα-1 gene exhibited enhanced tolerance to salt (150 and 200 mM NaCl) stress. Moreover, over-expression of TopoII lead to the elevation in proline and glycine betaine levels in response to both concentrations of NaCl as compared to wild-type. In response to NaCl stress, TopoII over-expressing lines showed reduced lipid peroxidation derived malondialdehyde (MDA) generation. These results suggest that TopoII plays a pivotal role in salt stress tolerance in plants. [ABSTRACT FROM AUTHOR]

Context Electronic cigarettes are currently polarizing professional opinion. Some public health experts regard them as an effective smoking cessation aid and a vital means of reducing active and passive smoking, while others regard them as another attempt by the tobacco industry to create new customers and addicts. These different attitudes unsurprisingly yield different conclusions regarding both the appropriate regulation of e-cigarettes and the ethical status of research funded by, or conducted in, cooperation with the tobacco industry. Aim This paper examines whether e-cigarette research linked to the tobacco industry should be regarded as an exception to the rule that tobacco industry research is so tainted by conflicts of interest that journals should refuse to publish them, or at the very least treat them as a special case for scrutiny. Results Despite the fact that e-cigarettes can be used for smoking cessation, most of the conflicts of interest that apply to other tobacco research also apply to e-cigarette research linked to that industry. Conclusion Journals that currently refuse to publish findings from studies linked to tobacco companies have no reason to make an exception in the case of e-cigarettes. [ABSTRACT FROM AUTHOR]

An ultrasensitive method for the simultaneous analysis of pesticides residues in tobacco was developed with online size exclusion chromatography with gas chromatography and tandem mass spectrometry. Tobacco samples were extracted with the solvent mixture of cyclohexane and acetone (7:3, v/v) and centrifuged. Then, the supernatant liquors were injected directly into the online size exclusion chromatography with gas chromatography and tandem mass spectrometry without any other purification procedures after being filtered with a 0.22 μm organic phase filter. The matrix interferences were effectively removed and recoveries of most pesticides were in the range of 72-121%. Especially, for chlorothalonil, the analysis efficiency of this method was much more favorable than that of the general method, in which dispersive solid-phase extraction was used as an additional purified procedure. In addition, the limits of quantitation of this method were from 1 to 50 μg/kg. Therefore, a rapid, cost-effective, labor-saving method was proposed in the present work, which was suitable for the analysis of 41 pesticide residues in tobacco. [ABSTRACT FROM AUTHOR]

Key message: The tobacco plants transformed with popW gene showed enhanced drought tolerance, and the mechanism was found with primed antioxidant defenses and reduced drought stress damages in the transgenic lines. Abstract: Harpin proteins are elicitors produced by several gram-negative plant pathogenic bacteria, triggering multiple beneficial responses in plants, such as induction of defense response against diverse pathogens and insects, growth promotion, and drought tolerance. In this study, the harpin-encoding gene popW derived from Ralstonia solanacearum ZJ3721 was transferred to tobacco. We examined the tolerance of transgenic tobacco plants toward drought stress under greenhouse conditions and analyzed the molecular mechanisms underlying the enhanced drought tolerance. The results revealed that the transgenic lines primed antioxidant defenses and reduced drought stress damages. In addition, they displayed lower malondialdehyde and relative electrical conductivity, while higher relative water content and recovery intension than the tobacco plants transformed with empty vector pBI121 and the wild-type (WT) plants under drought stress. Furthermore, the transgenic lines displayed a significant increase in peroxidase, superoxide dismutase, catalase activities, and ascorbic acid content compared with control plants under drought stress, and these levels were up to 1.95, 1.68, 1.34, and 1.43 times higher than those of WT plants, respectively. Overexpression of popW in tobacco also significantly enhanced the relative transcript levels of oxidative stress-responsive genes NtAPX, NtCAT1, NtGST, and NtCu/Zn- SOD under drought stress. The relative transcript levels of these genes in the transgenic line PW12 were up to 1.94, 2.36, 5.24, and 3.62 times higher than those of WT plants, respectively. These results confirmed that the popW gene, which was transformed into tobacco primed antioxidant responses, increased tolerance to drought stress in tobacco plants. [ABSTRACT FROM AUTHOR]

