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1.
Sci Total Environ ; 874: 162498, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-36863589

RESUMO

This study quantifies golf course pesticide risk in five regions across the US (Florida, East Texas, Northwest, Midwest, and Northeast) and three countries in Europe (UK, Denmark, and Norway) with the objective of determining how pesticide risk on golf courses varied as a function of climate, regulatory environment, and facility-level economic factors. The hazard quotient model was used to estimate acute pesticide risk to mammals specifically. Data from 68 golf courses are included in the study, with a minimum of at least five golf courses in each region. Though the dataset is small, it is representative of the population at confidence level of 75 % with a 15 % margin of error. Pesticide risk appeared to be similar across US regions with varied climates, and significantly lower in the UK, and lowest in Norway and Denmark. In the Southern US (East Texas and Florida), greens contribute most to total pesticide risk while in nearly all other regions fairways make the greatest contribution to overall pesticide risk. The relationship between facility-level economic factors such as maintenance budget was limited in most regions of the study, except in the Northern US (Midwest, Northwest, and Northeast) where maintenance and pesticide budget correlated to pesticide risk and use intensity. However, there was a strong relationship between regulatory environment and pesticide risk across all regions. Pesticide risk was significantly lower in Norway, Denmark, and the UK, where twenty or fewer active ingredients were available to golf course superintendents, than it was in US where depending on the state between 200 and 250 pesticide active ingredients were registered for use on golf courses.


Assuntos
Golfe , Praguicidas , Animais , Praguicidas/análise , Europa (Continente) , Noruega , Clima , Mamíferos
2.
Sci Total Environ ; 783: 146840, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-33866184

RESUMO

This study develops a framework that quantifies golf course pesticide risk, explores environmental and economic factors that may be responsible for the observed risk, develops a method to compare golf course pesticide risk to other agricultural crops and investigates how pesticide risk on golf courses can be most effectively reduced. To quantify pesticide risk, we adapt the Environmental Impact Quotient (EIQ) and hazard quotient models for use on golf courses. The EIQ model provides an estimate of overall environmental risk, while the hazard quotient model, as applied here, provides an estimate of pesticide risk to mammals. This novel framework was applied to twenty-two courses in Wisconsin and New York, USA. Using both pesticide risk models, all twenty-two golf courses showed a high coefficient of variation of pesticide risk (<0.76). Within a golf course, mean absolute pesticide risk was at least two times higher on fairways than on greens, tees, or roughs. Mean area normalized risk was at least three times higher on greens than the other three golf course components. Pesticide risk of a component-weighted average of greens, tees, fairways and roughs on each course were within the range of pesticide risk calculated for five other agricultural crops. Our data suggest that variation in pesticide risk on golf courses is related to economic factors, such as maintenance budget, and can be effectively lowered by reducing pesticide use on fairways and selecting products of lower risk. To assist golf course superintendents in developing programs that lower pesticide risk, a new metric was developed: the Risk to Intensity Quotient (RIQ). The RIQ is the ratio of pesticide risk to use intensity and quantifies the average risk of product selection by a golf course superintendent.


Assuntos
Golfe , Praguicidas , Animais , Meio Ambiente , New York , Praguicidas/análise , Wisconsin
3.
J Food Prot ; 80(9): 1478-1488, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28786718

RESUMO

The 1986 Food Research Institute-Tanaka et al. model predicts the safety of shelf-stable process cheese spread formulations using the parameters of moisture, pH, NaCl, and disodium phosphate (DSP) to inhibit toxin production by Clostridium botulinum. Although this model is very reliable for predicting safety for standard-of-identity spreads, the effects of additional factors have not been considered. The objective of this study was to create a predictive model to include the interactive effect of moisture, pH, fat, sorbic acid, and potassium-based replacements for NaCl and DSP to reflect modern reduced-sodium recipes. Eighty formulations were identified using a central composite design targeting seven factors: 50 to 60% moisture, pH 5.4 to 6.2, 0 to 0.2% sorbic acid, 10 to 30% fat, 1.7 to 2.4% NaCl, 0.8 to 1.6% DSP, and 0 to 50% potassium replacement for sodium salts. Samples were inoculated with proteolytic C. botulinum spores at 3 log spores per g, hot filled into sterile vials, and stored anaerobically at 27°C. Samples were assayed at 0, 1, 2, 3, 4, 8.5, 17.5, 26, and 40 weeks for the presence of botulinum toxin using the mouse bioassay. A parametric survival model was fit to the censored time-to-toxin data. All linear, quadratic, and pairwise effects were considered for model fit. As hypothesized, the effects of pH, sorbate, moisture, DSP, and NaCl were highly significant (P < 0.001). Fat concentration and potassium replacement effects were significant at P < 0.021 and P < 0.057, respectively. The model consistently predicted the safety failure of the toxic samples, but it also predicted failure for some samples that were not toxic. This model is an adjunct to existing models by adding the factors of potassium salts, fat, and sorbic acid to predict the botulinal safety of prepared process cheese products but is not intended to be a substitute for formulation evaluation by a competent process authority.


