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1.
Food Chem ; 314: 126176, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31962282

RESUMO

Pasteurized donor human milk (PDHM) for preterm infant nutrition is fortified with hydrolyzates of cow's milk proteins, which have been poorly investigated in relation to heat-damage and occurrence of the bioactive peptides ß-casomorphins (BCMs). Therefore, thermal protein modifications of three commercial fortifiers were assessed by measuring well-recognized indexes of heat load. The fortifiers did not contain pyrraline, whereas furosine and lysinoalanine levels roughly overlapped the lowest values reported for liquid formulas addressed to term infant nutrition. Bovine BCMs 3 to 7 and human BCMs 3 to 9 were searched. Bovine BCMs 3, 4, 6 and 7 were found in the undigested fortifiers. Following in vitro digestion simulating the digestive conditions of premature infant, bovine BCMs still occurred in fortified PDHM; the human BCMs 3, 7, 8 and 9 formed. Overall, these results better address the nutritional features of protein fortifiers and fortified PDHM intended for nutrition of preterm infants.


Assuntos
Endorfinas/análise , Alimentos Fortificados , Proteínas do Leite/química , Leite Humano/química , Animais , Bovinos , Digestão , Endorfinas/química , Feminino , Alimentos Fortificados/análise , Temperatura Alta , Humanos , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Recém-Nascido Prematuro , Lisina/análogos & derivados , Lisina/análise , Lisinoalanina/análise , Norleucina/análogos & derivados , Norleucina/análise , Pasteurização , Pirróis/análise
2.
Food Chem ; 289: 328-339, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30955620

RESUMO

The changes in the bioactive phytochemicals of six cultivars of Thai germinated brown rice (GBR) were monitored in parallel to those of cold plasma-treated GBR (PGBR). After treatment with the optimal plasma conditions, the germination percentage, root length, and seedling height measurements of the most sensitive rice cultivar increased by 84%, 57%, and 69%, respectively. For all of the rice cultivars, there were no significant differences in the antioxidant activities of the GBRs and PGBRs. Conversely, higher contents of γ-oryzanols were observed in the PGBR group than in the GBR group during the 2-day germination period. Certain cultivars in the PGBR group reached their maximum values for total phenolic compounds, total vitamin E, certain simple phenolics, phytosterols, triterpenoids, and anthocyanins one day earlier than the same values for GBR. In contrast, the concentrations of 2-acetyl-1-pyrroline in both the GBR and PGBR samples were reduced significantly with increased germination time.


Assuntos
Oryza/química , Compostos Fitoquímicos/análise , Gases em Plasma , Antocianinas/análise , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Germinação , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Fenóis/análise , Compostos Fitoquímicos/química , Fitosteróis/análise , Extratos Vegetais/química , Pirróis/análise , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Espectrometria de Massas em Tandem , Tailândia
3.
J Agric Food Chem ; 67(10): 3046-3054, 2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30810038

RESUMO

2-Acetyl-1-pyrroline (2-AP) is a key odorant in many foods, such as aromatic rice and wheat bread, with a very low odor threshold of 0.05 µg/L in water. The small molecule with a popcornlike, roasty odor is generated biologically or by Strecker degradation within the Maillard-reaction cascades during thermal food processing with methylglyoxal and 1-pyrroline as the main direct precursors. Numerous gas-chromatographic methods for the analysis of 2-AP have been published, but the reactivity of the compound leads to discrimination or degradation during sample workup. We developed a novel derivatization method for 2-AP with o-phenylenediamine followed by HPLC-MS/MS analysis of the resulting stable quinoxaline. The precision (7%), repeatability (14%), recovery (92%), linearity (0.79-500 µg/kg), limit of detection (LOD, 0.26 µg/kg), and limit of quantitation (LOQ, 0.79 µg/kg) were validated for rice matrix and were excellent as compared with those of methods published before. With the novel method, 2-AP levels in typical foods like aromatic rice (131 µg/kg), wheat bread (18 µg/kg), brown bread (18 µg/kg), rye bread (18 µg/kg), and popcorn (38 µg/kg) were determined.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Odorantes/análise , Pirróis/análise , Espectrometria de Massas em Tandem/métodos , Pão/análise , Análise de Alimentos , Oryza/química , Triticum/química
4.
Food Chem Toxicol ; 123: 561-565, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30458269