Current anthropological investigations of smoking offer limited insights into the practice, as they fail to account for how smokers and smoke itself draw things together that are assumed or desired to be kept apart. One of the qualities of smoke is its capacity to link disparate temporalities, spaces, and persons, whether or not connections between them are desirable. Smokers, themselves, too, draw together things as ostensibly different as cautionary public health information about smoking with its potentialities. The capability of smoke and smokers to connect disparate things tends to be overlooked in prevailing presentday anthropological analyses. This occurs when anthropologists align with public health approaches that privilege cessation agendas, rather than taking an independent approach that is anthropologically curious. [ABSTRACT FROM AUTHOR]

The mitogen-activated protein kinases (MAPKs/MPKs) are important factors in the regulation of signal transduction in response to biotic and abiotic stresses. Previously, we characterized a MAPK from tobacco, Nicotiana tabacum MPK4 (NtMPK4). Here, we found a highly homologous gene, NtMPK4-like (NtMPK4L), in tobacco as well as other species in Solanaceae and Gramineae. Deduced amino acid sequences of their translation products carried MEY motifs instead of conserved TXY motifs of the MAPK family. We isolated the full length NtMPK4L gene and examined the physiological functions of NtMPK4L. We revealed that NtMPK4L was activated by wounding, like NtMPK4. However, a constitutively active salicylic acid-induced protein kinase kinase (SIPKKEE), which phosphorylates NtMPK4, did not phosphorylate NtMPK4L. Moreover, a tyrosine residue in the MEY motif was not involved in NtMPK4L activation. We also found that NtMPK4L-silenced plants showed rapid transpiration caused by remarkably open stomata. In addition, NtMPK4L-silenced plants completely lost the ability to close stomata upon ozone treatment and were highly sensitive to ozone, suggesting that this atypical MAPK plays a role in ozone tolerance through stomatal regulation. [ABSTRACT FROM AUTHOR]

An ultrasound-microwave synergistic extraction coupled to headspace solid-phase microextraction was first employed to determine the volatile components in tobacco samples. The method combined the advantages of ultrasound, microwave, and headspace solid-phase microextraction. The extraction, separation, and enrichment were performed in a single step, which could greatly simplify the operation and reduce the whole pretreatment time. In the developed method, several experimental parameters, such as fiber type, ultrasound power, and irradiation time, were optimized to improve sampling efficiency. Under the optimal conditions, there were 37, 36, 34, and 36 components identified in tobacco from Guizhou, Hunan, Yunnan, and Zimbabwe, respectively, including esters, heterocycles, alkanes, ketones, terpenoids, acids, phenols, and alcohols. The compound types were roughly the same while the contents were varied from different origins due to the disparity of their growing conditions, such as soil, water, and climate. In addition, the ultrasound-microwave synergistic extraction coupled to headspace solid-phase microextraction method was compared with the microwave-assisted extraction coupled to headspace solid-phase microextraction and headspace solid-phase microextraction methods. More types of volatile components were obtained by using the ultrasound-microwave synergistic extraction coupled to headspace solid-phase microextraction method, moreover, the contents were high. The results indicated that the ultrasound-microwave synergistic extraction coupled to headspace solid-phase microextraction technique was a simple, time-saving and highly efficient approach, which was especially suitable for analysis of the volatile components in tobacco. [ABSTRACT FROM AUTHOR]

