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1.
Regul Toxicol Pharmacol ; 61(2): 199-209, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21821091

RESUMEN

Cigarillos (aka little cigars) have been increasing in popularity unlike cigarettes; but relatively little is known about the toxicology of the mainstream smoke (MSS) from such products. Therefore, the objective of this work was to compare the toxicological properties of the MSS (Health Canada Intensive smoking conditions) from a range of cigarillo products with the toxicological properties of MSS of cigarettes. Three in vitro assays were used to evaluate the toxicities of the MSS total particulate matter (TPM): (1) mutagenicity using Ames assay with Salmonella strains TA98 and TA100 with S9 metabolic activation (+S9); (2) cytotoxicity using the Neutral Red Uptake (NRU) assay with CHO (Chinese Hamster Ovary) cells; and (3) genotoxicity using the micronucleus assay with CHO cells and short-term exposures (3-h ± S9). The Ames assay (TA100+S9) and the NRU assay were also applied to the gas/vapour phase of the MSS that passed through the Cambridge pad. On a per-milligram-nicotine basis, the preferred way of comparing toxicities of different types of tobacco products, the MSS from cigarillos was not less toxic, and in some cases more toxic (TPM fraction TA98+S9, NRU), than the MSS from cigarettes. Thus, our findings support our prior work on smoke mutagenicity that showed MSS from cigarillos was not less toxic than MSS from cigarettes.


Asunto(s)
Mutágenos/análisis , Nicotiana/química , Nicotina/análisis , Humo/análisis , Fumar/efectos adversos , Animales , Células CHO , Canadá , Cricetinae , Humanos , Pruebas de Micronúcleos/métodos , Pruebas de Mutagenicidad/métodos , Mutágenos/envenenamiento , Mutágenos/toxicidad , Rojo Neutro/análisis , Rojo Neutro/envenenamiento , Rojo Neutro/toxicidad , Nicotina/envenenamiento , Nicotina/toxicidad , Material Particulado/análisis , Material Particulado/envenenamiento , Material Particulado/toxicidad , Salmonella/efectos de los fármacos
2.
Regul Toxicol Pharmacol ; 53(2): 121-33, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19135498

RESUMEN

Some health experts are recommending that smokers who refuse to quit or refuse to use nicotine replacement therapy (NRT) such as nicotine-containing chewing gum switch to certain types of smokeless tobacco products (STP) such as Swedish snus. Other health experts disagree citing the uncertainty in the composition of commercially available STP, the lack of governmental regulations to ensure that STP advertised to meet certain standards (i.e., GothiaTek) do actually meet such standards, and the uncertainty that any STP can provide as safe as alternative to smoking as NRT. One reason for uncertainty is the dearth of detailed chemical and toxicological information on contemporary STP. Unlike the situation with cigarettes, there are few standardized methods for analytical and toxicological studies of STP. Consequently, the objective for this work was to characterize several types of STP available on the Canadian market using the modifications of the Official Health Canada chemical and toxicological methods developed for cigarettes. Moist snuff samples tested had TSNA and B[a]P levels somewhat above the GothiaTek standard while samples of Swedish snus, low-moisture snuff, and US-style chewing tobacco did not. Use of in vitro assays to assess STP toxicity was of limited utility in distinguishing product types.


Asunto(s)
Tabaquismo/etiología , Tabaco sin Humo/normas , Pruebas de Toxicidad/métodos , Publicidad , Animales , Benzo(a)pireno/química , Canadá , Regulación Gubernamental , Humanos , Técnicas In Vitro , Nitrosaminas/química , Ratas , Tabaco sin Humo/química , Tabaco sin Humo/toxicidad
3.
J Agric Food Chem ; 49(1): 142-5, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11305251

RESUMEN

The methanolic extract of Apium graveolens seeds was investigated for bioactive compounds and resulted in the isolation and characterization of mosquitocidal, nematicidal, and antifungal compounds sedanolide (1), senkyunolide-N (2), and senkyunolide-J (3). Their structures were determined by 1H and 13C NMR spectral methods. Compounds 1-3 gave 100% mortality at 25, 100, and 100 microg mL(-1), respectively, on the nematode, Panagrellus redivivus. Compound 1 showed 100% mortality at 50 microg mL(-1) on nematode, Caenorhabditis elegans, and fourth-instar mosquito larvae, Aedes aegyptii. Also, it inhibited the growth of Candida albicans and Candida parapsilasis at 100 microg mL(-1). Compounds 2 and 3 were isolated for the first time from A. graveolens. This is the first report of the mosquitocidal, nematicidal, and antifungal activities of compounds 1-3.


