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1.
Funct Plant Biol ; 512024 05.
Article in English | MEDLINE | ID: mdl-38743838

ABSTRACT

Soil salinisation is an important abiotic stress faced in grape cultivating, leading to weakened plant vigour and reduced fruit quality. Melatonin as a novel hormone has shown positive exogenous application value. Therefore, this study used wine grape (Vitis vinifera ) 'Pinot Noir' as a test material to investigate the changes of foliar spraying with different concentrations of melatonin on the physiology and fruit quality of wine grapes in a field under simulated salt stress (200mmolL-1 NaCl). The results showed that foliar spraying of melatonin significantly increased the intercellular CO2 concentration, maximum photochemical quantum yield of PSII, relative chlorophyll and ascorbic acid content of the leaves, as well as the single spike weight, 100-grain weight, transverse and longitudinal diameters, malic acid, α-amino nitrogen and ammonia content of fruits, and decreased the initial fluorescence value of leaves, ascorbate peroxidase activity, glutathione content, fruit transverse to longitudinal ratio and tartaric acid content of plants under salt stress. Results of the comprehensive evaluation of the affiliation function indicated that 100µmolL-1 melatonin treatment had the best effect on reducing salt stress in grapes. In summary, melatonin application could enhance the salt tolerance of grapes by improving the photosynthetic capacity of grape plants under salt stress and promoting fruit development and quality formation, and these results provide new insights into the involvement of melatonin in the improvement of salt tolerance in crop, as well as some theoretical basis for the development and industrialisation of stress-resistant cultivation techniques for wine grapes.


Subject(s)
Fruit , Melatonin , Photosynthesis , Plant Leaves , Salt Stress , Vitis , Vitis/drug effects , Vitis/physiology , Vitis/growth & development , Melatonin/pharmacology , Melatonin/administration & dosage , Fruit/drug effects , Fruit/growth & development , Salt Stress/drug effects , Plant Leaves/drug effects , Photosynthesis/drug effects , Chlorophyll/metabolism , Ascorbic Acid/pharmacology , Wine
2.
JMIR Form Res ; 8: e49276, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38723251

ABSTRACT

BACKGROUND: Open-system electronic cigarette (EC) product features, such as battery capacity, maximum output wattage, and so forth, are major components that drive product costs and may influence use patterns. Moreover, continued innovation and monitoring of product features and prices will provide critical information for designing appropriate taxation policies and product regulations. OBJECTIVE: This study will examine how product features are associated with the prices of devices sold in web-based vape shops. METHODS: We draw samples from 5 popular, US-based, web-based vape shops from April to August 2022 to examine starter kits, device-only products, and e-liquid container-only products. We implemented a linear regression model with a store-fixed effect to examine the association between device attributes and prices. RESULTS: EC starter kits or devices vary significantly by type, with mod prices being much higher than pod and vape pen prices. The prices of mod starter kits were even lower than those of mod devices, suggesting that mod starter kits are discounted in web-based vape shops. The price of mod kits, mod device-only products, and pod kits increased as the battery capacity and output wattage increased. For vape pens, the price was positively associated with the volume size of the e-liquid container. On the other hand, the price of pod kits was positively associated with the number of containers. CONCLUSIONS: A unit-based specific tax, therefore, will impose a higher tax burden on lower-priced devices such as vape pens or pod systems and a lower tax burden on mod devices. A volume- or capacity-based specific tax on devices will impose a higher tax burden on vape pens with a larger container size. Meanwhile, ad valorem taxes pegged to wholesale or retail prices would apply evenly across device types, meaning those with advanced features such as higher battery capacities and output wattage would face higher rates. Therefore, policy makers could manipulate tax rates by device type to discourage the use of certain device products.

3.
medRxiv ; 2024 Apr 05.
Article in English | MEDLINE | ID: mdl-38633785

ABSTRACT

Background: Over 20 states and local jurisdictions in the U.S. have imposed e-cigarette taxes. It is important to evaluate how adult vapers, including those who also smoke respond to e-cigarette taxation. The purpose of this study is to examine factors associated with adult vapers' cost perception of e-cigarettes relative to cigarettes and budget allocations between two products. Methods: We recruited a nationally representative sample of 801 adult e-cigarette users in the U.S., who participated in an online survey in April and May 2023. Nested-ordered logit models and ordinary least squares regressions were used in the analysis. Results: On average, monthly e-cigarette spending was $82.22, and cigarette spending was $118.77 among dual users. Less frequent e-cigarette use and higher state-level e-cigarette taxes were associated with perceiving smoking as cheaper than vaping. Age and exclusive use of tank systems were associated with perceiving vaping as cheaper than smoking. Exclusive use of tank systems was also associated with lower e-cigarette spending. Adults who used e-cigarettes more frequently preferred to report weekly budget on e-cigarettes ( p < 0.01), and among dual users, everyday smokers preferred to report weekly (versus monthly) budget on cigarettes compared to someday smokers ( p < 0.001). Conclusion: Among US adult vapers, frequencies of tobacco use and e-cigarette device type are closely related to cost measures; and e-cigarette taxes are associated with cost perception of e-cigarettes relative to cigarettes, suggesting potential financial disincentive for vaping. Policymaker may consider imposing differential taxes by e-cigarette product types due to their different costs to consumers.