Main conclusion: The heterologous expression of AtPCS1 in tobacco plants exposed to arsenic plus cadmium enhances phytochelatin levels, root As/Cd accumulation and pollutants detoxification, but does not prevent root cyto-histological damages. High phytochelatin (PC) levels may be involved in accumulation and detoxification of both cadmium (Cd) and arsenic (As) in numerous plants. Although polluted environments are frequently characterized by As and Cd coexistence, how increased PC levels affect the adaptation of the entire plant and the response of its cells/tissues to a combined contamination by As and Cd needs investigation. Consequently, we analyzed tobacco seedlings overexpressing Arabidopsis phytochelatin synthase1 gene ( AtPCS1) exposed to As and/or Cd, to evaluate the levels of PCs and As/Cd, the cyto-histological modifications of the roots and the Cd/As leaf extrusion ability. When exposed to As and/or Cd the plants overexpressing AtPCS1 showed higher PC levels, As plus Cd root accumulation, and detoxification ability than the non-overexpressing plants, but a blocked Cd-extrusion from the leaf trichomes. In all genotypes, As, and Cd in particular, damaged lateral root apices, enhancing cell-vacuolization, causing thinning and stretching of endodermis initial cells. Alterations also occurred in the primary structure region of the lateral roots, i.e., cell wall lignification in the external cortex, cell hypertrophy in the inner cortex, crushing of endodermis and stele, and nuclear hypertrophy. Altogether, As and/or Cd caused damage to the lateral roots (and not to the primary one), with such damage not counteracted by AtPCS1 overexpression. The latter, however, positively affected accumulation and detoxification to both pollutants, highlighting that Cd/As accumulation and detoxification due to PCS1 activity do not reduce the cyto-histological damage. [ABSTRACT FROM AUTHOR]

Background: Auxin was recognized as a secondary dormancy phytohormone, controlling seed dormancy and germination. However, the exogenous auxin-controlled seed dormancy and germination remain unclear in physiological process and gene network. Results: Tobacco seeds soaked in 1000 mg/l auxin solution showed markedly decreased germination compared with that in low concentration of auxin solutions and ddH2O. Using an electron microscope, observations were made on the seeds which did not unfold properly in comparison to those submerged in ddH2O. The radicle traits measured by WinRHIZO, were found to be also weaker than the other treatment groups. Quantified by ELISA, there was no significant difference found in β-1,3glucanase activity and abscisic acid (ABA) content between the seeds imbibed in gradient concentration of auxin solution and those soaked in ddH2O. However, gibberellic acid (GA) and auxin contents were significantly higher at the time of exogenous auxin imbibition and were gradually reduced at germination. RNA sequencing (RNA-seq), revealed that the transcriptome of auxin-responsive dormancy seeds were more similar to that of the imbibed seeds when compared with primary dormancy seeds by principal component analysis. The results of gene differential expression analysis revealed that auxin-controlled seed secondary dormancy was associated with flavonol biosynthetic process, gibberellin metabolic process, adenylyl-sulfate reductase activity, thioredoxin activity, glutamate synthase (NADH) activity and chromatin regulation. In addition, auxin-responsive germination responded to ABA, auxin, jasmonic acid (JA) and salicylic acid (SA) mediated signaling pathway (red, far red and blue light), glutathione and methionine (Met) metabolism. Conclusions: In this study, exogenous auxin-mediated seed secondary dormancy is an environmental model that prevents seed germination in an unfavorable condition. Seeds of which could not imbibe normally, and radicles of which also could not develop normally and emerge. To complete the germination, seeds of which would stimulate more GA synthesis to antagonize the stimulation of exogenous auxin. Exogenous auxin regulates multi-metabolic networks controlling seed secondary dormancy and germination, of which the most important thing was that we found the auxin-responsive seed secondary dormancy refers to epigenetic regulation and germination to enhance Met pathway. Therefore, this study uncovers a previously unrecognized transcriptional regulatory networks and physiological development process of seed dormancy and germination with superfluous auxin signal activate. [ABSTRACT FROM AUTHOR]

