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1.
Molecules ; 27(17)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36080241

RESUMO

The massive use of pesticides has brought great risks to food and environmental safety. It is necessary to develop reliable analytical methods and evaluate risks through monitoring studies. Here, a method was used for the simultaneous determination of flupyradifurone (FPF) and its two metabolites in fresh ginseng, dried ginseng, ginseng plants, and soil. The method exhibited good accuracy (recoveries of 72.8-97.5%) and precision (relative standard deviations of 1.1-8.5%). The field experiments demonstrated that FPF had half-lives of 4.5-7.9 d and 10.0-16.9 d in ginseng plants and soil, respectively. The concentrations of total terminal residues in soil, ginseng plants, dried ginseng, and ginseng were less than 0.516, 2.623, 2.363, and 0.641 mg/kg, respectively. Based on these results, the soil environmental risk assessment shows that the environmental risk of FPF to soil organisms is acceptable. The processing factors for FPF residues in ginseng were 3.82-4.59, indicating that the concentration of residues increased in ginseng after drying. A dietary risk assessment showed that the risk of FPF residues from long-term and short-term dietary exposures to global consumers were 0.1-0.4% and 12.07-13.16%, respectively, indicating that the application of FPF to ginseng at the recommended dose does not pose a significant risk to consumers.


Assuntos
Panax , Resíduos de Praguicidas , Poluentes do Solo , 4-Butirolactona/análogos & derivados , Monitoramento Ambiental/métodos , Panax/química , Resíduos de Praguicidas/análise , Piridinas , Medição de Risco , Solo/química , Poluentes do Solo/análise
2.
Biomed Chromatogr ; 36(4): e5312, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34981517

RESUMO

An effective method based on LC-MS/MS was established to determine the concentrations of flupyradifurone, difluoroacetic acid, and 6-chloronicotinic acid in pepper. On the basis of this method, the dissipation, processing factor, and dietary risk of flupyradifurone in pepper were investigated. The results show that the half-life of flupyradifurone in peppers was 2.6-3.8 days. The terminal residual concentration of flupyradifurone in the supervised trials was not higher than the maximum residue limit (MRL) for pepper in the Codex Alimentarius Commission (CAC) (0.9 mg kg-1 ) with the highest residual values of 0.53 mg kg-1 . The national estimated daily intake of flupyradifurone was 0.00094 mg kg-1 , based on the dietary structure of Chinese consumers and the terminal residues under field conditions. The risk quotient for flupyradifurone was 0.012, which was significantly < 1. The processing factor of flupyradifurone in dried pepper was 10.9-14.2, which indicated that drying increased the residual amounts of flupyradifurone in dried pepper, but the residual concentration was still lower than its MRL of 9 mg kg-1 established by CAC.


Assuntos
Resíduos de Praguicidas , Espectrometria de Massas em Tandem , 4-Butirolactona/análogos & derivados , Cromatografia Líquida/métodos , Resíduos de Praguicidas/análise , Piridinas , Medição de Risco , Espectrometria de Massas em Tandem/métodos
3.
Environ Sci Pollut Res Int ; 28(40): 57372-57385, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34091852

RESUMO

In this study, toxic effects of spirodiclofen and protective role of lycopene against toxic effects were investigated by using physiological, cytogenetic, anatomical, and biochemical parameters. Allium cepa L. bulbs were used as test material. The bulbs were divided into six groups as one control and five application groups. Bulb in the control group was germinated with tap water, and in treatment groups, 20-mg L-1 dose of spirodiclofen 215- and 430-mg L-1 doses of lycopene were applied. Spirodiclofen application caused a decrease in physiological parameters such as germination percentage, root length, and weight increase. Spirodiclofen administration caused a decrease in the percentage of mitotic index (MI) and an increase in DNA fragmentation, micronucleus (MN), and chromosomal aberration (CA) frequency. Spirodiclofen application caused an increase in the level of the oxidant compound malondialdehyde (MDA), changes in the level of antioxidant enzymes, and disruption of the oxidant/antioxidant balance in the cell. Molecular interactions between spirodiclofen and antioxidant enzymes were determined by molecular docking analysis. In addition to physiological, biochemical, and genetic abnormalities, spirodiclofen also caused deformations in the anatomy of the A. cepa root tip meristematic cells. Lycopene treatment showed a protective effect by suppressing the toxic effects of spirodiclofen, causing a significant improvement in the values of selected physiological, cytogenetic, anatomical, and biochemical parameters. As a result, spirodiclofen insecticide caused toxic effects on various parameters in A. cepa, which is a eukaryotic model organism. In order to elucidate the toxicity mechanism, each parameter is associated with each other. Molecular docking method has revealed the effects of spirodiclofen on antioxidant enzymes. Lycopene application together with spirodiclofen resulted in the regression of all toxic effects and improvement in the root tissue. This result shows that lycopene has a strong protective property against spirodiclofen toxicity.


