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1.
J Chem Ecol ; 46(10): 978-986, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32876829

RESUMO

Herbivory can induce chemical changes throughout plant tissues including flowers, which could affect pollinator-pathogen interactions. Pollen is highly defended compared to nectar, but no study has examined whether herbivory affects pollen chemistry. We assessed the effects of leaf herbivory on nectar and pollen alkaloids in Nicotiana tabacum, and how herbivory-induced changes in nectar and pollen affect pollinator-pathogen interactions. We damaged leaves of Nicotiana tabacum using the specialist herbivore Manduca sexta and compared nicotine and anabasine concentrations in nectar and pollen. We then pooled nectar and pollen by collection periods (within and after one month of flowering), fed them in separate experiments to bumble bees (Bombus impatiens) infected with the gut pathogen Crithidia bombi, and assessed infections after seven days. We did not detect alkaloids in nectar, and leaf damage did not alter the effect of nectar on Crithidia counts. In pollen, herbivory induced higher concentrations of anabasine but not nicotine, and alkaloid concentrations rose and then fell as a function of days since flowering. Bees fed pollen from damaged plants had Crithidia counts 15 times higher than bees fed pollen from undamaged plants, but only when pollen was collected after one month of flowering, indicating that both damage and time since flowering affected interaction outcomes. Within undamaged treatments, bees fed late-collected pollen had Crithidia counts 10 times lower than bees fed early-collected pollen, also indicating the importance of time since flowering. Our results emphasize the role of herbivores in shaping pollen chemistry, with consequences for interactions between pollinators and their pathogens.


Assuntos
Abelhas/parasitologia , Crithidia/fisiologia , Flores/química , Herbivoria , Interações Hospedeiro-Parasita , Nicotiana/química , Anabasina/análise , Animais , Comportamento Alimentar/fisiologia , Manduca/fisiologia , Nicotina/análise , Folhas de Planta/química , Néctar de Plantas/química , Pólen/química , Polinização , Fatores de Tempo
2.
Food Chem Toxicol ; 125: 252-270, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30610935

RESUMO

Swedish snus is a smokeless tobacco product that contains reduced levels of harmful compounds compared with cigarette smoke. In Sweden, where snus use exceeds smoking among men, relatively low rates of major smoking-related diseases have been recorded. To better understand how snus use could align with current tobacco harm reduction strategies, its potential mechanisms of toxicity must be investigated. This study aimed to determine, via a systems toxicology approach, the biological impact of repeated 72-hour exposure of human gingival epithelial organotypic cultures to extracts from both a commercial and a reference snus and the total particulate matter (TPM) from cigarette smoke. At concentrations relevant for human use, cultures treated with snus extracts induced mild, generally reversible biological changes, while TPM treatment induced substantial morphological and inflammatory alterations. Network enrichment analysis and integrative analysis of the global mRNA and miRNA expression profiles indicated a limited and mostly transient impact of the snus extracts, in particular on xenobiotic metabolism, while the effects of TPM were marked and sustained over time. High-confidence miRNAs that might be related to pathological conditions in vivo were identified. This study highlights the limited biological impact of Swedish snus extract on human organotypic gingival cultures.


Assuntos
Gengiva/efeitos dos fármacos , Material Particulado/análise , Extratos Vegetais/efeitos adversos , Tabaco sem Fumaça/efeitos adversos , Células Cultivadas , Gengiva/patologia , Humanos , Inflamação/genética , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Nicotina/análise , Extratos Vegetais/análise , Extratos Vegetais/química , Suécia , Fatores de Tempo , Tabaco sem Fumaça/análise , Transcriptoma/efeitos dos fármacos
3.
Nicotine Tob Res ; 21(8): 1045-1050, 2019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-29889248