Background: The Tobacco Longitudinal Care study was a randomized controlled trial for smoking cessation. It demonstrated that longitudinal care for smoking cessation, in which telephone-based counseling and nicotine replacement therapy were offered for 12 months, was more effective than the standard 8-week treatment.Purpose: This study aims to identify for whom and how longitudinal care increased the likelihood of abstinence.Methods: Mediated moderation analyses were utilized across three time points.Results: There was a trend towards smokers who did not respond to treatment (i.e., were still smoking) by 21 days being more likely to be abstinent at 6 months if they received longitudinal care rather than usual care. Similarly, those who did not respond to treatment by 3 months were more likely to be abstinent at 12 months if they received longitudinal care. At both time points, the likelihood of abstinence did not differ across treatment conditions among participants who responded to treatment (i.e., quit smoking). The effect on 6-month outcomes was mediated by satisfaction and readiness to quit. Cessation self-efficacy, satisfaction, and readiness to quit mediated the effect on 12-month outcomes. The effect of treatment condition on the likelihood of abstinence at 18 months was not moderated by response to treatment at 6 months.Conclusions: Smokers who did not respond to initial treatment benefited from longitudinal care. Differential effects of treatment condition were not observed among those who responded to early treatment. Conditional assignment to longitudinal care may be useful. Determining for whom and how interventions work over time will advance theory and practice. [ABSTRACT FROM AUTHOR]

Background: Pseudomonas syringae pv. tabaci (Pst), which is the pathogen responsible for tobacco wildfire disease, has received considerable attention in recent years. The objective of this study was to clarify the responses of photosystem I (PSI) and photosystem II (PSII) to Pst infection in tobacco leaves. Results: The net photosynthetic rate (Pn) and carboxylation efficiency (CE) were inhibited by Pst infection. The normalized relative variable fluorescence at the K step (Wk) and the relative variable fluorescence at the J step (VJ) increased while the maximal quantum yield of PSII (Fv/Fm) and the density of QA-reducing PSII reaction centers per cross section (RC/CSm) decreased, indicating that the reaction centers, and the donor and acceptor sides of PSII were all severely damaged after Pst infection. The PSI activity decreased as the infection progressed. Furthermore, we observed a considerable overall degradation of PsbO, D1, PsaA proteins and an over-accumulation of reactive oxygen species (ROS). Conclusions: Photoinhibition and photoinhibition-like damage were observed under light and dark conditions, respectively, after Pst infection of tobacco leaves. The damage was greater in the dark. ROS over-accumulation was not the primary cause of the photoinhibition and photoinhibition-like damage. The PsbO, D1 and PsaA proteins appear to be the targets during Pst infection under light and dark conditions. [ABSTRACT FROM AUTHOR]

Objectives: Risk perception measures of tobacco products relative to cigarettes are used commonly and are important to tobacco research, given that they may be associated with, and predict, tobacco use. However, results may differ based on the actual measures used. This study compares direct and indirect approaches to measuring e-cigarette/cigarette risk perceptions. Methods: We compared the responses of 519 current smokers on a nationally-representative 2014 survey that gauged perceptions of e-cigarettes' harm relative to cigarettes in 2 ways: (1) a single-item direct measure of comparative harm; and (2) a 2-item indirect measure (which measured perceived levels of harm from e-cigarettes and cigarettes independently in 2 parallel questions). Results: We found that 60% of smokers rated e-cigarettes "less harmful" than cigarettes when using a direct comparative risk measure versus 73% when using an indirect measure. Agreement between measure types was fair (Cohen's kappa=0.45) and was lower for males, Blacks, older smokers, and less educated smokers. Conclusions: E-cigarettes were more likely to be rated by smokers as less harmful than cigarettes when using indirect versus direct measures. Additional methodologic research in this area is warranted given the importance of risk perceptions to tobacco control interventions, communications, policymaking, and regulation. [ABSTRACT FROM AUTHOR]

[Objective] The aim was to study the growth and quality characteristics of sun-cured tobacco Kadsura Coccinea in Guangchang County and give full play to its advantages. [Method] The research took tobacco varieties including Tiechi in Yiqian, Mushao in Yangxi Tiechi in Chishui, and Liuye in Toupo as test materials to explore development process, quality characteristics and economic traits of different varieties. [Result] The variety of Tiechi in Yiqian had medium growht, moderate growth periods, and the best economic benefits. Total content of aroma matter was the highest in the varieties of Tiechi in Yiqian. Also it had more content of products of browning reaction and products degraded by cembranoids. Besides, volume and quality of aroma were higher, as well as the score of sensory quality. [Conclusion] Comprehensive comparisons suggested that the variety of Tiechi in Yiqian was superior to others at tobacco-growing, economic benefits and quality. [ABSTRACT FROM AUTHOR]