4.
JMIR Form Res ; 8: e47570, 2024 Feb 28.
Article in English | MEDLINE | ID: mdl-38416562

ABSTRACT

BACKGROUND: Prior studies have demonstrated that the e-cigarette market contains a large number of brands. Identifying these existing e-cigarette brands is a key element of market surveillance, which will further assist in policy making and compliance checks. OBJECTIVE: To facilitate the surveillance of the diverse product landscape in the e-cigarette market, we constructed a semantic database of e-cigarette brands that have appeared in the US market as of 2020-2022. METHODS: In order to build the brand database, we searched and compiled e-cigarette brands from a comprehensive list of retail channels and sources, including (1) e-liquid and disposable brands sold in web-based stores, (2) e-cigarette brands sold in brick-and-mortar stores and collected by the Nielsen Retail Scanner Data, (3) e-cigarette brands compiled by Wikipedia, (4) self-reported e-cigarette brands from the 2020 International Tobacco Control Four-Country Smoking and Vaping (ITC 4CV) US survey, and (5) e-cigarette brands on Twitter. We also estimated the top 5 e-cigarette brands by sales volume in brick-and-mortar stores, by the frequency and variety of offerings in web-based shops, and by the frequency of self-reported brands from the 2020 ITC 4CV US survey. RESULTS: As of 2020-2022, a total of 912 e-cigarette brands have been sold by various retail channels. During 2020-2022, the top 5 brands are JUUL, vuse, njoy, blu, and logic in brick-and-mortar stores; blu, king, monster, twist, and air factory for e-liquids in web-based stores; hyde, pod mesh, suorin, vaporlax, and xtra for disposables sold in web-based stores; and smok, aspire, vaporesso, innokin, and eleaf based on self-reported survey data. CONCLUSIONS: As the US Food and Drug Administration enforces the premarket tobacco market authorization, many e-cigarette brands may become illegal in the US market. In this context, how e-cigarette brands evolve and consolidate in different retail channels will be critical for understanding the regulatory impacts on product availability. Our semantic database of e-cigarette brands can serve as a useful tool to monitor product and marketplace development, conduct compliance checks, assess manufacturers' marketing behaviors, and identify regulatory impacts.

5.
JMIR Form Res ; 8: e49031, 2024 Jan 24.
Article in English | MEDLINE | ID: mdl-38265858

ABSTRACT

BACKGROUND: From 2016 to 2021, the volume of peer-reviewed publications related to tobacco has experienced a significant increase. This presents a considerable challenge in efficiently summarizing, synthesizing, and disseminating research findings, especially when it comes to addressing specific target populations, such as the LGBTQ+ (lesbian, gay, bisexual, transgender, queer, intersex, asexual, Two Spirit, and other persons who identify as part of this community) populations. OBJECTIVE: In order to expedite evidence synthesis and research gap discoveries, this pilot study has the following three aims: (1) to compile a specialized semantic database for tobacco policy research to extract information from journal article abstracts, (2) to develop natural language processing (NLP) algorithms that comprehend the literature on nicotine and tobacco product use among sexual and gender diverse populations, and (3) to compare the discoveries of the NLP algorithms with an ongoing systematic review of tobacco policy research among LGBTQ+ populations. METHODS: We built a tobacco research domain-specific semantic database using data from 2993 paper abstracts from 4 leading tobacco-specific journals, with enrichment from other publicly available sources. We then trained an NLP model to extract named entities after learning patterns and relationships between words and their context in text, which further enriched the semantic database. Using this iterative process, we extracted and assessed studies relevant to LGBTQ+ tobacco control issues, further comparing our findings with an ongoing systematic review that also focuses on evidence synthesis for this demographic group. RESULTS: In total, 33 studies were identified as relevant to sexual and gender diverse individuals' nicotine and tobacco product use. Consistent with the ongoing systematic review, the NLP results showed that there is a scarcity of studies assessing policy impact on this demographic using causal inference methods. In addition, the literature is dominated by US data. We found that the product drawing the most attention in the body of existing research is cigarettes or cigarette smoking and that the number of studies of various age groups is almost evenly distributed between youth or young adults and adults, consistent with the research needs identified by the US health agencies. CONCLUSIONS: Our pilot study serves as a compelling demonstration of the capabilities of NLP tools in expediting the processes of evidence synthesis and the identification of research gaps. While future research is needed to statistically test the NLP tool's performance, there is potential for NLP tools to fundamentally transform the approach to evidence synthesis.

