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1.
Nicotine Tob Res ; 20(4): 458-465, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-28482017

RESUMO

Introduction: Novel nicotine delivery systems represent an evolving part of the tobacco harm reduction strategy. The pharmacokinetic (PK) profile of nicotine delivered by P3L, a pulmonary nicotine delivery system, and its effects on smoking urges and craving relief in relation to Nicorette inhalator were evaluated. Methods: This open-label, ascending nicotine levels study was conducted in 16 healthy smokers. Three different nicotine delivery levels, 50, 80, and 150 µg/puff, delivered by the P3L system were evaluated consecutively on different days after the use of the Nicorette inhalator. Venous nicotine PK, subjective effects, and tolerability were assessed. Results: Geometric least-squares means for maximum plasma nicotine concentration (Cmax), generated by the mixed-effect model for exposure comparison, were 9.7, 11.2, and 9.8 ng/mL for the 50, 80, and 150 µg/puff P3L variants, respectively, compared to 6.1 ng/mL after Nicorette inhalator use. Median time from product use start to Cmax was 7.0 minutes for all P3L, compared to 30.0 minutes for the Nicorette inhalator. Craving reduction was slightly faster than with the Nicorette inhalator as assessed with the visual analog scale craving score. The mean Questionnaire of Smoking Urges -brief total scores did not differ for both products. P3L was well tolerated. Conclusions: At all three nicotine levels tested, the inhalation of the nicotine lactate aerosol delivered with the P3L provided plasma nicotine concentrations higher and faster compared to the Nicorette inhalator. The plasma nicotine concentration-time profile supports a pulmonary route of absorption for P3L compared to the oromucosal absorption of the Nicorette inhalator. Implications: The combination of nicotine and lactic acid with the P3L device shows potential over existing nicotine delivery systems by delivering nicotine with kinetics close to published data on conventional cigarettes and without exogenous carrier substances as used in current electronic nicotine delivery systems. Altogether, the PK profile, subjective effects, and safety profile obtained in this study suggest P3L is an innovative nicotine delivery product that will be acceptable to adult smokers as an alternative to cigarettes.


Assuntos
Fissura , Sistemas Eletrônicos de Liberação de Nicotina/métodos , Nicotina/administração & dosagem , Nicotina/sangue , Fumar Tabaco/sangue , Administração por Inalação , Adulto , Estudos Cross-Over , Feminino , Humanos , Masculino , Fumantes/psicologia , Abandono do Hábito de Fumar/psicologia , Inquéritos e Questionários , Fumar Tabaco/tendências , Adulto Jovem
2.
Nat Prod Commun ; 7(1): 113-6, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22428262

RESUMO

The chemical composition of the hydrodistilled leaf essential oil from Pulicaria stephanocarpa Balf. Fil was determined by GC-MS analysis, and its antimicrobial, antioxidant and anticholinesterase (AChE) activities were evaluated. Eighty-three compounds were identified representing 97.2% of the total oil. (E)-Caryophyllene 13.4%, (E)-nerolidol 8.5%, caryophyllene oxide 8.5%, alpha-cadinol 8.2% spathulenol 6.8% and tau-cadinol 4.7%, were the main components. Antimicrobial activity of the oil, evaluated using the disc diffusion and broth dilution methods, demonstrated the highest susceptibility on Gram-positive bacteria and Candida albicans. The free radical scavenging ability of the oil was assessed by the DPPH assay to show antiradical activity with IC50 of 330 microg/mL. Moreover, the oil revealed an AChE inhibitory activity of 47% at a concentration of 200 microg/mL using Ellman's method.


Assuntos
Anti-Infecciosos/farmacologia , Inibidores da Colinesterase/farmacologia , Sequestradores de Radicais Livres/farmacologia , Óleos Voláteis/análise , Óleos Voláteis/farmacologia , Pulicaria/química , Cromatografia Gasosa-Espectrometria de Massas
3.
Artigo em Inglês | MEDLINE | ID: mdl-22468008

RESUMO

A total of 30 chloroform and methanol extracts from the following endemic Soqotran plants Acridocarpus socotranus Olive, Boswellia socotranao Balf.fil, Boswellia elongata Balf. fil., Caralluma socotrana N. Br, Cephalocroton socotranus Balf.f, Croton socotranus Balf. fil.., Dendrosicycos socotrana Balf.f., Dorstenia gigas Schweinf. ex Balf. fil., Eureiandra balfourii Cogn. & Balf. fil., Kalanchoe farinaceae Balf.f, Limonium sokotranum (Vierh) Radcl. Sm), Oldenlandia pulvinata, Pulicaria diversifolia (Balf. and Pulicaria stephanocarpa Balf. were screened for their acetylcholinesterase inhibitory activity by using in vitro Ellman method at 50 and 200 µg/ml concentrations. Chloroform extracts of Croton socotranus, Boswellia socotrana, Dorstenia gigas, and Pulicaria stephanocarpa as well as methanol extracts of Eureiandra balfourii exhibited inhibitory activities higher than 50 % at concentration of 200 µg. At a concentrations of 50 µg, the chloroform extract of Croton socotranus exhibited an inhibition of 40.6 %.