RESUMO

Fludioxonil is a phenylpyrrole pesticide that is applied to fruit and vegetable crops post-harvest to minimize losses to mold, both during transport and at point of sale. Its effectiveness is reflected in the dramatic increase in its production/usage since its introduction in 1994, an increase that has peaked in recent years as it became licenced for use abroad. Recently, doubts as to the nature of its mechanism of action have been raised. Given that the pesticide has long been known to induce stress intermediates in target and non-target organisms alike, the lack of a firmly established mechanism might be cause for concern. Troubling reports further delineate a capacity to disrupt hepatic, endocrine and neurological systems, indicating that fludioxonil may represent a health threat to consumers. In the absence of a clear, safe mechanism of action, fludioxonil should be re-evaluated for its potential to impact human health.


Assuntos
Produtos Agrícolas/química , Dioxóis/efeitos adversos , Fungicidas Industriais/efeitos adversos , Pirróis/efeitos adversos , Qualidade de Produtos para o Consumidor , Dioxóis/análise , Contaminação de Alimentos/análise , Fungicidas Industriais/análise , Humanos , Pirróis/análise
5.
Mar Pollut Bull ; 136: 230-242, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30509803

RESUMO

Levels and profiles of naturally produced halogenated bipyrroles (Br4Cl2-DBP and Cl7-MBP), methoxylated tetrabromodiphenyl ethers (6-MeO-BDE47), anthropogenic perfluoroalkyl substances (PFASs) and legacy persistent organic pollutants (POPs) were investigated in the livers of 14 cetaceans from the Sea of Japan and the North Pacific Ocean. The concentrations of Br4Cl2-DBP (4 to 4900 ng/g-wet), Cl7-MBP (16 to 3960 ng/g-wet) and 6-MeO-BDE47 (7 to 190 ng/g-wet) were higher in the order of killer whales > toothed whales > baleen whales. Profiles of PFASs were dominated by perfluoroundecanoic and perfluorotridecanoic acids (10 to 540 ng/g-wet), sum of which accounted for 70% of total measured PFASs. Regional difference was observed for Cl7-MBP and PFASs, which were higher in the Sea of Japan, whereas Br4Cl2-DBP was in the North Pacific Ocean. Specific accumulation pattern of these natural contaminants in cetaceans around northern Japan could help compare the exposure profile of PFASs and POPs among other geographic regions.


Assuntos
Cetáceos , Hidrocarbonetos Halogenados/análise , Fígado/química , Poluentes Químicos da Água/análise , Animais , Monitoramento Ambiental , Feminino , Hidrocarbonetos Halogenados/química , Japão , Masculino , Oceano Pacífico , Pirróis/análise , Pirróis/química , Orca
6.
Pesqui. vet. bras ; 38(8): 1528-1536, Aug. 2018. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-976485

RESUMO

Bactérias do gênero Aeromonas são patógenos altamente disseminados no ambiente aquático, responsáveis por grandes perdas econômicas na piscicultura de diversos países. São micro-organismos oportunistas e sua patogenicidade está ligada a alguns fatores de virulência, como a formação de biofilme. O estresse salino é um dos fatores que favorecem a formação dessas colônias e, consequentemente, o aumento de infecções. Essas infecções quando estão associadas ao biofilme são ainda mais resistentes aos antimicrobianos. Nesse contexto, o polipirrol destaca-se como uma alternativa antimicrobiana por possuir vários atributos terapêuticos e não apresentar toxicidade aos organismos. Dessa forma, o objetivo desse estudo foi avaliar o perfil de susceptibilidade e a capacidade de formação de biofilme dos isolados de Aeromonas spp. associados aos diferentes níveis de salinidade e polipirrol. Determinou-se a atividade antibacteriana dos isolados e ensaios de motilidade foram realizados com bactérias que carreavam o gene fla. Também verificou-se a capacidade do cloreto de sódio e polipirrol em interferir na formação do biofilme. Os resultados foram evidenciados com a microscopia eletrônica de varredura. As concentrações de 2 e 3% de NaCl inibiram a motilidade bacteriana. Na formação do biofilme, 83% dos isolados bacterianos induziram a produção na concentração de 0,25%. O polipirrol causou a morte de todos os isolados testados na concentração de 125μg/mL. Além disso, esse composto diminuiu a motilidade bacteriana nas concentrações de 0,25 a 3%, sendo que em relação à produção de biofilme, não houve interferência. Esses resultados evidenciam que os diferentes níveis de NaCl influenciam na formação do biofilme favorecendo a persistência da infecção. Este estudo também realçou a potencialidade do polipirrol como agente bactericida, sendo uma alternativa eficaz às drogas antimicrobianas para o tratamento das infecções causadas por Aeromonas spp.(AU)