In order to explore the most suitable mode for the primary processing model of reconstituted tobacco, another two kinds of conditioning process schemes for reconstituted tobacco were designed based on the existing reconstituted tobacco processing method. Comparative analysis and evaluation were conducted for moisture content uniformity, intrinsic chemical compositions, casing uniformity, blending uniformity and sensory quality of the samples from the three kind of processing modes. The results showed that loosing and conditioning or the vacuum conditioning pretreatment of the reconstituted tobacco could effectively reduce the difference in moisture content during the blending, and improve the casing uniformity and blending uniformity. Moreover, the samples with the loosing and conditioning pretreatment had higher total sugar and reducing sugar contents, which indicated that the loosing and conditioning pretreatment method was more favorable for the improvement of the intrinsic quality of cigarettes. In addition, the three kinds of aromatic components contents of cigarettes using the loosing and conditioning pretreatment were higher, and the casing uniformity, blending uniformity and overall sensory quality of this pretreatment were all superior to that of the other two kinds of reconstituted tobacco pretreatment methods. The contents of total sugar, reducing sugar as well as the three kinds of aromatic components of cigarettes processed with vacuum conditioning pretreatment were all slightly lower than those of the existing methods, but the casing uniformity and blending uniformity were improved, while it showed small difference in the sensory quality with the existing processing method. [ABSTRACT FROM AUTHOR]

The appearance quality, physical properties, chemical components and sensory quality of 69 flue-cured tobacco leaf samples from 6 counties of Fuzhou City in 2013 were analyzed and evaluated, and were compared with those in southeast area of China. The results showed that the flue-cured tobacco leaves in Fuzhou in 2013 had better hygroscopicity, toughness and filling ability, as well as suitable dragging force. However, some of the tobacco leaves were slightly thin, and had relatively high stem ratio. The tobacco leaves in Fuzhou had higher potassium content, lower starch content, and higher potassium to chlorine ratio. The middle tobacco leaves had better coordination of chemical components and general sensory quality (medium to medium-super level). Most upper and middle flue-cured tobacco leaf samples had medium-super aroma quality, relatively sufficient aroma quantity, and relatively concentrated smoke; while the lower flue-cured tobacco leaves had little aroma quantity and insufficient smoke. The appearance quality score of lower tobacco leaf samples in Fuzhou in 2013 was slightly lower than that in southeastand whole China. The scores of maturity and leaf structure of middle tobacco leaves in Fuzhou were equivalent to those in southeast China and the national averages. The upper leaves in Fuzhou obtained an equivalent score in oil content and slightly lower scores in other indexes as compared with those in southeast China. The middle-lower tobacco leaves in Fuzhou had better hygroscopicity and toughness compared with those in southeastand whole China. The total alkaloid content per plant andreducing sugar content and potassium content in the middle and lower parts were higher than those in southeast and whole China. However, the scores of coordination of chemical components of lower and upper tobacco leaves in Fuzhou were slightly lower than those in southeast and whole China. The sensory quality of the 3 parts of tobacco leaves in Fuzhou were similar to that in southeast and whole China, but the score of consistency of upper tobacco leaves in Fuzhou was slightly higher. [ABSTRACT FROM AUTHOR]

Introduction: In this study, penalized imputation (PI), a common approach to handle missing smoking status data and sometimes referred to as "missing=smoking," is compared with other missing data approaches using data from internet-based smoking cessation trials. Two hypotheses were tested: (1) PI leads to more conservative effect estimates than complete observations analysis; and (2) PI and multiple imputation (MI) lead to similar effect estimates under balanced (equal missingness proportions among the trial arms) and unbalanced missingness.Methods: First, the outcomes of 22 trials included in a recent Cochrane review on internet-based smoking cessation interventions were reanalyzed using only the complete observations, and after applying PI. Second, in a simulation study outcomes under PI, complete observations analysis, and two types of MI were compared. For this purpose, individual patient data from one of the Cochrane review trials were used. Results of the missing data approaches were compared with reference data without missing observations, upon which balanced and unbalanced missingness scenarios were imposed.Results: In the reanalysis of 22 trials, relative risks (RR = 1.15 [1.00; 1.33]) after PI were nearly identical to those under complete observations analysis (RR = 1.14 [0.98; 1.32]). In the simulation study, PI was the only approach that led to deviations from the reference data beyond its 95% confidence interval.Conclusions: Analyses after PI led to pooled results equivalent to complete observations analyses. PI also led to significant deviations from the reference in the simulation studies. PI biases the reported effects of interventions, favoring the condition with the lowest proportion of missingness. Therefore, more sophisticated missing data approaches than PI should be applied. [ABSTRACT FROM AUTHOR]