Assuntos
Toxinas Botulínicas/biossíntese , Queijo/microbiologia , Clostridium botulinum/crescimento & desenvolvimento , Microbiologia de Alimentos , Conservação de Alimentos/métodos , Animais , Clostridium botulinum/efeitos dos fármacos , Clostridium botulinum/metabolismo , Qualidade de Produtos para o Consumidor , Humanos , Concentração de Íons de Hidrogênio , Sódio , Temperatura
4.
J Chem Ecol ; 41(4): 409-17, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25845354

RESUMO

Caterpillars of Cactoblastis cactorum secrete onto the surface of host cactuses droplets of an oily fluid that issues from the orifices of their paired mandibular glands. The fluid contains a series of 2-acyl-1,3-cyclohexanediones that, collectively, have been shown to elicit trail-following behavior from the caterpillars. This study reports the results of bioassays to determine the ability of two specific compounds, previously shown to be prominent components of the mandibular glands of pyralid caterpillars, 4-hydroxy-2-oleoyl-1,3-cyclohexanedione and 2-oleoyl-1,3-cyclohexanedione, to elicit trail-following behavior from the larvae of C. cactorum. Additionally bioassayed were structural fragments of these molecules. The relative effectiveness of the chemicals in eliciting trail following, the effect of varying concentration on the trail-following response, the importance of specific functional groups to the trail-following response, and the threshold sensitivity of the caterpillar to the pheromone were determined. The study showed that while all the tested compounds elicited some degree of trail following, they differed significantly in their effectiveness. The most effective of the compounds was 4-hydroxy-2-oleoyl-1,3-cyclohexanedione, which, on a per unit volume basis, was as effective as whole gland extract. Caterpillars secreted large quantities of fluid from the glands, and the threshold response to 4-hydroxy-2-oleoyl-1,3-cyclohexanedione occurred at a relative high application rate compared to trail pheromones of other social caterpillars and eusocial insects. This and the observation that the trail marker is secreted from the mandibular glands suggests that the use of 2-acyl-1,3-cyclohexanediones as trail markers is secondary, and that these compounds function primarily in some other, as yet undetermined, context.


Assuntos
Comunicação Animal , Cicloexanonas/metabolismo , Mariposas/fisiologia , Feromônios/metabolismo , Animais , Larva/crescimento & desenvolvimento , Larva/fisiologia , Mariposas/crescimento & desenvolvimento , Atividade Motora
5.
J Insect Sci ; 14: 64, 2014 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-25373211

RESUMO

The cactus moth, Cactoblastis cactorum (Berg) (Lepidoptera: Pyralidae), spends most of its larval life feeding within the cladodes of Opuntia cactuses, but the gregarious caterpillars begin their life outside the plant, and in the later instars make intermittent excursions over plant surfaces to access new cladodes and to thermoregulate. The study reported here showed that when the caterpillars move en masse, they mark and follow trails that serve to keep the cohort together. Artificial trails prepared from hexane extracts of the caterpillar's paired mandibular glands were readily followed by the caterpillars. The glands are remarkably large, and their fluid contents, which constitute approximately 1% of the total wet mass of a caterpillar, are secreted onto the substrate as they move. Although the caterpillars also lay down copious quantities of silk, the material in itself neither elicits trail following nor is it a requisite component of pathways that elicit trail following. Previous analyses of the mandibular glands of other species of pyralid caterpillars showed that they contain a series of structurally distinct 2-acyl-1,3 cyclohexane diones. Chemical analysis indicates that the glands of C. cactorum contain structurally similar compounds, and bio- assays indicate that trail following occurs in response to these chemicals. While the mandibular glands' fluids have been shown to act as semiochemicals, effecting both interspecific and intra- specific behavior in other species of pyralids, the present study is the first to report their use as a trail pheromone.


Assuntos
Mariposas/fisiologia , Atividade Motora/fisiologia , Comunicação Animal , Animais , Larva/fisiologia , Odorantes
6.
Biochem Biophys Res Commun ; 351(3): 708-12, 2006 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-17084817

RESUMO

Phosphorylation and O-GlcNAcylation of keratin 18 (K18) are highly dynamic and involve primarily independent K18 populations. We used in vitro phosphorylation and O-GlcNAcylation of wild-type, phospho-Ser52, glyco-Ser48, and Ser-to-Ala mutant 17mer peptides (K18 amino acids 40-56), which include the major K18 glycosylation (Ser48) and phosphorylation (Ser52) sites, to address whether each modification blocks the other. The glyco-K18 peptide blocks Ser52 phosphorylation by protein kinase C, an in vivo K18 kinase, while the phospho-K18 peptide blocks its O-GlcNAcylation. Our findings support the reciprocity of these two post-translational modifications. Therefore, regulation of protein Ser/Thr phosphorylation and glycosylation at proximal sites can be interdependent and provides a potential mechanism of counter regulation.