Bacteria of the genus Aeromonas are highly disseminated pathogens in the aquatic environment, responsible for great economic losses in the pisciculture of several countries. They are opportunistic microorganisms and their pathogenicity is linked to some virulence factors, such as biofilm formation. Saline stress is one of the factors that favor the formation of these colonies and, consequently, the increase of infections. These infections, when associated with biofilm, are even more resistant to antimicrobials. In this context, polypyrrole stands out as an antimicrobial alternative because it has several therapeutic attributes and does not present toxicity to organisms. Thus, the objective of this study was to evaluate the susceptibility profile and the biofilm formation capacity of Aeromonas spp. associated with different levels of salinity and polypyrrole. The antibacterial activity of the isolates was determined and motility assays were performed with bacteria bearing the fla gene. The ability of sodium chloride and polypyrrole to interfere with biofilm formation has also been demonstrated. The results were evidenced with scanning electron microscopy. Concentrations of 2 and 3% of NaCl inhibited bacterial motility. In the biofilm formation, 83% of the bacterial isolates induced production at the concentration of 0.25%. Polypyrrole caused the death of all the isolates tested at the concentration of 125μg/mL. In addition, this compound decreased bacterial motility at concentrations of 0.25 to 3%, and no biofilm was produced. These results show that the different levels of NaCl influence in the formation of the biofilm favoring the persistence of the infection. This study also highlighted the potential of polypyrrole as a bactericidal agent, being an effective alternative to antimicrobial drugs for the treatment of infections caused by Aeromonas spp.(AU)


Assuntos
Animais , Pirróis/análise , Biofilmes/classificação , Aeromonas , Aquicultura
7.
J Oleo Sci ; 67(7): 893-904, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29877224

RESUMO

Aroma intensities of rice are correlated with the mixture of aroma compounds it contains. 2-acetyl-1-pyrroline (2AP) has been reported as a major aroma compound and as a characteristic compound in fragrant rice. In this study, Thai local cultivars were classified into fragrant and non-fragrant rice based on the 2AP content and molecular characterization. Local rice cultivars were also examined for their proline content and volatile compounds profile, which are important factors in determining aroma. The results suggested that 43 Thai local rice cultivars were classified into 25 fragrant rice cultivars and 18 non-fragrant cultivars. The type of fragrant rice cultivars included 16 non-colored and 9 colored rice cultivars, while the type of non-fragrant rice cultivars included 14 non-colored and 4 colored rice cultivars. The proline content of local rice cultivars was determined and showed no correlation with the 2AP content; however, the proline level appears to be associated with the environmental stress in the rice cultivation area. One hundred and forty volatile compounds were identified from local rice cultivars. Among the detected compounds, 18 volatile compounds, including hexanal 1-pentanol octanal (E)-2-heptenal 6-methyl-5-hepten-2-one 1-hexanol nonanal 2-butoxy-ethanol (E)-2-octenal 1-tetradecene 1-octen-3-ol decanal benzaldehyde (E)-2-nonenal 1-nonanol benzyl alcohol isovanillin and vanillin contributed to the aroma intensities of both fragrant and non-fragrant rice. Aroma compounds were more abundant in fragrant than in non-fragrant rice. Moreover, the levels of aroma compounds recorded in non-colored cultivars were higher than those in colored rice cultivars. In contrast, the 2AP content of colored rice cultivars was higher than that in non-colored rice cultivars. Our findings may assist rice breeding programs in producing a new aromatic genotype rice with high potential aroma intensities.