Assuntos
Cebolas , Raízes de Plantas , 4-Butirolactona/análogos & derivados , Licopeno , Malondialdeído , Simulação de Acoplamento Molecular , Compostos de Espiro
4.
Chemosphere ; 261: 127760, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32731029

RESUMO

Predatory mites belonging to family Phytoseiidae (Acari: Mesostigmata) have long been considered as the most promising candidates for biological control of some economically important plant feeding mites and insects. Among them, Euseius scutalis (Athias-Henriot) is one of the most abundant predators and can be considered as an important component for integrated pest management (IPM) programs in Mediterranean citrus orchards. Evaluation of non-target and toxic effects of pesticides is crucial to measure their threats to E. scutalis. In this study, the effects of some selected acaricides (abamectin, etoxazole, spirodiclofen, spirotetramat and pyridaben), that were widely used in citrus orchards, on eggs, larvae, and adult females of E. scutalis were determined under laboratory conditions. In order to observe some possible results at "worst-case scenario", the test units were sprayed at maximum recommended doses. According to the results, abamectin and pyridaben respectively caused 18.00% and 33.50% mortality on eggs, 57.33% and 65.33% on larvae, 23.33% and 44.00% on adult females. While etoxazole was only toxic to the larvae with mortality rates reaching 55.33%, spirodiclofen and spirotetramat were harmless to all developmental stages of the predatory mite. In addition, abamectin, etoxazole and pyridaben caused a significant reduction in the egg production of E. scutalis when compared to the control. Accordingly, spirodiclofen and spirotetramat may be compatible with E. scutalis in IPM programs where it is implemented as a predator. However, further semi-field and/or field experiments are essential in order to draw a final conclusion on compatibility of the other three acaricides.


Assuntos
Acaricidas/toxicidade , Ácaros/efeitos dos fármacos , 4-Butirolactona/análogos & derivados , Animais , Compostos Aza , Citrus/efeitos dos fármacos , Feminino , Ivermectina/análogos & derivados , Larva/efeitos dos fármacos , Controle de Pragas , Praguicidas/farmacologia , Piridazinas , Compostos de Espiro
8.
BMC Vet Res ; 15(1): 309, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31464629