RESUMO

INTRODUCTION: The Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study demonstrated that ß-carotene supplementation increases lung cancer incidence in smokers. Further, cigarettes with higher tar and nicotine content are associated with a higher risk of lung cancer. However, no studies have examined whether the increased risk associated with ß-carotene supplementation in smokers varies by the tar or nicotine content of cigarettes. METHODS: The ATBC Study was a randomized, double-blind intervention trial conducted in southwest Finland. A total of 29 133 male smokers, aged 50-69 years, were enrolled and randomly assigned to one of four groups (α-tocopherol, ß-carotene, both, or placebo). Cox proportional hazards models were used to estimate the hazard ratio (HR) and 95% confidence intervals (CI) of lung cancer risk by ß-carotene trial assignment stratified by a priori categories of cigarette tar and nicotine content. RESULTS: The ß-carotene supplementation group had significantly higher risk of developing lung cancer in all categories of tar content (yes vs. no ß-carotene supplementation-ultralight cigarettes [≤7 mg tar]: HR = 1.31, 95% CI = 0.91 to 1.89; nonfiltered cigarettes [≥21 mg tar]: HR = 1.22, 95% CI = 0.91 to 1.64; p for interaction = .91). Similarly, there was no interaction with nicotine content (yes vs. no ß-carotene supplementation-ventilated cigarettes [≤0.8 µg nicotine]: HR = 1.23, 95% CI = 0.98 to 1.54; nonfiltered cigarettes [≥1.3 µg nicotine]: HR = 1.22, 95% CI = 0.91 to 1.64; p for interaction = .83). CONCLUSION: These findings support the conclusion that supplementation with ß-carotene increases the risk of lung cancer in smokers regardless of the tar or nicotine content of cigarettes smoked. Our data suggest that all smokers should continue to avoid ß-carotene supplementation. IMPLICATIONS: Previous studies demonstrated that ß-carotene supplementation increases risk of lung cancer in smokers. This study moves the field forward by examining the potential for modification of risk of lung cancer with different levels of tar and nicotine in cigarettes smoked, as interaction with carcinogens in these components of cigarette smoke is hypothesized to be the mechanism by which ß-carotene increases risk. Our study provides evidence that the increased risk of lung cancer in smokers who take ß-carotene supplements is not dependent upon the tar or nicotine level of cigarettes smoked and suggests that all smokers should continue to avoid ß-carotene supplementation.


Assuntos
Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/prevenção & controle , Nicotina/análise , Fumar/efeitos adversos , Alcatrões/análise , beta Caroteno/efeitos adversos , Idoso , Antioxidantes/administração & dosagem , Suplementos Nutricionais/efeitos adversos , Método Duplo-Cego , Finlândia/epidemiologia , Seguimentos , Humanos , Incidência , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Provitaminas/efeitos adversos , Fumar/tratamento farmacológico , alfa-Tocoferol/administração & dosagem , beta Caroteno/administração & dosagem
4.
Proc Natl Acad Sci U S A ; 115(46): 11742-11747, 2018 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-30373836

RESUMO

Chemical analysis of residues contained in the matrix of stone smoking pipes reveal a substantial direct biomolecular record of ancient tobacco (Nicotiana) smoking practices in the North American interior northwest (Plateau), in an area where tobacco was often portrayed as a Euro-American-introduced postcontact trade commodity. Nicotine, a stimulant alkaloid and biomarker for tobacco, was identified via ultra-performance liquid chromatography-mass spectrometry in 8 of 12 analyzed pipes and pipe fragments from five sites in the Columbia River Basin, southeastern Washington State. The specimens date from 1200 cal BP to historic times, confirming the deep time continuity of intoxicant use and indigenous smoking practices in northwestern North America. The results indicate that hunting and gathering communities in the region, including ancestral Nez Perce peoples, established a tobacco smoking complex of wild (indigenous) tobacco well before the main domesticated tobacco (Nicotiana tabacum) was introduced by contact-era fur traders and settlers after the 1790s. This is the longest continuous biomolecular record of ancient tobacco smoking from a single region anywhere in the world-initially during an era of pithouse development, through the late precontact equestrian era, and into the historic period. This contradicts some ethnohistorical data indicating that kinnikinnick, or bearberry (Arctostaphylos uva-ursi) was the primary precontact smoke plant in the study area. Early use likely involved the management and cultivation of indigenous tobaccos (Nicotiana quadrivalvis or Nicotiana attenuata), species that are today exceedingly rare in the region and seem to have been abandoned as smoke plants after the entry of trade tobacco.


Assuntos
Arqueologia/métodos , Fumar Tabaco/história , Indígena Americano ou Nativo do Alasca/genética , Cromatografia Gasosa-Espectrometria de Massas/métodos , História Antiga , Humanos , Indígenas Norte-Americanos/história , Nicotina/análise , América do Norte , Nicotiana/genética , Nicotiana/metabolismo , Estados Unidos
5.
PLoS One ; 13(4): e0195422, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29630638

RESUMO

Endogenous nicotine was confirmed to be present in tea plants (Camellia sinensis L.) by liquid chromatography-tandem mass spectrometry of tea samples from tea-producing regions in six Asian countries. All samples contained nicotine (0.011-0.694 µg g-1 dry weight). Nicotine contents remained constant during manufacturing of green, oolong and black teas, implying that nicotine is stable against heating, drying, enzymatic oxidation and mechanical damage during processing. Flower buds and seeds of cultivar Yabukita also contained nicotine (0.030-0.041 µg g-1 dry weight). A comparison of two cultivars revealed that higher nicotine contents were found in the black tea cultivar Benifuki. All plant parts of hydroponic Yabukita contained nicotine (0.003-0.013 µg g-1 dry weight). Tea cells cultured in B5 medium as well as roots and stems of tea seedlings contained nicotine levels similar to those of new leaves from field-grown plants. Although the levels of endogenous nicotine in tea plants are extremely low and sample contamination cannot be discounted, these levels exceed the maximum acceptable limit in Japan (0.01 µg g-1 dry weight).