Assuntos
Qualidade dos Alimentos , Odorantes/análise , Oryza/química , Pirróis/análise , Benzaldeídos/análise , Benzaldeídos/isolamento & purificação , Exposição Ambiental , Genótipo , Oryza/classificação , Oryza/genética , Tailândia
8.
Food Chem ; 265: 173-181, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29884369

RESUMO

A moisture-sensitive 2-acetyl-1-pyrroline zinc chloride complex (2AP-ZnCl2) was successfully encapsulated by spray-chilling, using a hydrophobic moisture barrier as a practical way to protect the complex and to help facilitate its general use in food applications. Use of octacosane as wall material provided a flavor retention of 65.3%. The results from scanning electron microscopy (SEM) and X-ray micro-computed tomography (X-ray micro-CT) indicated desirable morphological characteristics of the matrix type microcapsules. Gas chromatography (GC) and absorbance spectroscopy were used for chemical quantitation of 2AP and ZnCl2, respectively, in the microcapsules. Results revealed no degradation of 2AP occurred as a result of the encapsulation process. This study is the first to demonstrate the feasibility of producing high quality microcapsules from labile flavor complexes by spray-chilling. The use of generally recognized as safe (GRAS) substances, including 2AP and ZnCl2, may allow for widespread commercial use of 2AP as a flavor ingredient.


Assuntos
Cápsulas/química , Cloretos/química , Aromatizantes/química , Pirróis/química , Compostos de Zinco/química , Alcanos/química , Cápsulas/análise , Cloretos/análise , Cromatografia Gasosa , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Varredura , Pirróis/análise , Microtomografia por Raio-X , Compostos de Zinco/análise
9.
Talanta ; 185: 151-159, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29759182

RESUMO

The use of sorbate and nitrite in meat processing may lead to the formation of 2-methyl-1,4-dinitro-pyrrole (DNMP), a mutagenic compound. This work was aimed at developing and validating an analytical method for the quantitation of DNMP by liquid chromatography-tandem mass spectrometry. Full validation was performed in accordance to Commission Decision 2002/657/EC and method applicability was checked in several samples of meat products. A simple procedure, with low temperature partitioning solid-liquid extraction, was developed. The nitrosation during the extraction was monitored by the N-nitroso-DL-pipecolic acid content. Chromatographic separation was achieved in 8 min with di-isopropyl-3-aminopropyl silane bound to hydroxylated silica as stationary phase. Samples of bacon and cooked sausage yielded the highest concentrations of DNMP (68 ±â€¯3 and 50 ±â€¯3 µg kg-1, respectively). The developed method proved to be a reliable, selective, and sensitive tool for DNMP measurements in meat products.


Assuntos
Produtos da Carne/análise , Mutagênicos/análise , Pirróis/análise , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
10.
Food Res Int ; 106: 686-695, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29579975

RESUMO

The aroma of bread crust, as one of the first characteristics perceived, is essential for bread acceptance. However, gluten-free bread crusts exhibit weak aroma. A SPME-GC/QTOF methodology was optimised with PCA and RSM and validated for the quantification of 44 volatile compounds in bread crust, extracting 0.75 g of crust at 60 °C for 51 min. LODs ranged between 3.60 and 1760 µg Kg-1, all the R2 were higher than 0.99 and %RSD for precision and %Er for accuracy were lower than 9% and 12%, respectively. A commercial wheat bread crust was quantified, and furfural was the most abundant compound. Bread crusts of wheat starch and of japonica rice, basmati rice and teff flours were also quantified. Teff flour and wheat starch crusts were very suitable for improving gluten-free bread crust aroma, due to their similar content in 2-acetyl-1-pyrroline and 4-hydroxy-2,5-dimethyl-3(2H)-furanone compared to wheat flour crust and also for their high content in pyrazines.