RESUMO

BACKGROUND: Non-steroidal anti-inflammatory drugs (NSAIDs) are an important tool in the management of canine osteoarthritis, with the most recent introduction into the category being grapiprant, a piprant that selectively targets the EP4 prostaglandin receptor. To date there have been no efficacy studies comparing grapiprant with other NSAIDs. A randomized, two-sequence, assessor-blinded study involving two separate experiments was undertaken to measure the potency and persistence of acute pain control over 24 h resulting from a single oral dose of either firocoxib (Previcox®) or grapiprant (Galliprant®) in an acute arthritis model. RESULTS: Force-plate derived lameness ratios (0, no force recorded on the plate; 1, normal force) for the untreated group remained at 0 for most post-arthritis induction (PAI) assessments in both experiments. Throughout Experiment 1, mean PAI lameness ratios of the firocoxib-treated group remained at or above 0.80. In the grapiprant-treated group, ratios were 0 at 5 and 7 h PAI (7 and 9 h post-treatment), and 0.16 at 10 h PAI (12 h post-treatment). For lameness ratios, relative to the firocoxib group, the control and grapiprant group ratios were significantly lower at each PAI assessment (p ≤ 0.026 and p < 0.001, respectively), except at 1.5 h PAI at which acute pain was still not installed in untreated control dogs. In Experiment 2 the mean lameness ratios for the control group were 0 at 3, 5 and 7 h PAI, and in the grapiprant group at 5, 7 and 10 h PAI (i.e., 19, 21, and 24 h post-treatment). In the firocoxib group the lowest mean lameness ratio of 0.36 occurred at 3 h PAI (i.e. 17 h post-treatment). Except at 1.5 and 3 h PAI (i.e. 15.5 and 17 h post-treatment), due to the needed time for pain to install in the untreated control dogs, the lameness ratio differences between the firocoxib and both the control and grapiprant groups were significant at all assessments (p ≤ 0.033 for both groups). No significant differences were detected between the grapiprant and control groups in either experiment. CONCLUSIONS: Firocoxib treatment prior to induction of arthritis in dogs resulted in a high level of analgesia from the first post-treatment assessment at 1.5 h through 24 h post-treatment. The reduction in lameness provided by firocoxib was consistently superior to that provided by grapiprant, which was not significantly different from untreated controls.


Assuntos
4-Butirolactona/análogos & derivados , Artrite Experimental/veterinária , Doenças do Cão/tratamento farmacológico , Sulfonas/uso terapêutico , Compostos de Sulfonilureia/uso terapêutico , 4-Butirolactona/uso terapêutico , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Experimental/induzido quimicamente , Artrite Experimental/tratamento farmacológico , Cães , Coxeadura Animal , Distribuição Aleatória , Ácido Úrico/toxicidade
9.
Int J Cancer ; 143(11): 2698-2708, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29974464

RESUMO

Higher lignan exposure has been associated with lower all-cause mortality (ACM) and breast cancer-specific mortality (BCSM) for postmenopausal breast cancer patients. However, the biological mechanisms underpinning these associations are still unclear. We investigated for the first time whether and to what extent the association between enterolactone (ENL), the major lignan metabolite, and postmenopausal breast cancer prognosis is mediated by inflammatory biomarkers. Circulating concentrations of ENL and inflammatory markers were measured in a population-based prospective cohort of 1,743 breast cancer patients recruited between 2002 and 2005 and followed-up until 2009. Hazard ratios (HR) and 95% CIs were estimated using multivariable Cox regression. Mediation analysis was performed to estimate the percentage association between ENL (log2) and ACM, BCSM and distant disease-free survival (DDFS), which is mediated by C-reactive protein (CRP) (log2), as the strongest potential mediator, and also interleukin (IL)-10. Median serum/plasma ENL and CRP concentrations for all patients, including 180 deceased patients, were 23.2 and 17.5 nmol/L, and 3.2 and 6.5 mg/l, respectively. ENL concentrations were significantly inversely associated with ACM, BCSM and DDFS (per doubling of ENL concentrations: HRs 0.93 [0.87, 0.99], 0.91 [0.84, 0.99] and 0.92 [0.87, 0.99]), after adjusting for prognostic factors and BMI. Estimated 18, 14 and 12% of the effects of ENL on ACM, BCSM and DDFS, respectively, were mediated through CRP. No mediational effect of IL-10 was found. We provide first evidence that the proinflammatory marker CRP may partially mediate the association of ENL with postmenopausal breast cancer survival, which supports hormone-independent mechanisms.


Assuntos
4-Butirolactona/análogos & derivados , Biomarcadores/sangue , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Inflamação/sangue , Lignanas/sangue , Pós-Menopausa/sangue , 4-Butirolactona/sangue , Idoso , Estudos de Casos e Controles , Intervalo Livre de Doença , Feminino , Humanos , Inflamação/patologia , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos
10.
J Econ Entomol ; 111(5): 2201-2207, 2018 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-29955822