Assuntos
Camellia sinensis/metabolismo , Contaminação de Alimentos/análise , Nicotina/análise , Nicotina/biossíntese , Camellia sinensis/crescimento & desenvolvimento , Células Cultivadas , Cromatografia Líquida , Humanos , Japão , Folhas de Planta/química , Folhas de Planta/metabolismo , Espectrometria de Massas em Tandem , Chá/química
6.
Regul Toxicol Pharmacol ; 93: 92-104, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29080852

RESUMO

This series of nine papers described the operation and pre-clinical assessment of a tobacco heating product THP1.0. This last paper contextualises the pre-clinical assessment data on THP1.0 with data from other next generation products relative to cigarette smoke. The tobacco and nicotine risk continuum is a concept that ranks products according to their potential harm, with cigarettes at the highest risk extreme and Nicotine Replacement Therapy at the least risky extreme. Data generated in pre-clinical studies on THP1.0 and a range of Next Generation Products (NGPs) may provide some initial indication of potential ranking of these products, although importantly, data from such studies are limited and cannot take into consideration several important aspects for risk such as long term product use patterns. In each of the studies, the responses to the emissions from THP1.0 were substantially reduced relative to cigarette smoke. Additionally, responses from THP1.0 were very similar to those from the other NGP emissions. A comparison of the results clearly showed the emissions from all the NGPs were considerably lower than those from cigarettes and all in around the same emissions level. These results show that THP1.0 could have the potential to be a reduced risk product compared to cigarettes, though further studies assessing the exposure, individual and population risk reduction profile would be required to substantiate this potential.


Assuntos
Aerossóis/análise , Sistemas Eletrônicos de Liberação de Nicotina/métodos , Calefação/métodos , Nicotina/análise , Produtos do Tabaco/análise , Aerossóis/administração & dosagem , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Mutagênese/efeitos dos fármacos , Mutagênese/fisiologia , Nicotina/administração & dosagem
7.
Ann Intern Med ; 166(6): 390-400, 2017 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-28166548

RESUMO

BACKGROUND: Given the rapid increase in the popularity of e-cigarettes and the paucity of associated longitudinal health-related data, the need to assess the potential risks of long-term use is essential. OBJECTIVE: To compare exposure to nicotine, tobacco-related carcinogens, and toxins among smokers of combustible cigarettes only, former smokers with long-term e-cigarette use only, former smokers with long-term nicotine replacement therapy (NRT) use only, long-term dual users of both combustible cigarettes and e-cigarettes, and long-term users of both combustible cigarettes and NRT. DESIGN: Cross-sectional study. SETTING: United Kingdom. PARTICIPANTS: The following 5 groups were purposively recruited: combustible cigarette-only users, former smokers with long-term (≥6 months) e-cigarette-only or NRT-only use, and long-term dual combustible cigarette-e-cigarette or combustible cigarette-NRT users (n = 36 to 37 per group; total n = 181). MEASUREMENTS: Sociodemographic and smoking characteristics were assessed. Participants provided urine and saliva samples and were analyzed for biomarkers of nicotine, tobacco-specific N-nitrosamines (TSNAs), and volatile organic compounds (VOCs). RESULTS: After confounders were controlled for, no clear between-group differences in salivary or urinary biomarkers of nicotine intake were found. The e-cigarette-only and NRT-only users had significantly lower metabolite levels for TSNAs (including the carcinogenic metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol [NNAL]) and VOCs (including metabolites of the toxins acrolein; acrylamide; acrylonitrile; 1,3-butadiene; and ethylene oxide) than combustible cigarette-only, dual combustible cigarette-e-cigarette, or dual combustible cigarette-NRT users. The e-cigarette-only users had significantly lower NNAL levels than all other groups. Combustible cigarette-only, dual combustible cigarette-NRT, and dual combustible cigarette-e-cigarette users had largely similar levels of TSNA and VOC metabolites. LIMITATION: Cross-sectional design with self-selected sample. CONCLUSION: Former smokers with long-term e-cigarette-only or NRT-only use may obtain roughly similar levels of nicotine compared with smokers of combustible cigarettes only, but results varied. Long-term NRT-only and e-cigarette-only use, but not dual use of NRTs or e-cigarettes with combustible cigarettes, is associated with substantially reduced levels of measured carcinogens and toxins relative to smoking only combustible cigarettes. PRIMARY FUNDING SOURCE: Cancer Research UK.