Assuntos
Pão/análise , Dieta Livre de Glúten , Análise de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Olfato , Microextração em Fase Sólida , Compostos Orgânicos Voláteis/análise , Eragrostis/química , Farinha/análise , Análise de Alimentos/normas , Furanos/análise , Cromatografia Gasosa-Espectrometria de Massas/normas , Oryza/química , Pirróis/análise , Reprodutibilidade dos Testes , Microextração em Fase Sólida/normas , Amido/análise , Triticum/química
11.
Heredity (Edinb) ; 120(5): 422-436, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29472695

RESUMO

The silkworm cocoon colour has attracted researchers involved in genetics, physiology and ecology for a long time. 'Ryokuken' cocoons are yellowish green in colour due to unusual flavonoids, prolinylflavonols, while 'Sasamayu' cocoons are light green and contain only simple flavonol glucosides. We found a novel gene associated with the cocoon colour change resulting from a change in flavonoid composition and named it Lg (light green cocoon). In the middle silk glands of the + Lg /+ Lg larvae, 1-pyrroline-5-carboxylic acid (P5C) was found to accumulate due to a decrease in the activity of pyrroline-5-carboxylate reductase (P5CR), an enzyme reducing P5C to proline. Sequence analysis of BmP5CR1, the candidate gene for Lg, revealed a 1.9 kb insertion and a 4 bp deletion within the 1st intron, a 97 bp deletion within the 4th intron, and a > 300 bp insertion within the 3'-UTR, in addition to two amino acid changes on exons 3 and 4 in + Lg /+ Lg compared to Lg/Lg. Decreased expression of BmP5CR1 was observed in all of the investigated tissues, including the middle silk glands in + Lg /+ Lg , which was probably caused by structural changes in the intronic regions of BmP5CR1. Furthermore, a BmP5CR1 knockout strain exhibited a yellowish green cocoon with the formation of prolinylflavonols. These results indicate that the yellowish green cocoon is produced by a BmP5CR1 deficiency. To our knowledge, this is the first report showing that the defect of an enzyme associated with intermediate metabolism promotes the conjugation of phytochemicals derived from foods with endogenously accumulating metabolites in animal tissues.


Assuntos
Bombyx/enzimologia , Flavonoides/análise , Proteínas de Insetos/metabolismo , Oxirredutases/metabolismo , Pirróis/metabolismo , Animais , Bombyx/química , Bombyx/genética , Cor , Feminino , Flavonoides/metabolismo , Ligação Genética , Genótipo , Glucosídeos/metabolismo , Proteínas de Insetos/genética , Larva , Masculino , Oxirredutases/genética , Fenótipo , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/metabolismo , Pigmentação , Pirróis/análise , Seda/análise , Seda/metabolismo
12.
Bioelectrochemistry ; 121: 46-55, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29353096

RESUMO

The enhancement of bioelectrochemical properties of microorganism by in situ formation of conducting polymer within the cell structures (e.g. cell wall) was performed. The synthesis of polypyrrole (Ppy) within fungi (Aspergillus niger) cells was achieved. Two different Aspergillus niger strains were selected due to their ability to produce glucose oxidase, which initiated the Ppy formation through products of enzymatic reaction. The evolution of Ppy structural features was investigated by absorption spectroscopy, cyclic voltammetry and Fourier transform infrared spectroscopy.


Assuntos
Aspergillus niger/metabolismo , Polímeros/metabolismo , Pirróis/metabolismo , Aspergillus niger/química , Aspergillus niger/citologia , Vias Biossintéticas , Condutividade Elétrica , Proteínas Fúngicas/metabolismo , Glucose Oxidase/metabolismo , Polimerização , Polímeros/análise , Pirróis/análise
13.
J Pharm Biomed Anal ; 149: 133-142, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29112902

RESUMO

Vonoprazan fumarate is a novel potassium-competitive acid blocker for the treatment of acid-related diseases. In the present study, a simple, fast, and economic reversed-phase liquid chromatography (LC) method was developed for the analysis of ten related substances (raw materials, by-products and degradants) in vonoprazan fumarate. The optimized separation was performed on a Phenomenex Kinetex EVO C18 (250mm×4.6mm, 5.0µm) column. The mobile phase consisted of (A) 0.03M sodium phosphate buffer (pH adjusted to 6.5) - methanol - acetonitrile (72:25:3, v/v/v) and (B) 0.03M sodium phosphate buffer (pH adjusted to 6.5) - acetonitrile (30:70, v/v). Detection of the analytes was conducted at 230nm using a UV detector. The stability-indicating ability of this method was demonstrated by carrying out forced degradation studies. Vonoprazan underwent significant degradation when subjected to alkaline and oxidative stress conditions, while the drug proved to be stable to acidic, thermal and photolytic degradation. The degradants did not interfere with the detection of vonoprazan fumarate and its impurities. The performance of this method was validated in accordance to the regulatory guidelines recommended by the International Conference on Harmonisation (ICH) and this validation included specificity, linearity, limit of detection (LOD), limit of quantification (LOQ), accuracy, precision and robustness. The method proposed in this paper could be applied for process development as well as quality assurance of vonoprazan in bulk drug, since no monograph is available in official compendia.