6.
Tob Control ; 2023 Aug 28.
Article in English | MEDLINE | ID: mdl-37640531

ABSTRACT

BACKGROUND: How excise taxes are passed through to prices determines whether tax policies will be effective in changing smoking behaviours. Though previous literature has documented that cigarette taxes are overly shifted to prices, there is limited evidence on how cigarette tax pass-through to prices is affected by the uptake and evolution of e-cigarettes (ECs) in the US market. OBJECTIVE: This study investigates how cigarette excise tax pass-through rate varied by price levels (the 25th, 50th, and 75th percentile prices) and the uptake and evolution of ECs. METHODS: Tax pass-through rates were assessed using ordinary least squares regressions while controlling for state, year and month fixed effects. Different trends were then tested for the pre-EC uptake era (2006-2011), EC uptake era (2012-2016) and the evolution of nicotine salt-based ECs era (2017 and later). FINDINGS: Cigarette excise taxes were fully shifted to the 25th and 50th percentile prices and overly shifted to the 75th percentile prices at a 1:1.1 rate. While cigarette excise taxes had a continuous impact on raising prices, the tax pass-through rates were lower for lower priced cigarettes, and states imposed lower taxes. CONCLUSIONS: Continuing to raise cigarette taxes may be needed to create financial incentives to encourage people who smoke to switch to ECs. In addition, continuing to raise cigarette taxes and additional pricing policies such as price promotion restrictions are needed to increase retail prices and reduce price minimisation opportunities.

7.
Physiol Plant ; 175(3): e13950, 2023.
Article in English | MEDLINE | ID: mdl-37291799

ABSTRACT

Plant acclimation to salt and alkali stress is closely linked to the ability of the antioxidant system to mediate the scavenging of reactive oxygen species (ROS). In this study, we investigated the effects of salt stress and alkali stress on ROS, antioxidant enzymes, transcriptome, and metabolome. The results showed that the levels of superoxide anions, hydrogen peroxide, malondialdehyde, and electrolyte leakage increased under salt and alkali stress, with higher concentrations observed under alkali stress than salt stress. The activities of superoxide dismutase (EC 1.15.1.1), peroxidase (EC 1.11.1.7), catalase (EC 1.11.1.6), ascorbate peroxidase (EC 1.11.1.11), glutathione reductase (EC 1.6.4.2), dehydroascorbate reductase (EC 1.8.5.1), and monodehydroascorbate reductase (EC 1.6.5.4) varied under salt and alkali stress. The transcriptome analysis revealed the induction of signal transduction and metabolic processes and differential expression of genes encoding antioxidant enzymes in response to salt and alkali stress. The metabolome analysis demonstrated increased ascorbic acid and glutathione under salt stress, while most phenolic acids, flavonoids, and alkaloids increased under salt and alkali stress. Integrative analysis of the metabolome and transcriptome data revealed that the flavonoid biosynthesis pathway played a key role in the grapevine's response to salt stress. The total flavonoid content increased under salt and alkali stress, but the accumulation of flavonoids was higher under salt stress than alkali stress. In conclusion, our findings indicate significant differences in the antioxidant defense of grapevines under these two stresses, providing insight into distinct acclimation mechanisms in grapevine under salt and alkali stress.


Subject(s)
Antioxidants , Oxidative Stress , Antioxidants/metabolism , Reactive Oxygen Species/metabolism , Transcriptome , Superoxide Dismutase/metabolism , Metabolome
8.
Prev Med Rep ; 33: 102222, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37181243

ABSTRACT

Synthetic nicotine (relative to tobacco-derived, or "natural" nicotine) is an emerging feature of e-cigarettes including e-liquids in the online marketplace. This study investigated a total of 11,161 unique nicotine e-liquids sold in online stores in the US during 2021, using keyword matching approach to identify the feature of synthetic nicotine based on product description texts. We showed that in 2021, 2.13% of nicotine-containing e-liquids in our sample were marketed as synthetic nicotine e-liquids. About a quarter of the synthetic nicotine e-liquids that we identified were salt-based; the nicotine strength varied; and those synthetic nicotine e-liquids had a variety of flavor profiles. Synthetic nicotine containing e-cigarettes are likely to remain in the market and manufacturers might market those products as "tobacco-free," to attract consumers who this feature as healthier or less addictive. It is important to monitor synthetic nicotine in the e-cigarette marketplace and assess how this feature influences consumer behaviors.