Assuntos
Carcinógenos/análise , Sistemas Eletrônicos de Liberação de Nicotina/efeitos adversos , Nicotina/análise , Dispositivos para o Abandono do Uso de Tabaco/efeitos adversos , Adulto , Biomarcadores/análise , Biomarcadores/urina , Estudos Transversais , Feminino , Humanos , Masculino , Nicotina/urina , Nitrosaminas/análise , Nitrosaminas/urina , Salvia/química , Abandono do Hábito de Fumar/métodos , Fatores de Tempo , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/urina
8.
Anal Sci ; 31(8): 823-30, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26256607

RESUMO

A reliable and cost-effective method for the determination of multiple neonicotinoids was developed using a modified QuEChERS-based extraction procedure in complex matrices, namely Hedyotis diffusa (a representative of the Traditional Chinese herb which contains lots of pigment, saponin and terpene) and Semifluid extract of deer foetus (a representative of the Chinese traditional patent medicine that was produced with several different herbs, and especially containing lots of protein, except for other interference components). Ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was used for the quantification and confirmation of five compounds. Except for two transitions obtained by the MRM mode, identification was further carried out by the ion radios. The proposed chemical structure of every selected product ion and the proposed pyrolysis way were presented. The extraction, clean-up, UPLC separation and MS/MS parameters were especially optimized in order to obtain better recoveries. The low limits of detection (LODs) of five insecticides ranged from 0.04 to 0.81 µg kg(-1). Matrix matched calibration in the concentration range of 0.05 - 50 µg kg(-1) were used to compensate the matrix effect, and reasonable recoveries 80.2 - 105.4% of five compounds were demonstrated in different spiked levels with inter-RSD from 1.7 to 10.6%. The proposed method is an alternative approach to make an analysis of neonicotinoids in Chinese medicine, which is more reliable and promising compared with other detection methods.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Inseticidas/análise , Nicotina/análise , Resíduos de Praguicidas/análise , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Hedyotis/química , Inseticidas/química , Inseticidas/isolamento & purificação , Limite de Detecção , Nicotina/química , Nicotina/isolamento & purificação , Resíduos de Praguicidas/química , Resíduos de Praguicidas/isolamento & purificação , Água/química
9.
Int J Environ Res Public Health ; 12(4): 3439-52, 2015 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-25811768

RESUMO

BACKGROUND: Some electronic cigarette (EC) liquids of tobacco flavour contain extracts of cured tobacco leaves produced by a process of solvent extraction and steeping. These are commonly called Natural Extract of Tobacco (NET) liquids. The purpose of the study was to evaluate nicotine levels and the presence of tobacco-derived toxins in tobacco-flavoured conventional and NET liquids. METHODS: Twenty-one samples (10 conventional and 11 NET liquids) were obtained from the US and Greek market. Nicotine levels were measured and compared with labelled values. The levels of tobacco-derived chemicals were compared with literature data on tobacco products. RESULTS: Twelve samples had nicotine levels within 10% of the labelled value. Inconsistency ranged from -21% to 22.1%, with no difference observed between conventional and NET liquids. Tobacco-specific nitrosamines (TSNAs) were present in all samples at ng/mL levels. Nitrates were present almost exclusively in NET liquids. Acetaldehyde was present predominantly in conventional liquids while formaldehyde was detected in almost all EC liquids at trace levels. Phenols were present in trace amounts, mostly in NET liquids. Total TSNAs and nitrate, which are derived from the tobacco plant, were present at levels 200-300 times lower in 1 mL of NET liquids compared to 1 gram of tobacco products. CONCLUSIONS: NET liquids contained higher levels of phenols and nitrates, but lower levels of acetaldehyde compared to conventional EC liquids. The lower levels of tobacco-derived toxins found in NET liquids compared to tobacco products indicate that the extraction process used to make these products did not transfer a significant amount of toxins to the NET. Overall, all EC liquids contained far lower (by 2-3 orders of magnitude) levels of the tobacco-derived toxins compared to tobacco products.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Nicotiana/química , Nicotina/análise , Extratos Vegetais/análise , Acetaldeído/análise , Formaldeído/análise , Nitratos/análise , Nitrosaminas/análise , Fenóis/análise , Nicotiana/toxicidade
10.
Toxicol In Vitro ; 27(2): 932-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23318728