RESUMO

In the High Plains, sugarcane aphid, Melanaphis sacchari Zehntner (Hemiptera: Aphididae), colonize grain sorghum, Sorghum bicolor (L) Moench (Cyperales: Poaceae), when it is in reproductive stages and aphid populations increase rapidly. Sugarcane aphid management recommendations based on aphid densities have been implemented in southern United States, but have not been assessed in the High Plains. Therefore, the goal of this work was to validate whether these guidelines can provide effective suppression of the aphids and improve yield. In a 2-y field experiment, sorghum susceptible (DKS44-20) and resistant (DKS37-07) to sugarcane aphids, with and without insecticide (clothianidin) seed treatments, was exposed to natural aphid infestations and treated with a foliar insecticide (flupyradifurone) once sugarcane aphid densities exceeded 50 per leaf. Further, to assess the effects of these tactics on sorghum yield, data were collected from plots that were not treated at the threshold. In both years, foliar insecticide applied at the density-based threshold decreased aphid numbers across sorghum hybrids with and without seed treatments and aphid densities remained below threshold for the remainder of the season. Yield of sorghum depended on sugarcane aphid pressure-when their densities were high (2016), the resistant hybrid with and without the foliar spray outperformed the unsprayed susceptible hybrid, while the susceptible hybrid had higher yields than resistant hybrid when sugarcane aphid pressure was low (2017). Outcomes of this work support the notion that a well-timed foliar application can alleviated losses in yield in sorghum in the Texas Panhandle and potentially other regions of the High Plains.


Assuntos
4-Butirolactona/análogos & derivados , Afídeos , Guanidinas/administração & dosagem , Controle de Insetos/métodos , Inseticidas/administração & dosagem , Neonicotinoides/administração & dosagem , Piridinas/administração & dosagem , Tiazóis/administração & dosagem , 4-Butirolactona/administração & dosagem , Animais , Densidade Demográfica , Sorghum
11.
Lett Appl Microbiol ; 65(5): 388-394, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28833381

RESUMO

Shewanella spp. are the common spoilage organisms found in aquatic food products stored at low temperature and their spoilage mechanism has been reported to be mediated by quorum sensing (QS). However, the specifically expressed proteins responding to N-acyl homoserine-lactone (AHLs) were seldom reported. This study aims to evaluate the effects of different AHL signal molecules on Shewanella putrefaciens Z4 isolated from refrigerated turbot (Scophthalmus maximus) at the proteome level. The results revealed that exogenous AHLs were utilized as QS signal molecules by S. putrefaciens Z4, and AHLs were not degraded by intracellular or extracellular enzymes secreted by S. putrefaciens Z4. Twenty-three differently expressed spots upon the addition of AHLs were selected and identified by liquid chromatography-mass spectrometry (LC-MS). The results indicated that proteins involving in growth and metabolism (i.e. citrate synthase, succinate semialdehyde dehydrogenase), environment adaptation and regulators (i.e. polysaccharide deacetylases, transaldolase) were down-regulated upon three kinds of AHLs (C4-HSL, C6-HSL and O-C6-HSL), whereas the abundance of stress response protein and DNA ligase were elevated by the addition of exogenous AHLs. Moreover, the effects of exogenous C6-HSL and O-C6-HSLwere prominent. These results provide evidence that AHL-based QS signal molecules affected some important metabolic properties of S. putrefaciens. SIGNIFICANCE AND IMPACT OF THE STUDY: N-acyl homoserine lactone (AHLs)-based quorum sensing signal molecules involving in the behavior regulation in most of the Gram-negative bacteria have widely been reported. This study aims to evaluate the effect of AHLs on Shewanella putrefaciens Z4 at the proteome level. It provides the theoretic basis for elucidating the spoilage mechanism of Shewanella spp., the common spoilage micro-organism in refrigerated marine aquatic food products.