Asunto(s)
Antifúngicos/aislamiento & purificación , Antinematodos/aislamiento & purificación , Apiaceae , Insecticidas/aislamiento & purificación , Semillas/química , Aedes/efectos de los fármacos , Animales , Antifúngicos/química , Antifúngicos/farmacología , Antinematodos/química , Antinematodos/farmacología , Benzofuranos/química , Benzofuranos/aislamiento & purificación , Benzofuranos/farmacología , Caenorhabditis elegans/efectos de los fármacos , Candida/efectos de los fármacos , Candida/crecimiento & desarrollo , Insecticidas/química , Insecticidas/farmacología , Metanol , Nematodos/efectos de los fármacos , Extractos Vegetales/química
4.
J Agric Food Chem ; 48(9): 3785-8, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10995271

RESUMEN

Bioassay-directed isolation and purification of the hexane extract of Apium graveolens L. seeds led to the characterization of three compounds: beta-selinene (1), 3-n-butyl-4,5-dihydrophthalide (2) and 5-allyl-2-methoxyphenol (3). The structures of these compounds were established by using (1)H and (13)C NMR spectral methods. Compounds, 1-3 demonstrated 100% mortality on fourth-instar Aedes aegyptii larvae at 50, 25, and 200 microg mL(-)(1), respectively, in 24 h. Also, 2 inhibited the growth of Candida albicans and Candida kruseii at 100 microg mL(-)(1). It inhibited both topoisomerase-I and -II enzyme activities at 100 microg mL(-)(1). Compound 2 displayed 100% mortality at 12.5 and 50 microg mL(-)(1), respectively, when tested on nematodes, Panagrellus redivivus and Caenorhabditis elegans. The triglyceride, 1,3-di[(cis)-9-octadecenoyl]-2-[(cis,cis)-9, 12-octadecadienoyl]glycerol (4) and 3 were isolated for the first time from A. graveolens seeds, although 4 was not biologically active.


Asunto(s)
Apiaceae/química , Semillas/química , Triglicéridos/aislamiento & purificación , Apiaceae/embriología , Humanos , Espectroscopía de Resonancia Magnética , Triglicéridos/química
5.
Regul Toxicol Pharmacol ; 48(3): 320-30, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17614170

RESUMEN

Toxicological data are an important aspect of tobacco product characterization. In this study, TPM (Total Particulate Matter) (three replicates) was collected from cigarettes [five brands, ISO conditions: puff volume, 35 mL; duration, 2s; interval, 60s (35/2/60)], cigars (two brands, 45/2/30), cigarillos (two brands, 35/2/60), bidis (two brands, 45/2/30), and pipe tobacco (two brands, 50/2/12). TPM was extracted from the Cambridge filter pad using dimethyl sulfoxide (DMSO). Smokeless tobacco (ST) (six brands) was extracted with DMSO using an ultrasonic homogenizer. Both types of extracts were filtered and stored at -80 degrees C. All extracts were analyzed for humectants, water and nicotine. Mutagenic activity was assessed per OECD guideline 471 using Salmonella typhimurium TA98+S9 and TA100+S9. TA98+S9 response (specific activity expressed as revertants/mg nicotine) was greatest for the cigarette fabricated with dark, air-cured tobaccos. Average product responses with TA98+S9 based on nicotine and relative to cigarettes (excluding dark tobacco) were cigars, 242%; cigarillos, 238%; bidis, 91%; and pipe tobacco, 44%. ST response was not significant for TA98+S9. Corresponding values for TA100+S9 were cigars, 189%; cigarillos, 155%; pipe tobacco, 130%; bidis, 114% and ST, 34%. ST TA100+S9 response ranged from a low of 501 to a high of 8547 revertants/mg nicotine, depending on ST composition.


Asunto(s)
Pruebas de Mutagenicidad , Mutágenos , Nicotiana/toxicidad , Extractos Vegetales/toxicidad , Relación Dosis-Respuesta a Droga , Nicotina/química , Material Particulado , Extractos Vegetales/química , Plantas Tóxicas/química , Salmonella typhimurium/efectos de los fármacos , Nicotiana/química , Tabaco sin Humo/química , Tabaco sin Humo/toxicidad
6.
Phytomedicine ; 9(4): 312-8, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12120812