9.
Tob Control ; 2023 May 17.
Article in English | MEDLINE | ID: mdl-37197949

ABSTRACT

INTRODUCTION: The present study empirically examined the association between price discounts and product attributes of e-liquids sold by online retailers. METHODS: We analysed 14 000 e-liquid products from five major online e-cigarette retailers between April and May 2021 to determine the association between price discounts and product attributes such as nicotine level and form, flavour and vegetable glycerine/propylene glycol ratio. A fixed-effects model was used in the analysis and discounts were calculated in US cents/mL of e-liquid volume. RESULTS: Out of 14 407 e-liquid products, 92.5% were offered at a discounted price. On average, the price discount for the 13 324 products that had discounts was 16.84 cents/mL across the five stores. Among the three forms of nicotine (salt, freebase and nicotine free), salt e-liquids had the highest average price discount. CONCLUSION: Our findings suggest that e-liquids with salt nicotine have a higher average price discount when sold online, which may influence consumer purchasing behaviour. Further research is needed to assess the potential impact of these discounts on youth and adult tobacco use. Policymakers may consider implementing measures to limit online price discounts for e-liquids as a means of reducing sales among young people.

10.
PLoS One ; 18(5): e0286258, 2023.
Article in English | MEDLINE | ID: mdl-37235576

ABSTRACT

Given the increase in electronic cigarette use during the past decade, the objectives of this study are to obtain comprehensive product-level information from online vape shops, which are one of the most common outlets for e-cigarette users to purchase vaping products, especially e-liquid products, and to examine the appeal of various e-liquid product attributes to consumers. We used web scraping and estimation of generalized estimating equation (GEE) models to obtain and analyze data from five popular online vape shops that sell nationwide across the US. The outcome measures are e-liquid pricing for the following e-liquid product attributes: nicotine concentration (in mg/ml), nicotine form (nicotine-free, freebase, or salt), vegetable glycerin/propylene glycol (VG/PG) ratio, and a variety of flavors. We find that the pricing for freebase nicotine and nicotine salt products are 1% (p<0.001) lower and 12% higher (p<0.001), respectively, than that for products that do not contain nicotine. For nicotine salt-based e-liquid products specifically, the pricing for a 50/50 VG/PG ratio is 10% (p<0.001) higher than the pricing for a more common 70/30 VG/PG ratio, and the pricing for fruity flavors is 2% (p<0.05) higher than that for tobacco/unflavored products. Regulating the nicotine form in all e-liquid products and fruity flavor in nicotine salt-based products will have a great impact on the market and consumers. The preference for VG/PG ratio varies by product nicotine form. More evidence on typical user patterns of a certain nicotine form (i.e., freebase or salt nicotine) is needed to assess the public health consequences of these regulations.


Subject(s)
Electronic Nicotine Delivery Systems , Tobacco Products , Vaping , Nicotine , Sodium Chloride, Dietary , Vegetables , Sodium Chloride
11.
BMC Plant Biol ; 23(1): 226, 2023 Apr 28.
Article in English | MEDLINE | ID: mdl-37106450

ABSTRACT

BACKGROUND: Continuous cropping is a significant obstacle to sustainable development in the pea (Pisum sativum L.) industry, but the underlying mechanisms of this remain unclear. In this study, we used 16 S rDNA sequencing, transcriptomics, and metabolomics to analyze the response mechanism of roots and soil bacteria to continuous cropping and the relationship between soil bacteria and root phenotypes of different pea genotypes (Ding wan 10 and Yun wan 8). RESULTS: Continuous cropping inhibited pea growth, with a greater effect on Ding wan 10 than Yun wan 8. Metabolomics showed that the number of differentially accumulated metabolites (DAMs) in pea roots increased with the number of continuous cropping, and more metabolic pathways were involved. Transcriptomics revealed that the number of differentially expressed genes (DEGs) increased with the number of continuous cropping. Continuous cropping altered the expression of genes involved in plant-pathogen interaction, MAPK signal transduction, and lignin synthesis pathways in pea roots, with more DEGs in Ding wan 10 than in Yun wan 8. The up-regulated expression of genes in the ethylene signal transduction pathway was evident in Ding wan 10. Soil bacterial diversity did not change, but the relative abundance of bacteria significantly responded to continuous cropping. Integrative analysis showed that the bacteria with significant relative abundance in the soil were strongly associated with the antioxidant synthesis and linoleic acid metabolism pathway of pea roots under continuous cropping once. Under continuous cropping twice, the bacteria with significant relative abundance changes were strongly associated with cysteine and methionine metabolism, fatty acid metabolism, phenylpropanoid biosynthesis, terpenoid backbone biosynthesis, linoleic acid, and amino sugar and nucleotide sugar metabolism. CONCLUSION: Ding wan 10 was more sensitive to continuous cropping than Yun wan 8. Continuous cropping times and pea genotypes determined the differences in root metabolic pathways. There were common metabolic pathways in the two pea genotypes in response to continuous cropping, and the DEGs and DAMs in these metabolic pathways were strongly associated with the bacteria with significant changes in relative abundance in the soil. This study provides new insights into obstacles to continuous cropping in peas.