Assuntos
4-Butirolactona/análogos & derivados , Proteínas de Bactérias/química , Contaminação de Alimentos/análise , Shewanella putrefaciens/química , 4-Butirolactona/metabolismo , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cromatografia Líquida , Espectrometria de Massas , Perciformes/microbiologia , Proteômica , Percepção de Quorum , Alimentos Marinhos/microbiologia , Shewanella putrefaciens/genética , Shewanella putrefaciens/isolamento & purificação , Shewanella putrefaciens/fisiologia
12.
Mar Drugs ; 15(6)2017 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-28635645

RESUMO

Three new cembrene diterpenoids, sarcoehrenbergilid A-C (1-3), along with four known diterpenoids, sarcophine (4), (+)-7α,8ß-dihydroxydeepoxysarcophine (5), sinulolide A (6), and sinulolide B (7), and one steroid, sardisterol (8), were isolated and characterized from a solvent extract of the Red Sea soft coral Sarcophyton ehrenbergi. Chemical structures were elucidated by NMR and MS analyses with absolute stereochemistry determined by X-ray analysis. Since these isolated cembrene diterpenes contained 10 or more carbons in a large flexible ring, conformer stabilities were examined based on density functional theory calculations. Anti-proliferative activities for 1-8 were evaluated against three human tumor cell lines of different origins including the: lung (A549), colon (Caco-2), and liver (HepG2). Sardisterol (8) was the most potent of the metabolites isolated with an IC50 of 27.3 µM against the A549 cell line. Since an elevated human-cancer occurrence is associated with an aberrant receptor function for the epidermal growth factor receptor (EGFR), molecular docking studies were used to examine preferential metabolite interactions/binding and probe the mode-of-action for metabolite-anti tumor activity.


Assuntos
Antozoários/química , Proliferação de Células/efeitos dos fármacos , Diterpenos/química , Diterpenos/farmacologia , Éter/química , 4-Butirolactona/análogos & derivados , 4-Butirolactona/farmacologia , Células A549 , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Células CACO-2 , Linhagem Celular Tumoral , Células Hep G2 , Humanos , Oceano Índico , Espectroscopia de Ressonância Magnética/métodos , Simulação de Acoplamento Molecular
13.
PLoS One ; 12(2): e0170281, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28151972

RESUMO

Pilocarpus microphyllus Stapf ex Wardleworth (jaborandi, Rutaceae) is one of the most important Brazilian medicinal species owing to its content of pilocarpine (PIL), an alkaloid used for treating glaucoma and xerostomia. This species contains another alkaloid, epiisopiloturine (EPI), which has demonstrated effectiveness against schistosomiasis. The aim of this work was to assess seasonal changes of PIL and EPI in three populations of cultivated P. microphyllus from northeastern Brazil over one year, including the dry and rainy seasons. Alkaloid profiles were correlated to phenotypic and genetic patterns in the morphological and molecular characterizations. PIL was the primary alkaloid and its levels differed among populations in all months except September. The S01 population (green line) showed an especially high PIL content compared to populations S02 and S03 (traditional line), which had similar alkaloid contents. PIL content gradually decreased in the three populations in the rainy season.EPI content was significantly different between the green line (S01) and the traditional line (S02 and S03).S01 had a significantly lower EPI content in all months, demonstrating that it was not the best source for EPI extraction. Inter simple sequence repeat (ISSR) markers and morphological analyses clearly separated S01 from S02 and S03, in agreement with the alkaloid results. This study shows the first correlation between the chemical, morphological, and molecular markers of P. microphyllus and highlights the potential benefits of a multidisciplinary research approach aimed at supporting both industry and conservation of natural resources.


Assuntos
Alcaloides/análise , Pilocarpus/química , Plantas Medicinais/química , 4-Butirolactona/análogos & derivados , 4-Butirolactona/análise , Brasil , DNA de Plantas/genética , Genética Populacional , Imidazóis/análise , Repetições de Microssatélites , Pilocarpina/análise , Pilocarpus/anatomia & histologia , Pilocarpus/genética , Folhas de Planta/anatomia & histologia , Folhas de Planta/química , Folhas de Planta/genética , Plantas Medicinais/anatomia & histologia , Plantas Medicinais/genética , Estações do Ano
14.
Molecules ; 21(6)2016 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-27322236