RESUMO

Cigarette smoking is a leading cause of cardiovascular disease. The cardiovascular effects of smoking are probably multifactorial, including effects on platelets. Previous reports investigating the effects of nicotine and tobacco on platelet function are inconsistent. The present study investigated in vitro effects of nicotine, its major metabolites, tobacco extracts and extract of tobacco-free snuff on human platelets. None of the metabolites cotinine, cotinine-N-oxide, nicotine-1'-N-oxide or trans-3'-hydroxycotinine (0.1-10 µM) affected platelet aggregation or P-selectin expression. Nicotine (10 µM) weakly increased platelet aggregation, whereas trans-3'-hydroxycotinine (0.1 µM) and nicotine-1'-N-oxide (1-10 µM) weakly inhibited adhesion to fibrinogen. To elucidate the influence of other tobacco compounds, we investigated the impact of moist tobacco and smoke extracts on platelet function. Filtered extracts of oral snuff, cigarette smoke and tobacco free snuff inhibited platelet adhesion concentration-dependently. The inhibitory effects of tobacco extracts on platelet adhesion were independent of nicotine content and the nitric-oxide-pathway and not mediated through a platelet-nicotine-receptor. Taken together, tobacco extracts inhibit platelet activation during short-term in vitro challenge. As only limited effects of nicotine and nicotine metabolites were seen, the tobacco-induced platelet inhibition are likely induced by other compounds present in tobacco and tobacco free snuff.


Assuntos
Plaquetas/efeitos dos fármacos , Cotinina/análogos & derivados , Cotinina/toxicidade , Nicotiana , Extratos Vegetais/toxicidade , Plaquetas/fisiologia , Células Cultivadas , Humanos , Nicotina/análise , Nicotina/toxicidade , Extratos Vegetais/química , Agregação Plaquetária/efeitos dos fármacos
11.
Ying Yong Sheng Tai Xue Bao ; 22(5): 1189-94, 2011 May.
Artigo em Chinês | MEDLINE | ID: mdl-21812293

RESUMO

An orthogonal regression field experiment was conducted to study the effects of combined fertilization of N, P, and K on the nicotine content in the upper leaves of filling type flue-cured tobacco (Nicotiana tobacum) variety "Longjiang 911" from Northeast China. The regression effect models of N, P, and K fertilization rates and upper leaf nicotine content were established, and the effects of the fertilization rates and their interactions were analyzed. Based on these, an optimized NPK fertilization scheme was drawn up to reduce the nicotine content in the upper leaves of "Longjiang 911". The model analyses showed that the nicotine content in the upper leaves of "Longjiang 911" decreased after an initial increase with the increasing fertilization rate of N, increased with the increasing fertilization rate of P, and had a sharp decrease with the increasing fertilization rate of K. The two-factor effects of NKP on the nicotine content were in the order of NK >PK>NP. Within a certain range of fertilization rates, NP and PK had negative correlations with the nicotine content, suggesting the antagonistic effects between N and P and between P and K, while NK was on the contrary, suggesting the synergistic effects between N and K. A comprehensive analysis on the regression effect models of N, P, and K fertilization rates and upper leaf nicotine content showed that the basal fertilization rates of N, P, and K for the tobacco production on warp soil were recommended as 33.5-47.8 kg x hm(-2), 40.2-63.6 kg x hm(-2), and 78.0-119.6 kg x hm(-2), respectively.


Assuntos
Fertilizantes , Nicotiana/química , Nicotina/análise , Fósforo/farmacologia , Potássio/farmacologia , Sódio/farmacologia , Agricultura/métodos , Simulação por Computador , Análise de Regressão , Nicotiana/crescimento & desenvolvimento
12.
J Pharm Biomed Anal ; 55(5): 964-71, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21497036

RESUMO

Nicotine is considered to be a specific substrate for UGT2B10, an isoform of human uridine diphosphate glucuronosyltransferase (UGT). In the present study, a sensitive and selective liquid chromatography/tandem mass spectrometry (LC-MS-MS) method for quantification of nicotine N-glucuronide in pooled human liver microsomal incubates was developed and validated. Proteins in a 200µL aliquot of incubation solution were precipitated by adding 40µL 35% perchloric acid. The overall extraction efficiency was greater than 98%. Nicotine N-glucuronide and internal standard were recorded using selected reaction monitoring in positive ion electrospray with ion transitions of m/z 339-163 and m/z 342-166, respectively. The linear calibration curve was obtained over the concentration range of 10-1000nM, with a lower limit of quantification of 10nM. The intra-day and inter-day precision (% CV) and accuracy (% bias) of the method were within 15% at all quality control levels. Nicotine glucuronide in processed samples was stable for 24h at room temperature and 48h at 4°C based on the stability experiments performed in this study. This established method was employed to evaluate the inhibitory effects of five target compounds including amitriptyline, hecogenin, imipramine, lamotrigine, and trifluoperazine on enzymatic activity of UGT2B10. IC(50) values for inhibition of nicotine N-glucuronidation by amitriptyline, imipramine, lamotrigine, and trifluoperazine were calculated. Trifluoperazine was found to be a non-substrate inhibitor for human UGT2B10.