Subject(s)
Pisum sativum , Soil , Pisum sativum/genetics , Linoleic Acid , Soil Microbiology , Bacteria , Transcription, Genetic
12.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(3): 302-307, 2023 Mar 15.
Article in Chinese | MEDLINE | ID: mdl-36940988

ABSTRACT

Objective: To prepare a new plastic bone filler material with adhesive carrier and matrix particles derived from human bone, and evaluate its safety and osteoinductive ability through animal tests. Methods: The human long bones donated voluntarily were prepared into decalcified bone matrix (DBM) by crushing, cleaning, and demineralization, and then the DBM was prepared into bone matrix gelatin (BMG) by warm bath method, and the BMG and DBM were mixed to prepare the experimental group's plastic bone filler material; DBM was used as control group. Fifteen healthy male thymus-free nude mice aged 6-9 weeks were used to prepare intermuscular space between gluteus medius and gluteus maximus muscles, and all of them were implanted with experimental group materials. The animals were sacrificed at 1, 4, and 6 weeks after operation, and the ectopic osteogenic effect was evaluated by HE staining. Eight 9-month-old Japanese large-ear rabbits were selected to prepare 6-mm-diameter defects at the condyles of both hind legs, and the left and right sides were filled with the materials of the experimental group and the control group respectively. The animals were sacrificed at 12 and 26 weeks after operation, and the effect of bone defect repair were evaluated by Micro-CT and HE staining. Results: In ectopic osteogenesis experiment, HE staining showed that a large number of chondrocytes could be observed at 1 week after operation, and obvious newly formed cartilage tissue could be observed at 4 and 6 weeks after operation. For the rabbit condyle bone filling experiment, HE staining showed that at 12 weeks after operation, part of the materials were absorbed, and new cartilage could be observed in both experimental and control groups; at 26 weeks after operation, the most of the materials were absorbed, and large amount of new bone could be observed in the 2 groups, while new bone unit structure could be observed in the experimental group. Micro-CT observation showed that the bone formation rate and area of the experimental group were better than those of the control group. The measurement of bone morphometric parameters showed that the parameters at 26 weeks after operation in both groups were significantly higher than those at 12 weeks after operation ( P<0.05). At 12 weeks after operation, the bone mineral density and bone volume fraction in the experimental group were significantly higher than those in the control group ( P<0.05), and there was no significant difference between the two groups in trabecular thickness ( P>0.05). At 26 weeks after operation, the bone mineral density of the experimental group was significantly higher than that of the control group ( P<0.05). There was no significant difference in bone volume fraction and trabecular thickness between the two groups ( P>0.05). Conclusion: The new plastic bone filler material is an excellent bone filler material with good biosafety and osteoinductive activity.


Subject(s)
Plastics , Tissue Engineering , Mice , Animals , Male , Humans , Rabbits , Child , Tissue Engineering/methods , Mice, Nude , Bone and Bones , Cartilage , Osteogenesis , Gelatin
13.
Physiol Plant ; 175(2): e13896, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36951039

ABSTRACT

Salt stress is a dominant environmental factor that restricts the growth and yield of crops. Nitrogen is an essential mineral element for plants, regulates various physiological and biochemical processes, and has been reported to enhance salt tolerance in plants. However, the crosstalk between salt and nitrogen in grapes is not well understood. In this study, we found that nitrogen supplementation (0.01 and 0.1 mol L-1 NH4 NO3 ) significantly increased the accumulation of proline, chlorophyll, Na+ , NH4 + , and NO3 - , while it reduced the malondialdehyde content and inhibited photosynthetic performance under salt stress conditions (200 mmol L-1 NaCl). Further transcriptome and metabolome analyses showed that a total of 4890 differentially expressed genes (DEGs) and 753 differently accumulated metabolites (DAMs) were identified. Joint omics results revealed that plant hormone signal transduction pathway connected the DEGs and DAMs. In-depth analysis revealed that nitrogen supplementation increased the levels of endogenous abscisic acid, salicylic acid, and jasmonic acid by inducing the expression of 11, 4, and 13 genes related to their respective biosynthesis pathway. In contrast, endogenous indoleacetic acid content was significantly reduced due to the remarkable regulation of seven genes of its biosynthetic pathway. The modulation in hormone contents subsequently activated the differential expression of 13, 10, 12, and 29 genes of the respective downstream hormone signaling transduction pathways. Overall, all results indicate that moderate nitrogen supplementation could improve salt tolerance by regulating grape physiology and endogenous hormone homeostasis, as well as the expression of key genes in signaling pathways, which provides new insights into the interactions between mineral elements and salt stress.