Assuntos
Inibidores da Colinesterase/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Clorofórmio , Inibidores da Colinesterase/química , Etnofarmacologia , Ilhas do Oceano Índico , Metanol , Testes de Sensibilidade Microbiana , Extratos Vegetais/química
4.
J Agric Food Chem ; 57(20): 9607-12, 2009 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-19778058

RESUMO

Infections with Phytophthora infestans, the causal agent of potato and tomato late blight disease, are difficult to control and can lead to considerable agricultural losses. Thus, the development of new effective agents against the pathogen is of great interest. In previous work, (E)-4-oxohexadec-2-enoic acid (3) was isolated from Hygrophorus eburneus, which exhibited fungicidal activity against Cladosporium cucumerinum. Here, the inhibitory effect of 3 on P. infestans spore germination and mycelium growth in vitro is demonstrated. The in vivo effect on infections of whole potato plants was investigated by spraying plants with the sodium salt of 3, sodium (2E)-4-oxohexadec-2-enoic acid (4), prior to P. infestans inoculation. Additionally, the influence of 3 on mycelium growth of Colletotrichum coccodes, the causal agent of potato black dot disease, was analyzed. In all approaches, a significant inhibition of pathogen development was achieved. Importantly, the unsaturated fatty acid exerted no toxic effect when sprayed on plants, a prerequisite for its commercial use.


Assuntos
Ácidos Graxos Insaturados/farmacologia , Fungicidas Industriais/farmacologia , Phytophthora infestans/efeitos dos fármacos , Colletotrichum/efeitos dos fármacos , Phytophthora infestans/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Solanum tuberosum/microbiologia , Esporos Fúngicos/efeitos dos fármacos , Esporos Fúngicos/crescimento & desenvolvimento
5.
J Nat Prod ; 71(6): 1092-4, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18447384

RESUMO

Chemical analysis of the fruiting bodies of the agaricoid fungus Cortinarius subtortus yielded three new natural products, two quinoline and one isocarbostyryl alkaloid. The structures of compounds 1- 3 were determined by analysis of NMR and MS data. Compound 1 exhibited inhibitory effects against the phytopathogenic fungus Colletotrichum coccodes. All three compounds displayed moderate antioxidant activity in a DPPH free radical scavenging bioassay.


Assuntos
Agaricales/química , Alcaloides/isolamento & purificação , Antifúngicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Colletotrichum/efeitos dos fármacos , Sequestradores de Radicais Livres/isolamento & purificação , Isoquinolinas/isolamento & purificação , Alcaloides/química , Alcaloides/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Compostos de Bifenilo , Colletotrichum/crescimento & desenvolvimento , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Carpóforos/química , Alemanha , Isoquinolinas/química , Isoquinolinas/farmacologia , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Picratos/farmacologia
6.
Phytochem Anal ; 19(4): 335-41, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18401852

RESUMO

The beta-carboline alkaloids harmane (1) and norharmane (2) were isolated from fruiting bodies of Hygrophorus eburneus (Bull.) Fr. as well as brunnein A (3) from Hygrophorus hyacinthinus Quél. (Tricholomataceae, Agaricales) for the first time. Their occurrence within the genus was investigated using liquid chromatography/electrospray ionisation tandem mass spectrometric methods, especially by selected reaction monitoring. Based on these results their chemotaxonomical relevance is discussed.


Assuntos
Agaricales/química , Alcaloides/análise , Carbolinas/análise , Cromatografia Líquida/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
7.
Chem Biodivers ; 5(4): 664-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18421759

RESUMO

Two new N-glucosylated indole alkaloids were isolated from fruiting bodies of the basidiomycete Cortinarius brunneus (Pers.) Fr. The structures were elucidated by means of the spectroscopic data. Additionally, the very recently reported compounds N-1-beta-glucopyranosyl-3-(carboxymethyl)-1H-indole (3) and N-1-beta-glucopyranosyl-3-(2-methoxy-2-oxoethyl)-1H-indole (4) could be detected. Compound 3 is the N-glucoside of the plant-growth regulator 1H-indole-3-acetic acid (IAA), but, in contrast, it does not exhibit auxin-like activity in an Arabidopsis thaliana tap root elongation assay.


Assuntos
Agaricales/química , Glucosídeos/isolamento & purificação , Alcaloides Indólicos/isolamento & purificação , Arabidopsis , Glucosídeos/química , Glucosídeos/farmacologia , Alcaloides Indólicos/química , Alcaloides Indólicos/farmacologia , Ácidos Indolacéticos/farmacologia , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/efeitos dos fármacos
8.
J Nat Prod ; 70(9): 1529-31, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17854153

RESUMO

Four beta-carboline alkaloids, brunneins A-C (1-3) and 3-(7-hydroxy-9H-beta-carboline-1-yl)propanoic acid (4), were isolated from fruiting bodies of the agaricoid fungus Cortinarius brunneus. The structures of 1-3 were determined by analysis of NMR and MS data, and the structure of compound 4 was determined by comparison with published data. Brunnein A (1) exhibited very low cholinesterase inhibitory effects and no cytotoxicity.


Assuntos
Agaricales/química , Alcaloides/isolamento & purificação , Carbolinas/isolamento & purificação , Inibidores da Colinesterase/isolamento & purificação , Alcaloides/química , Alcaloides/farmacologia , Animais , Carbolinas/química , Carbolinas/farmacologia , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Alemanha , Humanos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular
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