Assuntos
Cromatografia Líquida/métodos , Glucuronatos/análise , Glucuronosiltransferase/antagonistas & inibidores , Nicotina/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Amitriptilina/análise , Calibragem , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Imipramina/análise , Concentração Inibidora 50 , Cinética , Microssomos Hepáticos/efeitos dos fármacos , Nicotina/análise , Nicotina/química , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray/métodos , Temperatura , Trifluoperazina/análise
13.
Analyst ; 136(8): 1566-8, 2011 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-21331396

RESUMO

Advances with para-hydrogen induced polarization open up new fields of applications for portable low-field NMR. Here we report the possibility of tracing drugs down to the micromolar regime. We could selectively polarize nicotine quantities similar to those found in one cigarette. Also less than 1 mg of harmine, a drug used for treatment of Parkinson's disease, and morphine extracted from an opium solution were detectable after polarization with para-hydrogen in single-scan (1)H-experiments. Moreover, we demonstrate the possibility to selectively enhance and detect the (1)H-signal of drug molecules with PHIP in proton rich standard solutions that would otherwise mask the (1)H NMR signal of the drug.


Assuntos
Resíduos de Drogas/análise , Espectroscopia de Ressonância Magnética/métodos , Harmina/análise , Hidrogênio/química , Morfina/análise , Nicotina/análise , Ópio/química , Nicotiana/química
14.
J Endocrinol ; 206(1): 55-63, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20453077

RESUMO

Maternal nicotine (NIC) exposure during lactation leads to overweight, hyperleptinemia, and hypothyroidism in adult rat offspring. In this model, we analyzed adipocyte morphology, glucose homeostasis (serum insulin and adiponectin; liver and muscle glycogen), serum lipid, and the leptin signaling pathway. After birth, osmotic minipumps were implanted in lactating rats, which were divided into the groups NIC (6 mg/kg per day s.c. for 14 days) and control (C, saline). NIC and C offspring were killed at the age of 180 days. Adult NIC rats showed higher total body fat (+10%, P<0.05), visceral fat mass (+12%, P<0.05), and cross-sectional area of adipocytes (epididymal: +12% and inguinal: +43%, P<0.05). Serum lipid profile showed no alteration except for apolipoprotein AI, which was lower. We detected a lower adiponectin:fat mass ratio (-24%, P<0.05) and higher insulinemia (+56%, P<0.05), insulin resistance index (+43%, P<0.05), leptinemia (+113%, P<0.05), and leptin:adiponectin ratio (+98%, P<0.05) in the adult NIC group. These rats presented lower hypothalamic contents of the proteins of the leptin signaling pathway (leptin receptor (OB-R): -61%, janus tyrosine kinase 2: -41%, and p-signal transducer and activator of transcription 3: -56%, P<0.05), but higher suppressor of cytokine signaling 3 (+81%, P<0.05). Therefore, NIC exposure only during lactation programs rats for adipocyte hypertrophy in adult life, as well as for leptin and insulin resistance. Through the effects of NIC, perinatal maternal cigarette smoking may be responsible for the future development of some components of the metabolic syndrome in the offspring.


Assuntos
Animais Recém-Nascidos , Hipotálamo/fisiologia , Resistência à Insulina , Lactação , Leptina/fisiologia , Nicotina/administração & dosagem , Adipócitos/patologia , Adiponectina/sangue , Animais , Glicemia/metabolismo , Cotinina/análise , Cotinina/sangue , Resistência a Medicamentos , Feminino , Glicogênio/análise , Homeostase , Hipertrofia , Insulina/sangue , Lipídeos/sangue , Fígado/química , Masculino , Leite/química , Músculo Esquelético/química , Nicotina/análise , Nicotina/sangue , Ratos , Transdução de Sinais
15.
J Chromatogr B Analyt Technol Biomed Life Sci ; 878(9-10): 725-37, 2010 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-20097626