Subject(s)
Hormones , Salt Tolerance , Vitis , Gene Expression Regulation, Plant , Hormones/metabolism , Nitrogen/metabolism , Salt Tolerance/genetics , Seedlings/metabolism , Vitis/metabolism
14.
Tob Control ; 32(e2): e160-e165, 2023 08.
Article in English | MEDLINE | ID: mdl-34937806

ABSTRACT

BACKGROUND: A growing number of states or jurisdictions in the USA have imposed excise taxes on electronic nicotine delivery systems (ENDS). However, there is no consensus on how best to tax ENDS. OBJECTIVES: We specifically compare the tax incidence or burden for ENDS and cigarettes and analyse how ENDS tax incidence is associated with the choices of tax bases and rates. METHODS: We calculate ENDS excise tax incidence as the percentage of retail prices for each state or jurisdiction. Next, we use ordinary least squares to evaluate how tax incidence is associated with the choices of tax bases (eg, a specific tax base vs a value or ad valorem tax base) and rates and how these associations are moderated by product types. RESULTS: ENDS and cigarette tax incidence is similar at the state level. Nonetheless, when federal cigarette taxes are considered, the cigarette tax incidence is higher than the tax incidence on closed-system ENDS. The proportion of states that impose value taxes is higher for open systems (65.4%) than for closed systems (46.2%). A value tax base is associated with a 7 percentage point lower tax incidence compared with a specific tax base. Product type further moderates the association between tax base and incidence. CONCLUSION: Tax incidence can be used to measure the strength of ENDS tax policies and how they are compared with cigarette taxes. Policymakers who aim to prevent youth from using ENDS may consider a value tax base to raise the tax incidence of closed systems-the product type preferred by young people.


Subject(s)
Electronic Nicotine Delivery Systems , Tobacco Products , Humans , United States/epidemiology , Adolescent , Incidence , Taxes , Marketing , Commerce
15.
Plants (Basel) ; 13(1)2023 Dec 29.
Article in English | MEDLINE | ID: mdl-38202414

ABSTRACT

To investigate the mechanism of melatonin (MT)-mediated glutathione (GSH) in promoting glucoraphanin (GRA) and sulforaphane (SF) synthesis, the gene expression pattern and protein content of hairy broccoli roots under MT treatment were analyzed by a combination of RNA-seq and tandem mass spectrometry tagging (TMT) techniques in this study. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that both proteins and mRNAs with the same expression trend were enriched in the "Glutathione metabolism (ko00480)" and "Proteasome (ko03050)" pathways, and most of the differentially expressed genes (DEGs) and differentially abundant proteins (DAPs) regulating the two pathways were downregulated. The results showed that endogenous GSH concentration and GR activity were increased in hairy roots after MT treatment. Exogenous GSH could promote the biosynthesis of GRA and SF, and both exogenous MT and GSH could upregulate the expression of the GSTF11 gene related to the sulfur transport gene, thus promoting the biosynthesis of GRA. Taken together, this study provides a new perspective to explore the complex molecular mechanisms of improving GRA and SF synthesis levels by MT and GSH regulation.