Background: Assessment of health-related quality of life (HRQoL) is well established in clinical research, but ceiling effects in validated tools might prevent detection of changes in well respondents. Tobacco Quality of Life Impact Tool (TQOLITv1) uses conceptual and psychometric advances to enhance detection of HRQoL changes.Methods: In a 6-month, forced-switch study, the German TQOLITv1 was assessed in healthy adult (age 23-55 years) current and matched former-smokers. At baseline, smokers were switched to reduced toxicant prototype (RTP) or conventional cigarette for 6 months. TQOLITv1 responses were collected at baseline, 3 and 6 months from current smokers whilst former smokers completed it at the latter two time points. TQOLITv1 includes SF-36v2 and new smoking-specific, physical and general-health measures.Results: Reliability at baseline was good (Cronbach's coefficient alpha > 0.70) for all measures. The baseline percentage with the best possible score (ceiling effect) for former and current smokers was substantially better for the new physical function than SF-36 physical function measure (35% vs. 59% at ceiling, respectively). New smoking-specific measures discriminated current from former smokers better than general health measures. Smoking-specific symptoms (r = 0.73) were more stable from baseline to 6 months than other measures (r = 0.38-0.54) particularly more than the SF-36 mental component score (r = 0.24). Although both product smoking groups worsened in most HRQoL measures, changes in general and smoking-specific HRQoL impact measures favored RTP smokers.Conclusions: The German TQOLITv1 is sufficiently reliable and valid to assess HRQoL and may be more useful than SF-36v2 in evaluation of interventions in well smoking populations including those consuming RTPs. [ABSTRACT FROM AUTHOR]

Background: Computer technologies hold promise for implementing tobacco screening, brief intervention, and referral to treatment (SBIRT). This study aims to evaluate a computerized tobacco SBIRT system called the Health Evaluation and Referral Assistant (HERA). Methods: Smokers (n = 421) presenting to an emergency department were randomly assigned to the HERA or a minimal-treatment Control and were followed for 3 months. Analyses compared smoking cessation treatment provider contact, treatment initiation, treatment completion, and smoking behavior across condition using univariable comparisons, generalized estimating equations (GEE), and post hoc Chi square analyses. Results: HERA participants were more likely to initiate contact with a treatment provider but did not differ on treatment initiation, quit attempts, or sustained abstinence. Subanalyses revealed HERA participants who accepted a faxed referral were more likely to initiate treatment but were not more likely to stop smoking. Conclusions: The HERA promoted initial contact with a smoking cessation provider and the faxed referral further promoted treatment initiation, but it did not lead to improved abstinence. Trial registration: ClinicalTrials.gov number NCT01153373 [ABSTRACT FROM AUTHOR]