RESUMO

A novel validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) procedure was developed and fully validated for the simultaneous determination of nicotine-N-beta-D-glucuronide, cotinine-N-oxide, trans-3-hydroxycotinine, norcotinine, trans-nicotine-1'-oxide, cotinine, nornicotine, nicotine, anatabine, anabasine and cotinine-N-beta-D-glucuronide in human plasma or urine. Target analytes and corresponding deuterated internal standards were extracted by solid-phase extraction and analyzed by LC-MS/MS with electrospray ionization (ESI) using multiple reaction monitoring (MRM) data acquisition. Calibration curves were linear over the selected concentration ranges for each analyte, with calculated coefficients of determination (R(2)) of greater than 0.99. The total extraction recovery (%) was concentration dependent and ranged between 52-88% in plasma and 51-118% in urine. The limits of quantification for all analytes in plasma and urine were 1.0 ng/mL and 2.5 ng/mL, respectively, with the exception of cotinine-N-beta-D-glucuronide, which was 50 ng/mL. Intra-day and inter-day imprecision were < or = 14% and < or = 17%, respectively. Matrix effect (%) was sufficiently minimized to < or = 19% for both matrices using the described sample preparation and extraction methods. The target analytes were stable in both matrices for at least 3 freeze-thaw cycles, 24 h at room temperature, 24 h in the refrigerator (4 degrees C) and 1 week in the freezer (-20 degrees C). Reconstituted plasma and urine extracts were stable for at least 72 h storage in the liquid chromatography autosampler at 4 degrees C. The plasma procedure has been successfully applied in the quantitative determination of selected analytes in samples collected from nicotine-abstinent human participants as part of a pharmacokinetic study investigating biomarkers of nicotine use in plasma following controlled low dose (7 mg) transdermal nicotine delivery. Nicotine, cotinine, trans-3-hydroxycotinine and trans-nicotine-1'-oxide were detected in the particular sample presented herein. The urine procedure has been used to facilitate the monitoring of unauthorized tobacco use by clinical study participants at the time of physical examination (before enrollment) and on the pharmacokinetic study day.


Assuntos
Alcaloides/análise , Cromatografia Líquida/métodos , Nicotina/análise , Nicotina/metabolismo , Extratos Vegetais/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Alcaloides/sangue , Alcaloides/metabolismo , Alcaloides/urina , Humanos , Limite de Detecção , Nicotina/sangue , Nicotina/urina , Extratos Vegetais/sangue , Extratos Vegetais/metabolismo , Extratos Vegetais/urina , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Nicotiana/química
16.
Food Chem Toxicol ; 48(2): 755-63, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20034536

RESUMO

Nicotine and flavorant compound levels were measured in 10 "mint"-related sub-brands and 8 "wintergreen" sub-brands of smokeless tobacco (SLT). Also analyzed were "mint"-related and "wintergreen" confectionery products. Of the "mint" SLT, "Timberwolf Packs Mint Pouches" contained the highest menthol level (5.3 mg/g); the average for the five most-highly mentholated SLT products was 4.3 mg/g. The average for the most five most-highly mentholated confectionery products was 3.5 mg/g. For hard candy, a reported average of maximum use levels is 2.1 mg/g (Burdock, 2009). Of the "wintergreen" SLT, "Hawken Wintergreen" was found to contain the highest methyl salicylate (MS) level (29.7 mg/g). The average of the five highest SLT MS levels was 23.8 mg/g, i.e., 5x higher than the level found in the confectionery product with the highest MS level (LifeSavers Wint O Green Sugar Free, 4.6 mg/g). For hard candy, a reported average of maximum use levels is 2.0 mg/g (Burdock, 2009). Assuming 23.8 mg/g MS in SLT, SLT use at 15 g/day, 100% bodily absorption of the MS, and 60 kg body weight, the average daily intake would be 6.0 mg/kg-day, i.e., 12x the acceptable daily intake (ADI) of 0.5 mg/kg-day established for this compound by a joint FAO/WHO committee.