RESUMO

Kinsenoside, the herb-derived medicine isolated from the plant Anoect chilus, has diverse pharmacological actions, and it is considered to be a promising antihyperlipidemic drug candidate. This study evaluates the effects of kinsenoside on CYP enzyme-mediated drug metabolism in order to predict the potential for kinsenoside-drug interactions. Kinsenoside was tested at different concentrations of 0.1, 0.3, 1, 3, 10, 30, and 100 µM in human liver microsomes. The c Cktail probe assay based on liquid chromatography-tandem mass spectrometry was conducted to measure the CYP inhibitory effect of kinsenoside. Subsequently, the metabolism profiles of amlodipine and lovastatin in human liver microsomes were analyzed following co-incubation with kinsenoside. The concentration levels of the parent drug and the major metabolites were compared with the kinsenoside-cotreated samples. The effect of kinsenoside was negligible on the enzyme activity of all the CYP isozymes tested even though CYP2A6 was slightly inhibited at higher concentrations. The drug-drug interaction assay also showed that the concomitant use of kinsenoside has a non-significant effect on the concentration of lovastatin or amlodipine, and their major metabolites. So, it was concluded that there is almost no risk of drug interaction between kinsenoside and CYP drug substrates via CYP inhibition.


Assuntos
4-Butirolactona/análogos & derivados , Citocromo P-450 CYP2A6/metabolismo , Hipolipemiantes/farmacologia , Inativação Metabólica/genética , Monossacarídeos/farmacologia , 4-Butirolactona/química , 4-Butirolactona/farmacologia , Anlodipino/metabolismo , Anlodipino/farmacologia , Cromatografia Líquida , Inibidores das Enzimas do Citocromo P-450/química , Inibidores das Enzimas do Citocromo P-450/farmacologia , Sistema Enzimático do Citocromo P-450/efeitos dos fármacos , Interações Medicamentosas , Humanos , Hipolipemiantes/química , Inativação Metabólica/efeitos dos fármacos , Lovastatina/metabolismo , Lovastatina/farmacologia , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Monossacarídeos/química , Especificidade por Substrato , Espectrometria de Massas em Tandem
15.
J Org Chem ; 80(1): 681-4, 2015 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-25423410

RESUMO

A concise, modular and efficient synthesis of the title natural products is reported. Prominent steps include (i) one-pot assembly of a key ß-aryl-α-benzoylbutenolide building block by regiocontrolled "click-unclick" oxazole-ynone Diels-Alder cycloaddition/cycloreversion and ensuing 2-alkoxyfuran hydrolysis and (ii) a protecting group-free vinylogous Knoevenagel condensation enabling rapid access to cadiolides A, B, and D from a common precursor.


Assuntos
4-Butirolactona/análogos & derivados , Antibacterianos/síntese química , Urocordados/química , 4-Butirolactona/síntese química , 4-Butirolactona/química , Animais , Antibacterianos/química , Organismos Aquáticos/química , Ciclização , Estrutura Molecular
16.
J Nutr ; 144(3): 352-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24401816

RESUMO

Phytoestrogens have been associated with subtle hormonal changes, although effects on fecundity are unknown. Our objective was to evaluate the association between male and female urinary phytoestrogen (isoflavone and lignan) concentrations and time to pregnancy (TTP) in a population-based cohort of 501 couples desiring pregnancy and discontinuing contraception. Couples were followed for 12 mo or until pregnancy. Fecundability ORs (FORs) and 95% CIs were estimated after adjusting for age, body mass index, race, site, creatinine, supplement use, and physical activity in relation to female, male, and joint couple concentrations. Models included the phytoestrogen of interest and the sum of the remaining individual phytoestrogens. FORs <1 denote a longer TTP and FORs >1 a shorter TTP. Urinary lignan concentrations were higher, on average, among female partners of couples who became pregnant during the study compared with women who did not become pregnant (median enterodiol: 118 vs. 80 nmol/L; P < 0.10; median enterolactone: 990 vs. 412 nmol/L; P < 0.05) and were associated with significantly shorter TTP in models based on both individual and couples' concentrations (couples' models: enterodiol FOR, 1.13; 95% CI: 1.02, 1.26; enterolactone FOR, 1.11; 95% CI: 1.01, 1.21). Male lignan concentrations were not associated with TTP, nor were isoflavone concentrations. Sensitivity analyses showed that associations observed are unlikely to be explained by potential unmeasured confounding by lifestyle or other nutrients. Our results suggest that female urinary lignan concentrations at levels characteristic of the U.S. population are associated with a shorter TTP among couples who are attempting to conceive, highlighting the importance of dietary influences on fecundity.