Key message: The IbAGP1 gene of sweet potato ( Ipomoea batatas ) encodes the sucrose-inducible small subunit of ADP-glucose pyrophosphorylase. Through expression analysis of 5′-truncations and synthetic forms of the IbAGP1 promoter in transgenic tobacco, we show that SURE-Like elements and W-box elements of the promoter contribute to the sucrose inducibility of this gene. Abstract: Sweet potato ( Ipomoea batatas) contains two genes ( IbAGP1 and IbAGP2) encoding the catalytically active small subunits of ADP-glucose pyrophosphorylase, an enzyme with an important role in regulating starch synthesis in higher plants. Previous studies have shown that IbAGP1 is expressed in the storage roots, leaves, and stem tissues of sweet potato, and its transcript is strongly induced by applying sucrose exogenously to detached leaves. To investigate the tissue-specific expression of the IbAGP1 promoter, a series of 5′-truncated promoters extending from bases −1913, −1598, −1298, −1053, −716, and −286 to base +75 were used to drive the expression of the β-glucuronidase reporter gene ( GUS) in tobacco plants ( Nicotiana tabacum). Histochemical and fluorometric GUS assays showed that (1) GUS expression driven by the longest fragment (1989 bp) of the IbAGP1 promoter was detected in vegetative tissues (roots, stems, leaves), (2) fragments extending to −1053 or beyond retained strong GUS expression in roots, stems, and leaves, whereas further 5′-deletions resulted in considerable reduction in GUS activity, and (3) the series of 5′-truncated promoters responded differently to exogenously applied sucrose. The 1989-bp IbAGP1 promoter contains five sequences (two AATAAAA, one AATAAAAAA, and two AATAAATAAA) that are similar to sucrose-responsive elements (SURE). These SURE-Like sequences are found at nucleotide positions −1273, −1239, −681, −610, and −189. Moreover, putative W-box elements are found at positions −1985, −1434, −750, and −578. Synthetic promoters containing tandem repeats of the 4X SURE-Like or 4X W-box upstream from a minimal CaMV35S promoter- GUS fusion showed significant expression in transgenic tobacco in response to exogenous sucrose. These results show that SURE-Like elements and W-box elements of the IbAGP1 promoter contribute to the sucrose inducibility of this gene. [ABSTRACT FROM AUTHOR]

Key message: Overexpression of the iron transporter NtPIC1 increases iron concentration in shoots and reduces Cd uptake/accumulation in plants, mediating tolerance to cadmium. Abstract: Cadmium (Cd) is toxic to plant cells and causes plants to display a typical iron (Fe) deficiency phenotype. NtPIC1 (Permease In Chloroplast1) is an Fe transporter protein in tobacco, required for Fe homeostasis. Based on preliminary results in transformed Saccharomyces cerevisiae BY4741 cells, which showed that NtPIC1 expression increased Cd tolerance, this study evaluated Cd tolerance in tobacco plants overexpressing NtPIC1 (NtPIC1-OE). We show that these plants have longer roots and higher fresh weights than wild-type (WT) plants after Cd exposure. Under Cd stress, WT plants display more chlorosis, stronger growth inhibition, and lower chlorophyll concentrations than NtPIC1-OE plants. Importantly, NtPIC1-OE plants had higher Fe concentrations in shoots and lower Fe concentrations in roots, and Cd concentrations in NtPIC1-OE plants were significantly lower compared to those in WT plants. Moreover, Fe transport-related genes ( NtPIC1, NtNRAMP1, and NtFER1) were upregulated in NtPIC1-OE plants, while Fe deficiency-related genes ( NtFRO1, NtIRT1, and NtZIP1) that mediate Cd uptake were downregulated. We also found that the activities of several antioxidative enzymes were significantly higher in NtPIC1-OE plants than in WT plants under Cd stress. Overall, our results demonstrate that overexpression of NtPIC1 is an efficient way to increase shoot Fe concentrations and reduce Cd uptake/accumulation in plants. [ABSTRACT FROM AUTHOR]

A randomized, multi-center study of adult cigarette smokers switched to tobacco-heating cigarettes, snus or ultra-low machine yield tobacco-burning cigarettes (50/group) was conducted, and subjects’ experience with the products was followed for 24 weeks. Differences in biomarkers of tobacco exposure between smokers and never smokers at baseline and among groups relative to each other and over time were assessed. Results indicated reduced exposure to many potentially harmful constituents found in cigarette smoke following product switching. Findings support differences in exposure from the use of various tobacco products and are relevant to the understanding of a risk continuum among tobacco products (ClinicalTrials.gov Identifier: NCT02061917). [ABSTRACT FROM PUBLISHER]