Assuntos
Doces , Aromatizantes/análise , Mentha/química , Óleos Voláteis/análise , Extratos Vegetais/análise , Tabaco sem Fumaça/química , Mentol/análise , Nicotina/análise , Salicilatos/análise
17.
Chudoku Kenkyu ; 21(2): 115-22, 2008 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-18516935

RESUMO

During 2006, the Japan Poison Information Center received 2583 inquiries about ingestion of cigarette, which is the most frequent household products ingested by children in Japan. During 2001-2006, two hundred and seventy-six children under seven years of age ingesting cigarettes and its related substances presented to the emergency department in Japan Red Cross Hospital Wakayama Center. The peak age was one year and younger, so-called "ingestion age". Patients were frequently detected chewing cigarettes and the situation of cases varied individually. It was impossible to estimate the amount of ingested cigarette based on the medical interview. Eighty-three percent of the patients were asymptomatic. Treatment strategy has been changed into a noninvasive one. Gastric lavage has not been performed by emergency physicians since 2001, and by pediatricians since 2006. After the medical observation for two hours following ingestion, all the children except one (who was hospitalized because of his family's request) were discharged from the emergency department. Independent of doing gastric lavage, all the 276 children had good prognosis. We conluded that ingestion of cigarette in children is generally benign. No gastric lavage, but medical observation for two hours following ingestion in emergency department is our recommendation of management.


Assuntos
Ingestão de Alimentos , Lavagem Gástrica , Nicotiana/intoxicação , Observação , Fatores Etários , Criança , Pré-Escolar , Contraindicações , Feminino , Humanos , Lactente , Ipeca/administração & dosagem , Japão/epidemiologia , Dose Letal Mediana , Masculino , Nicotina/análise , Nicotina/sangue , Prognóstico , Fatores de Tempo , Nicotiana/química
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(9): 1751-3, 2007 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-18051521

RESUMO

The influence of sample test conditions on the NIR veracity was studied with homemade grating diffuse NIR instrument using Yunnan flue-cured tobacco. Deducing analysis error was achieved by model self-emendation when a global NIR model was set up. Without regarding the influence of loading samples and test conditions, the test repetition error, re-loading error and samples tightness error, which were brought by instrument S/N, accounted for 50%, 30% and 20% of the total error, respectively. Depressing sample could reduce errors brought by sample tightness. Changes in test conditions could bring more analysis error, which was larger than the total of repetition error. These results theoretically explain the influence of sample test conditions on the NIR analysis veracity, which can provide basic theory data for farther improvement of homemade instrument and offer a new idea for resolving this problem.


Assuntos
Nicotiana/química , Nicotina/análise , Extratos Vegetais/análise , Espectroscopia de Luz Próxima ao Infravermelho/normas , Carboidratos/análise , Controle de Qualidade , Espectroscopia de Luz Próxima ao Infravermelho/métodos
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(9): 1754-6, 2007 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-18051522

RESUMO

The influence of sample annum and the distribution of sample component on NIR veracity was studied with homemade grating diffuse NIR instrument using Yunnan flue-cured tobacco. Results showed that sample annum had an obvious influence on the total sugar and nicotine models, but had an unconspicuous influence on the total-nitrogen model. Models set up by samples, whose component content distribution was normal school, was better than those set up by even distribution. The conclusion in this study has a significant referenced value for the method and principle to select representative samples to modeling from a large amount of specimens.


Assuntos
Nicotiana/química , Nicotina/análise , Extratos Vegetais/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Carboidratos/análise , China , Controle de Qualidade , Fatores de Tempo
20.
Anal Chem ; 79(16): 6094-101, 2007 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-17628043

RESUMO

A novel plasma-assisted desorption/ionization (PADI) method that can be coupled with atmospheric pressure sampling mass spectrometry to yield mass spectral information under ambient conditions of pressure and humidity from a range of surfaces without the requirement for sample preparation or additives is reported. PADI is carried out by generating a nonthermal plasma which interacts directly with the surface of the analyte. Desorption and ionization then occur at the surface, and ions are sampled by the mass spectrometer. The PADI technique is demonstrated and compared with desorption electrospray ionization (DESI) for the detection of active ingredients in a range of over-the-counter and prescription pharmaceutical formulations, including nonsterodial anti-inflammatory drugs (mefenamic acid, Ibugel, and ibuprofen), analgesics (paracetamol, Anadin Extra), and Beecham's "all in one" cold and flu remedy. PADI has also been successfully applied to the analysis of nicotine in tobacco and thiosulfates in garlic. PADI experiments have been performed using a prototype source interfaced with a Waters Platform LCZ single-quadrupole mass spectrometer with limited modifications and a Hiden Analytical HPR-60 molecular beam mass spectrometer (MBMS). The ability of PADI to rapidly detect active ingredients in pharmaceuticals without the need for prior sample preparation, solvents, or exposed high voltages demonstrates the potential of the technique for high-throughput screening in a pharmaceutical or forensic environment.


Assuntos
Pressão Atmosférica , Preparações Farmacêuticas/análise , Analgésicos/análise , Anti-Inflamatórios não Esteroides/análise , Alho/química , Umidade , Nicotina/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Propriedades de Superfície , Tiossulfatos/análise
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