Assuntos
Lignanas/urina , Fitoestrógenos/administração & dosagem , Tempo para Engravidar/efeitos dos fármacos , 4-Butirolactona/análogos & derivados , 4-Butirolactona/urina , Adolescente , Adulto , Índice de Massa Corporal , Dieta , Feminino , Humanos , Isoflavonas/administração & dosagem , Isoflavonas/urina , Lignanas/administração & dosagem , Masculino , Gravidez , Estudos Prospectivos , Fatores Socioeconômicos , Tempo para Engravidar/fisiologia , Adulto Jovem
17.
Int J Cancer ; 135(4): 923-33, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24436155

RESUMO

We previously reported that high concentrations of enterolactone, a lignan metabolite, are associated with lower mortality in 1,140 breast cancer patients from Germany. Using an extended set of 2,182 patients aged 50-74 years at diagnosis (2001-2005) and prospectively followed up until 2009, we investigated whether the association with mortality differs by lifestyle factors and tumor characteristics. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated using multivariable Cox regression. Potential differential effects by tumor characteristics and lifestyle factors were assessed and a meta-analysis of five studies addressing lignan exposure and breast cancer prognosis was performed to summarize evidence. Median enterolactone concentrations were 17.4 (± 30.5 standard deviation) and 22.9 nmol L(-1) (± 44.8), respectively, for 269 deceased and 1,913 patients still alive. High enterolactone concentrations were significantly associated with lower all-cause mortality (per 10 nmol L(-1) : HR 0.94, 95% CI 0.90-0.98), breast cancer-specific mortality (HR 0.94, 0.89-0.99), and distant disease-free survival (HR 0.94, 0.90-0.98). Associations were found for stage 0-IIIA but not for stage IIIB-IV disease (p(het) = 0.01) and were stronger in patients with BMI <25 kg m(-2) than those with BMI ≥ 25 (p(het) = 0.04). In patients with healthy lifestyle (BMI <25, nonsmoker, physically active), the inverse association with all-cause mortality was still apparent (HR 0.92, 0.85-0.99). The meta-analysis yielded significant associations both for all-cause (HR 0.57, 0.42-0.78) and breast cancer-specific mortality (HR 0.54, 0.39-0.75). Our findings show that high lignan exposure is associated with reduced mortality in breast cancer patients. The inverse association observed in this study cannot be entirely explained by a healthy lifestyle.


Assuntos
4-Butirolactona/análogos & derivados , Neoplasias da Mama/sangue , Dieta , Lignanas/sangue , 4-Butirolactona/sangue , Idoso , Biomarcadores Tumorais/sangue , Índice de Massa Corporal , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/mortalidade , Progressão da Doença , Intervalo Livre de Doença , Feminino , Alemanha , Humanos , Estilo de Vida , Pessoa de Meia-Idade , Pós-Menopausa , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco
18.
Environ Monit Assess ; 185(12): 10473-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23880916

RESUMO

The dissipation, residues, and distribution of spirodiclofen, a new type of insecticide and acaricide that belongs to the class of ketoenols or tetronic acids, in citrus were investigated in this study. Risk assessment of sprodiclofen was also conducted based on those data. The open-field experiments were conducted in Guangdong, Fujian, and Guangxi of China. Results showed that the half-lives in citrus ranged from 6.5 to 13.6 days at three sites. The terminal residues of spirodiclofen were all below the FAO/WHO maximum residue limit of 0.5 mg/kg in citrus, when they were determined 14 days after final application. Distribution of spirodiclofen in peel and flesh was analyzed, and residues were found to be concentrated on peel. Risk assessment was performed by calculation of risk quotient, which showed that the use of spirodiclofen is comparably safe for humans.