Assuntos
Contaminação de Medicamentos/prevenção & controle , Fumaratos/análise , Inibidores da Bomba de Prótons/análise , Pirróis/análise , Sulfonamidas/análise , Tecnologia Farmacêutica/métodos , Química Farmacêutica/economia , Química Farmacêutica/instrumentação , Química Farmacêutica/métodos , Cromatografia Líquida de Alta Pressão/economia , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/economia , Cromatografia de Fase Reversa/instrumentação , Cromatografia de Fase Reversa/métodos , Análise Custo-Benefício , Estabilidade de Medicamentos , Fumaratos/química , Fumaratos/normas , Limite de Detecção , Oxirredução , Inibidores da Bomba de Prótons/química , Inibidores da Bomba de Prótons/normas , Pirróis/química , Pirróis/normas , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Sulfonamidas/química , Sulfonamidas/normas , Tecnologia Farmacêutica/economia , Tecnologia Farmacêutica/instrumentação , Tecnologia Farmacêutica/normas , Fatores de Tempo
14.
J Sci Food Agric ; 98(9): 3225-3233, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29280151

RESUMO

Pyrraline and pentosidine are advanced Maillard reaction products derived from the reaction of glucose with the lysine amino group on proteins. They have been implicated in uremia, diabetes, and related complications, including inflammation, retinopathy, and nephropathy. This review focuses on the formation mechanism, human potential risks, and detections of pentosidine and pyrraline and lays the foundation for further study of pentosidine and pyrraline. © 2017 Society of Chemical Industry.


Assuntos
Arginina/análogos & derivados , Análise de Alimentos , Lisina/análogos & derivados , Norleucina/análogos & derivados , Pirróis/efeitos adversos , Pirróis/análise , Arginina/efeitos adversos , Arginina/análise , Arginina/química , Reagentes para Ligações Cruzadas , Complicações do Diabetes/induzido quimicamente , Diabetes Mellitus/induzido quimicamente , Glucose/química , Produtos Finais de Glicação Avançada , Humanos , Inflamação/induzido quimicamente , Lisina/efeitos adversos , Lisina/análise , Lisina/química , Estrutura Molecular , Norleucina/efeitos adversos , Norleucina/análise , Norleucina/química , Pirróis/química , Fatores de Risco , Uremia/induzido quimicamente
15.
Magn Reson Med ; 79(2): 1010-1019, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28480589

RESUMO

PURPOSE: Genetically encoded reporters can assist in visualizing biological processes in live organisms and have been proposed for longitudinal and noninvasive tracking of therapeutic cells in deep tissue. Cells can be labeled in situ or ex vivo and followed in live subjects over time. Nevertheless, a major challenge for reporter systems is to identify the cell population that actually expresses an active reporter. METHODS: We have used a nucleoside analog, pyrrolo-2'-deoxycytidine, as an imaging probe for the putative reporter gene, Drosophila melanogaster 2'-deoxynucleoside kinase. Bioengineered cells were imaged in vivo in animal models of brain tumor and immunotherapy using chemical exchange saturation transfer MRI. The number of transduced cells was quantified by flow cytometry based on the optical properties of the probe. RESULTS: We performed a comparative analysis of six different cell lines and demonstrate utility in a mouse model of immunotherapy. The proposed technology can be used to quantify the number of labeled cells in a given region, and moreover is sensitive enough to detect less than 10,000 cells. CONCLUSION: This unique technology that enables efficient selection of labeled cells followed by in vivo monitoring with both optical and MRI. Magn Reson Med 79:1010-1019, 2018. © 2017 International Society for Magnetic Resonance in Medicine.