RESUMEN

Cyclooxygenase inhibitory and antioxidant bioassay-directed extraction and purification of celery seeds yielded sedanolide (1), senkyunolide-N (2), senkyunolide-J (3), 3-hydroxymethyl-6-methoxy-2,3-dihydro-1H-indol-2-ol (4), L-tryptophan (6), and 7-[3-(3,4-dihydroxy-4-hydroxymethyl-tetrahydro-furan-2-yloxy)-4,5-dihydroxy-6-hydroxymethyl-tetrahydro-pyran-2-yloxy]-5-hydroxy-2-(4-hydroxy-3-methoxy-phenyl)-chromen-4-one (7). The structures of compounds 1-7 were determined using spectroscopic methods. Compound 4 is reported here for the first time. At 250 pg ml(-1), compounds 1-4, 6 and 7 displayed prostaglandin H endoperoxide synthase-I (COX-I) and prostaglandin H endoperoxide synthase-II (COX-II) inhibitory activities at pH 7. The acetylated product (5) of compound 4 also inhibited COX-I and COX-II enzymes when tested at 250 microg ml(-1). Compounds 6 and 7 exhibited good antioxidant activity at concentrations of 125 and 250 microg ml(-1). Only compounds 1-3 exhibited topoisomerase-I and -II enzyme inhibitory activity at concentrations of 100, 200 and 200 microg ml(-1), respectively.


Asunto(s)
Antioxidantes/química , Apium , Inhibidores Enzimáticos/química , Fitoterapia , Extractos Vegetales/química , Antioxidantes/administración & dosificación , Ciclooxigenasa 1 , Ciclooxigenasa 2 , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/administración & dosificación , Humanos , Isoenzimas/antagonistas & inhibidores , Proteínas de la Membrana , Prostaglandina-Endoperóxido Sintasas , Semillas , Inhibidores de Topoisomerasa I , Inhibidores de Topoisomerasa II
7.
Phytomedicine ; 8(5): 362-9, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11695879

RESUMEN

Anthocyanins from tart cherries, Prunus cerasus L. (Rosaceae) cv. Balaton and Montmorency; sweet cherries, Prunus avium L. (Rosaceae); bilberries, Vaccinum myrtillus L. (Ericaceae); blackberries, Rubus sp. (Rosaceae); blueberries var. Jersey, Vaccinium corymbosum L. (Ericaceae); cranberries var. Early Black, Vaccinium macrocarpon Ait. (Ericaceae); elderberries, Sambucus canadensis (Caprifoliaceae); raspberries, Rubus idaeus (Rosaceae); and strawberries var. Honeoye, Fragaria x ananassa Duch. (Rosaceae), were investigated for cyclooxygenase inhibitory and antioxidant activities. The presence and levels of cyanidin-3-glucosylrutinoside 1 and cyanidin-3-rutinoside 2 were determined in the fruits using HPLC. The antioxidant activity of anthocyanins from cherries was comparable to the commercial antioxidants, tert-butylhydroquinone, butylated hydroxytoluene and butylated hydroxyanisole, and superior to vitamin E, at a test concentration of 125 microg/ml. Anthocyanins from raspberries and sweet cherries demonstrated 45% and 47% cyclooxygenase-I and cyclooxygenase-II inhibitory activities, respectively, when assayed at 125 microg/ml. The cyclooxygenase inhibitory activities of anthocyanins from these fruits were comparable to those of ibuprofen and naproxen at 10 microM concentrations. Anthocyanins 1 and 2 are present in both cherries and raspberry. The yields of pure anthocyanins 1 and 2 in 100 g Balaton and Montmorency tart cherries, sweet cherries and raspberries were 21, 16.5; 11, 5; 4.95, 21; and 4.65, 13.5 mg, respectively. Fresh blackberries and strawberries contained only anthocyanin 2 in yields of 24 and 22.5 mg/100 g, respectively. Anthocyanins 1 and 2 were not found in bilberries, blueberries, cranberries or elderberries.


Asunto(s)
Antocianinas/química , Antioxidantes/metabolismo , Inhibidores de la Ciclooxigenasa/metabolismo , Frutas/química , Antocianinas/aislamiento & purificación , Antocianinas/farmacología , Antioxidantes/farmacología , Bioensayo , Caprifoliaceae/química , Cromatografía Líquida de Alta Presión , Ciclooxigenasa 1 , Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa/farmacología , Ericaceae/química , Glucósidos/farmacología , Isoenzimas/antagonistas & inhibidores , Isoenzimas/metabolismo , Liposomas , Estructura Molecular , Oxidación-Reducción/efectos de los fármacos , Consumo de Oxígeno/efectos de los fármacos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Prostaglandina-Endoperóxido Sintasas/metabolismo , Rosaceae/química
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