16.
BMC Plant Biol ; 22(1): 528, 2022 Nov 14.
Article in English | MEDLINE | ID: mdl-36376811

ABSTRACT

BACKGROUND: Soil salinization and alkalization are widespread environmental problems that limit grapevine (Vitis vinifera L.) growth and yield. However, little is known about the response of grapevine to alkali stress. This study investigated the differences in physiological characteristics, chloroplast structure, transcriptome, and metabolome in grapevine plants under salt stress and alkali stress. RESULTS: We found that grapevine plants under salt stress and alkali stress showed leaf chlorosis, a decline in photosynthetic capacity, a decrease in chlorophyll content and Rubisco activity, an imbalance of Na+ and K+, and damaged chloroplast ultrastructure. Fv/Fm decreased under salt stress and alkali stress. NPQ increased under salt stress whereas decreased under alkali stress. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment showed the differentially expressed genes (DEGs) induced by salt stress and alkali stress were involved in different biological processes and have varied molecular functions. The expression of stress genes involved in the ABA and MAPK signaling pathways was markedly altered by salt stress and alkali stress. The genes encoding ion transporter (AKT1, HKT1, NHX1, NHX2, TPC1A, TPC1B) were up-regulated under salt stress and alkali stress. Down-regulation in the expression of numerous genes in the 'Porphyrin and chlorophyll metabolism', 'Photosynthesis-antenna proteins', and 'Photosynthesis' pathways were observed under alkali stress. Many genes in the 'Carbon fixation in photosynthetic organisms' pathway in salt stress and alkali stress were down-regulated. Metabolome showed that 431 and 378 differentially accumulated metabolites (DAMs) were identified in salt stress and alkali stress, respectively. L-Glutamic acid and 5-Aminolevulinate involved in chlorophyll synthesis decreased under salt stress and alkali stress. The abundance of 19 DAMs under salt stress related to photosynthesis decreased. The abundance of 16 organic acids in salt stress and 22 in alkali stress increased respectively. CONCLUSIONS: Our findings suggested that alkali stress had more adverse effects on grapevine leaves, chloroplast structure, ion balance, and photosynthesis than salt stress. Transcriptional and metabolic profiling showed that there were significant differences in the effects of salt stress and alkali stress on the expression of key genes and the abundance of pivotal metabolites in grapevine plants.


Subject(s)
Vitis , Vitis/metabolism , Gene Expression Regulation, Plant , Alkalies/metabolism , Plant Proteins/genetics , Gene Expression Profiling , Salt Stress/genetics , Transcriptome , Chlorophyll/metabolism
17.
Article in English | MEDLINE | ID: mdl-36360834

ABSTRACT

INTRODUCTION: Electronic cigarettes are the most popular tobacco product among U.S. youth, and over 80% of current youth users of e-cigarettes use flavored e-cigarettes, with fruit, mint/menthol, and candy/sweets being the most popular flavors. A number of new e-liquid flavors are currently emerging in the online e-cigarette market. Menthol and other flavored e-cigarettes could incentivize combustible tobacco smokers to transition to e-cigarette use. METHODS: From February to May 2021, we scraped data of over 14,000 e-liquid products, including detailed descriptions of their flavors, from five national online vape shops. Building upon the existing e-liquid flavor wheel, we expanded the semantic databases (i.e., key terms) to identify flavors using WordNet-a major database for keyword matching and group discussion. Using the enriched databases, we classified 14,000+ e-liquid products into the following 11 main flavor categories: "fruit", "dessert/candy/sweets", "coffee/tea", "alcohol", "other beverages", "tobacco", "mint/menthol", "nuts", "spices/pepper", "other flavors", and "unspecified flavor". RESULTS: We find that the most prominent flavor sold in the five online vape shop in 2021 was fruit flavored products, followed by dessert/candy/other sweets. Online vendors often label a product with several flavor profiles, such as fruit and menthol. CONCLUSIONS: Given that online stores market products with multiple flavor profiles and most of their products contain fruit flavor, the FDA may have issued marketing denial orders to some of these products. It is important to further examine how online stores respond to the FDA flavor restrictions (e.g., compliance or non-compliance).


Subject(s)
Electronic Nicotine Delivery Systems , Tobacco Products , Vaping , Adolescent , Humans , Menthol , Flavoring Agents/analysis
18.
Physiol Mol Biol Plants ; 28(6): 1147-1158, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35910436

ABSTRACT

In higher plants, light capture of chlorophyll a/b binding protein (Lhc) plays a crucial role in the plant's response to adverse environment. So far, the family has not been systematically identified in grapes. In this study, 20 VvLhcs were identified in the grape genome, which were distributed in 13 of 19 grape chromosomes and divided into 7 developing branches. The results of gene duplication analysis showed that 6 VvLhcs formed fragment duplication events, while there was no tandem duplication in VvLhcs. Exon-intron structure analysis showed that they had a wide number of exons. Protein conserved motif analysis showed that VvLhcs contained more similar motif structures in the same phylogenetic branch. The cis-acting elements in the VvLhcs promoter region mainly respond to light, plant hormones and abiotic stresses. In addition, qRT-PCR results showed that different proportions of salt stress and red-blue light affected the expression of VvLhcs and the expression patterns of genes in different grape varieties were different. The results for further study on different grape varieties in different combinations of red and blue light of the Lhc provide a theoretical basis. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01204-5.