A randomized, multi-center study was conducted to assess potential improvement in health status measures, as well as changes in biomarkers of tobacco exposure and biomarkers of biological effect, in current adult cigarette smokers switched to tobacco-heating cigarettes, snus or ultra-low machine yield tobacco-burning cigarettes (50/group) evaluated over 24 weeks. Study design, conduct and methodology are presented here along with subjects’ disposition, characteristics, compliance and safety results. This design and methodology, evaluating generally healthy adult smokers over a relatively short duration, proved feasible. Findings from this randomized study provide generalized knowledge of the risk continuum among various tobacco products (ClinicalTrials.gov Identifier: NCT02061917). [ABSTRACT FROM PUBLISHER]

Introduction Smoking and depression have a long-history documented of comorbidity. Objective The objective of this study was to develop and test a treatment that could simultaneously achieve smoking abstinence and decrease depressive symptoms in a group of heavy smokers with minimal/mild depressive symptomatology. Method Sixty smokers were randomly assigned to three different treatment settings. Treatment included a pre-abstinence phase, a psychological treatment phase, a pharmacotherapy phase and a follow-up stage. Smokers began the psychological treatment and the pharmacotherapy two weeks before the day they chosen to quit smoking, and monitoring was conducted over a year. Abstinence was confirmed by assessing the levels of urinary cotinine. Results Using a linear mixed model with individual random effect, baseline data was compared with subsequent assessments; 46% of the patients achieved abstinence. For men, the three treatment settings significantly reduced depressive symptoms and helped smokers to achieve abstinence. For women, only the nicotine patch showed to be effective in the reducing depressive symptoms. Discussion and conclusion Integral pre-abstinence treatment is effective in aiding smokers to achieve smoking abstinence and improve depressive symptoms. [ABSTRACT FROM AUTHOR]

Anthranilate synthase (AS), a tetramer consisting of two α subunits and two β subunits, is the key control enzyme in the tryptophan (Trp) biosynthesis pathway. A naturally occurring α subunit of AS called ASA2 that is insensitive to Trp feedback inhibition was isolated from a tobacco suspension cell culture and has been extensively studied and used for both nuclear and plastid transformation. However, the obligate β subunit of AS had not been studied in tobacco. Therefore, the tobacco AS β subunit-encoding cDNA was cloned and its encoded protein was verified. Agrobacterium-mediated transformation of tobacco plants was performed, under the selection of the toxic Trp analogs, 7-methyltryptophan or α-methyltryptophan, with a construct containing both ASA2 and AS β subunit genes. Many transgenic plants overexpressing both subunits were identified and examined. Compared to the wild-type plants, the transgenic plants had higher levels of enzymatic activities for both holoenzyme and α subunit. The transgenic plants had 9 to 68 times the amount of free Trp as the wild-type plants, which was more pronounced than plants overexpressing ASA2 alone. This study demonstrates the potential of co-expressing AS α and β subunits as a robust plant transformation system as well as overcoming feedback inhibition to obtain high levels of Trp biosynthesis. [ABSTRACT FROM AUTHOR]

The present study aims to analyze the effect of bacterial volatiles on tobacco callus organogenesis. A glass prototype was designed in the shape of the letter 'H' such that plants and bacteria could be grown in physically separated compartments while volatile compounds could still be exchanged. Volatiles from a beneficial bacterium, Bacillus badius M12, which showed growth promotion in Sesamum indicum (sesame), also induced organogenesis in tobacco callus. Volatiles from B. badius M12 appeared to maintain tobacco callus in a green and viable state during the prolonged, 45 d, sealed incubation. This apparent antioxidant effect was investigated by exposing freshly cut cylinders of apple flesh, a tissue noted for its ready tendency to oxidize, to bacterial volatiles. The expression of superoxide dismutase (SOD), a key antioxidant enzyme, was higher in callus exposed to bacterial volatiles, confirming that they enhanced antioxidant activity. Exposure of apple tissues to volatile compounds from B. badius M12 and a well-known growth-promoting bacterial volatile, 2,3-butanediol, led to increased antioxidant activity. We conclude that plant growth-promoting bacterial volatiles were useful in tissue organogenesis and increased antioxidant activity. [ABSTRACT FROM AUTHOR]