Assuntos
Glicina/química , Queratina-18/química , Serina/química , Acilação , Substituição de Aminoácidos , Peptídeos/química , Fosforilação , Relação Estrutura-Atividade
7.
Biochemistry ; 43(26): 8528-40, 2004 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-15222764

RESUMO

The conjugation of peptides derived from the HIV TAT protein to membrane-impermeant molecules has gained wide acceptance as a means for intracellular delivery. Numerous studies have addressed the mechanism of uptake and kinetics of TAT translocation, but the cytosolic concentrations and bioavailability of the transported cargo have not been well-characterized. The current paper utilizes a microanalytical assay to perform quantitative single-cell measurements of the concentration and accessibility of peptide-based substrates for protein kinase B (PKB) and Ca(2+)/calmodulin-activated kinase II. The substrate peptide and TAT were conjugated through a releasable linker, either a disulfide or photolabile bond. Free substrate peptide concentrations of approximately 10(-20)-10(-18) moles were attainable in a cell when substrates were delivered utilizing these conjugates. The substrate peptides delivered as a disulfide conjugate were often present in the cytosol as several oxidized forms. Brief exposure of cells loaded with the photolabile conjugates to UVA light released free substrate peptide into the cytosol. Substrate peptide delivered by either conjugate was accessible to cytosolic kinase as demonstrated by the efficient phosphorylation of the peptide when the appropriate kinase was active. After incubation of the conjugated substrate with cells, free, kinase-accessible substrate was detectable in less than 30 min. Release of the majority of loaded substrate peptide from sequestered organelles occurred within 1 h. The utility of the photocleavable conjugates was demonstrated by measuring the activation of PKB in 3T3 cells after addition of varying concentrations of platelet-derived growth factor.


Assuntos
Produtos do Gene tat/química , Fosfotransferases/química , Animais , Transporte Biológico , Western Blotting , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Citosol/metabolismo , Relação Dose-Resposta a Droga , Eletroforese Capilar , Ativação Enzimática , Fluoresceína/farmacologia , Humanos , Cinética , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Células NIH 3T3 , Peptídeos/química , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Ratos , Temperatura , Fatores de Tempo , Raios Ultravioleta , Proteínas Quinases p38 Ativadas por Mitógeno
8.
J Agric Food Chem ; 52(4): 916-26, 2004 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-14969551

RESUMO

The importance of dietary sulforaphane in helping maintain good health continues to gain support within the health-care community and awareness among U.S. consumers. In addition to the traditional avenue for obtaining sulforaphane, namely, the consumption of appropriate cruciferous vegetables, other consumer products containing added glucoraphanin, the natural precursor to sulforaphane, are now appearing in the United States. Crucifer seeds are a likely source for obtaining glucoraphanin, owing to a higher concentration of glucoraphanin and the relative ease of processing seeds as compared to vegetative parts. Seeds of several commonly consumed crucifers were analyzed not only for glucoraphanin but also for components that might have negative health implications, such as certain indole-containing glucosinolates and erucic acid-containing lipids. Glucoraphanin, 4-hydroxyglucobrassicin, other glucosinolates, and lipid erucic acid were quantified in seeds of 33 commercially available cultivars of broccoli, 4 cultivars each of kohlrabi, radish, cauliflower, Brussels sprouts, kale, and cabbage, and 2 cultivars of raab.


Assuntos
Brassicaceae/química , Glucose/análogos & derivados , Glucose/análise , Glucosinolatos , Imidoésteres/análise , Indóis/análise , Monossacarídeos/análise , Sementes/química , Brassica/química , Cromatografia Líquida de Alta Pressão , Oximas , Raphanus/química , Sulfóxidos
9.
J Environ Qual ; 32(2): 447-55, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12708667

RESUMO

The TurfPQ model was used to simulate the runoff of 15 pesticides commonly applied to creeping bentgrass (Agrostis stolonifera L.) fairways and greens on golf courses in the northeastern USA. Simulations produced 100-yr daily records of water runoff, pesticide runoff, and pesticide concentration in runoff for three locations: Boston, MA, Philadelphia, PA, and Rochester, NY. Results were summarized as annual and monthly means and annual maximum daily loads (AMDLs) corresponding to 10- and 20-yr return periods. Mean annual pesticide runoff loads did not exceed 3% of annual applications for any pesticide or site, and most losses were substantially less than 1% of application. However, annual or monthly mean concentrations of chlorothalonil, iprodione, and PCNB in fairway runoff often exceeded concentrations that result in 50% mortality of the affected species (LC50) for aquatic organisms. Concentrations of azoxystrobin, bensulide, cyfluthrin, and trichlorfon in extreme (1 in 10 yr or 1 in 20 yr) events often approached or exceeded LC50 levels. Concentrations of halofenozide, mancozeb, MCPP, oxadiazon, propiconazole, thiophanate-methyl, triadimefon, and trinexapac-ethyl were well below LC50 levels, and turf runoff of these chemicals does not appear to be hazardous to aquatic life in surface waters.


Assuntos
Modelos Teóricos , Praguicidas/análise , Poluentes da Água/análise , Agrostis , Animais , Monitoramento Ambiental , Golfe , Dose Letal Mediana , Medição de Risco , Movimentos da Água
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