19.
BMC Plant Biol ; 22(1): 403, 2022 Aug 17.
Article in English | MEDLINE | ID: mdl-35974315

ABSTRACT

Glucoraphanin (GRA) is present in the seeds and nutrient organs of broccoli and is the precursor of the anti-cancer compound sulforaphane (SF). The hairy roots obtained by infecting broccoli (Brassica oleracea L. var. Italic Planch) leaves with Agrobacterium rhizogenes (ATCC15834) are phytohormonally autonomous, genetically stable, and can produce large amounts of the anti-cancer substance SF. Melatonin (MT) is a natural hormone widely found in plants. Studies have shown that melatonin can regulate the synthesis of secondary metabolites of downstream targets by mediating the synthesis of signal molecules. However, whether MT regulates the synthesis of NO and H2O2 and mediates the synthesis mechanism of secondary metabolites, GRA and SF, is not yet clear. In this study, the hairy roots of broccoli were treated with 500 µmol/L MT, and the genome of broccoli (Brassica oleracea L. var. botrytis L) was used as the reference genome for transcriptome analysis. By this approach, we found that MT regulates the synthesis of NO and H2O2 and mediates the synthesis of secondary metabolites GRA and SF. GO annotations indicated that DEGs involved in the MT treatment of broccoli hairy roots were mainly related to catalytic activity, cells, and metabolic processes; the KEGG pathway analysis indicated that MT treatment likely affects the hormone signal transduction process in broccoli hairy roots; broccoli hairy roots were treated with 500 µmol/L MT for 0, 6, 12, 20, and 32 h, respectively; compared with 0 h, the yield of GRA and SF increased under the other treatments. The highest yields of GRA and SF occurred at 12 h. The NO content was the highest at 12 h, and the H2O2 content was positively correlated with MT concentration. The content of NO and H2O2 were regulated, and the content of GRA and SF was increased under MT treatment. NO synthase inhibitor (L-NAME and TUN) could effectively inhibit the content of NO in broccoli hairy roots and reduce GRA and SF yield; MT could regulate NO levels by regulating NO synthesis-related enzymes and could alleviate the reduction of NO content in tissue cells caused by NO synthase inhibitor and promote NO synthesis. These results have important theoretical implications for understanding the regulation of GRA and SF synthesis events by NO and H2O2.


Subject(s)
Brassica , Melatonin , Brassica/genetics , Brassica/metabolism , Glucosinolates/metabolism , Hydrogen Peroxide/metabolism , Isothiocyanates , Melatonin/metabolism , Nitric Oxide/metabolism , Nitric Oxide Synthase/metabolism , Oximes , Sulfoxides , Transcriptome
20.
J Plant Res ; 135(6): 757-770, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35999478

ABSTRACT

Hairy roots obtained by infecting broccoli (Brassica oleracea var. italica) leaves with Agrobacterium rhizogenes (ATCC15834) have the characteristics of phytohormone autonomy, genetic stability and can produce a large amount of the anti-cancer substance Sulforaphane (SF) and the biosynthetic precursor Glucoraphanin (GRA). Under the induction of the exogenous signaling molecule methyl jasmonate (MeJA), the production of SF in broccoli hairy roots was significantly increased. However, the molecular mechanism of GRA and SF synthesis in hairy roots of broccoli treated with MeJA has not been reported. In this study, according to the yield of GRA and SF, the best concentration of MeJA treatment for hairy roots of broccoli was selected. After 18 days of growth, broccoli hairy roots were treated with 10 mmol L-1 MeJA for 0, 3, 6, 9 and 12 h. Compared with 0 h, the yield of GRA and SF increased under other treatments. The highest yield of GRA and SF occurred at 9 h, which were 2.22-fold and 1.74-fold higher than those at 0 h. Brassica oleracea var. botrytis was used as reference genome, and 5,757 differentially expressed genes (DEG) were observed at 0, 3, 6, 9 and 12 h under 10 mmol L-1 MeJA treatment, of which 4,673 were down-regulated and 1084 were up-regulated. The key genes regulating GRA synthesis, CYP79F1, CYP83A1, UGT74B1, FMOGS-OX5 and GSL-OH, were up-regulated at 0 and 3 h, and down-regulated the rest of the time; BCAT2 was up-regulated at 6, 9, 12 h, and at 0, 3 h expression was down-regulated, transcription factors MYB28 and MYB29 were down-regulated by exogenous MeJA treatment. A pathway of GRA biosynthesis and transformation pathways in MeJA-treated broccoli hairy roots was simulated and the molecular mechanism of GRA biosynthesis and SF accumulation in broccoli hairy roots under MeJA treatment was revealed.


Subject(s)
Brassica , Brassica/genetics , Brassica/metabolism , Gene Expression Profiling
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