Assuntos
4-Butirolactona/análogos & derivados , Citrus/química , Inseticidas/análise , Resíduos de Praguicidas/análise , Compostos de Espiro/análise , 4-Butirolactona/análise , China , Monitoramento Ambiental , Contaminação de Alimentos/análise , Contaminação de Alimentos/estatística & dados numéricos , Meia-Vida , Medição de Risco
19.
Phys Chem Chem Phys ; 15(18): 6935-44, 2013 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-23549300

RESUMO

Dimers and higher order oligomers, whether in the gas or particle phase, can affect important atmospheric processes such as new particle formation, and gas-particle partitioning. In this study, the thermodynamics of dimer formation from various oxidation products of α-pinene ozonolysis are investigated using a combination of Monte Carlo configuration sampling, semi-empirical and density functional theory (DFT) quantum mechanics, and continuum solvent modeling. Favorable dimer formation pathways are found to exist in both gas and condensed phases. The free energies of dimer formation are used to calculate equilibrium constants and expected dimer concentrations under a variety of conditions. In the gas phase, favorable pathways studied include formation of non-covalent dimers of terpenylic acid and/or cis-pinic acid and a covalently-bound peroxyhemiacetal. Under atmospherically relevant conditions, only terpenylic acid forms a dimer in sufficient quantities to contribute to new particle formation. Under conditions typically used in laboratory experiments, several dimer formation pathways may contribute to particle formation. In the condensed phase, non-covalent dimers of terpenylic acid and/or cis-pinic acid and covalently-bound dimers representing a peroxyhemiacetal and a hydrated aldol are favorably formed. Dimer formation is both solution and temperature dependent. A water-like solution appears to promote dimer formation over methanol- or acetonitrile-like solutions. Heating from 298 K to 373 K causes extensive decomposition back to monomers. Dimers that are not favorably formed in either the gas or condensed phase include hemi-acetal, ester, anhydride, and the di(α-hydroxy) ether.


Assuntos
Aerossóis/química , 4-Butirolactona/análogos & derivados , 4-Butirolactona/química , Acetatos/química , Dimerização , Gases/química , Isomerismo , Método de Monte Carlo , Termodinâmica
20.
J Nutr ; 143(6): 986S-94S, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23596167

RESUMO

Isoflavones and lignans are plant-derived dietary compounds generally believed to be beneficial to human health. We investigated the extent to which sociodemographic (age, sex, race-ethnicity, education, and income) and lifestyle variables (smoking, alcohol consumption, BMI, physical activity, and dietary supplement use) were correlates of spot urine concentration for daidzein, genistein, O-desmethylangolensin (DMA), equol, enterodiol, and enterolactone in the U.S. population aged ≥ 20 y (NHANES 2003-2006). We performed correlation analyses with continuous variables and calculated stratified unadjusted geometric means for each sociodemographic and lifestyle variable. We used bivariate significance testing and covariate adjustment by use of multiple regression models to identify influential variables and used ß coefficients to estimate relative effects. Urine creatinine was also included in our analyses because of its use in correcting for variable dilution in spot urine samples. We observed many significant (P < 0.05) associations with the sociodemographic and lifestyle variables that withstood covariate adjustment. Smoking was a significant correlate of urine DMA and enterolactone, with concentrations at least 25% lower in smokers vs. nonsmokers. Consumers of 1 daily alcoholic drink vs. none were estimated to have 18-21% lower urine equol and DMA concentrations. A 25% increase in BMI was associated with a 21% lower urine enterolactone concentration, and increasing physical activity was associated with a >6% higher urine enterolactone concentration. Dietary supplement use was not significantly associated with any of the urine phytoestrogens. Overall, we found that relationships between sociodemographic and lifestyle variables and urine phytoestrogen concentration were highly compound and class specific.


Assuntos
Estilo de Vida , Inquéritos Nutricionais , Fitoestrógenos/urina , Fatores Socioeconômicos , 4-Butirolactona/análogos & derivados , 4-Butirolactona/urina , Adulto , Fatores Etários , Consumo de Bebidas Alcoólicas/urina , Índice de Massa Corporal , Equol/urina , Exercício Físico/fisiologia , Feminino , Humanos , Isoflavonas/urina , Lignanas/urina , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Fumar/urina , Estados Unidos
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