Assuntos
Rastreamento de Células/métodos , Células Dendríticas/química , Genes Reporter/genética , Engenharia Genética/métodos , Imunoterapia/métodos , Imagem por Ressonância Magnética/métodos , Animais , Pesquisa Biomédica/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/terapia , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Desoxicitidina/análogos & derivados , Desoxicitidina/análise , Desoxicitidina/química , Desoxicitidina/metabolismo , Drosophila melanogaster/enzimologia , Drosophila melanogaster/genética , Citometria de Fluxo , Genes de Insetos/genética , Células HEK293 , Humanos , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/terapia , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Pirróis/análise , Pirróis/química , Pirróis/metabolismo
16.
AAPS PharmSciTech ; 19(1): 123-133, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28620763

RESUMO

Sunitinib malate (SM) is reported as a weakly soluble drug in water due to its poor dissolution rate and oral bioavailability. Hence, in the current study, various "self-nanoemulsifying drug delivery systems (SNEDDS)" of SM were prepared, characterized and evaluated for the enhancement of its in vitro dissolution rate and anticancer efficacy. On the basis of solubilization potential of SM in various excipients, "Lauroglycol-90 (oil), Triton-X100 (surfactant) and Transcutol-P (cosurfactant)" were selected for the preparation of SM SNEDDS. SM-loaded SNEDDS were developed by spontaneous emulsification method, characterized and evaluated for "thermodynamic stability, self-nanoemulsification efficiency, droplet size, polydispersity index (PDI), zeta potential (ZP), surface morphology, refractive index (RI), the percent of transmittance (% T) and drug release profile." In vitro dissolution rate of SM was significantly enhanced from an optimized SNEDDS in comparison with SM suspension. The optimized SNEDDS of SM with droplet size of 42.3 nm, PDI value of 0.174, ZP value of -36.4 mV, RI value of 1.339, % T value of 97.3%, and drug release profile of 95.4% (after 24 h via dialysis membrane) was selected for in vitro anticancer efficacy in human colon cancer cells (HT-29) by MTT assay. MTT assay indicated significant anticancer efficacy of optimized SM SNEDDS against HT-29 cells in comparison with free SM. The results of this study showed the great potential of SNEDDS in the enhancement of in vitro dissolution rate and anticancer efficacy of poorly soluble drug such as SM.


Assuntos
Antineoplásicos/análise , Indóis/análise , Pirróis/análise , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Emulsões , Excipientes , Células HT29 , Humanos , Indóis/química , Indóis/uso terapêutico , Nanopartículas , Pirróis/química , Pirróis/uso terapêutico , Diálise Renal , Solubilidade , Sunitinibe , Tensoativos , Suspensões
17.
Sci Total Environ ; 616-617: 554-563, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29149719

RESUMO

This study investigated accumulation of perfluoroalkyl substances (PFASs), persistent organochlorines (OCs), and naturally produced halogenated compounds (NHCs), including brominated methylbipyrroles and methoxylated bromodiphenyl ethers, in liver, blood, and blubber from Dall's porpoises (Phocoenoides dalli) and harbor porpoises (Phocoena phocoena) stranded in Hokkaido, northern Japan. Profiles of the PFASs were dominated by perfluoroundecanoic acid and perfluorotridecanoic acid, both of which accounted for 70% of the total measured PFAS concentrations in both porpoise species. The mean concentrations of the ∑PFCA were 573ng/g wet weight (ng/g-wet) in liver, 62ng/g-wet in whole blood, and 28ng/g-wet in blubber from the Dall's porpoises, and were significantly higher (p<0.05) than those in the harbor porpoises. The hepatic concentrations of perfluorooctane sulfonate (PFOS) were <14ng/g-wet, and accounted for only 3% of the total measured PFASs. The profiles of PFASs in the porpoises resembled those in fish species in this area, implying a common source of exposure to PFASs in East Asia. On the other hand, in the blubber of Dall's porpoises, NHCs were dominated by 2,3,3',4,4',5,5'-heptachloro-1'-methyl-1,2'-bipyrrole (867ng/g-wet), 5,5'-dichloro-1,1'-dimethyl-3,3',4,4'-tetrabromo-2,2'-bipyrrole (481ng/g-wet), and 6-methoxy-2,2',4,4'-tetrabromodiphenyl ether (30ng/g-wet), which were present at higher concentrations than in harbor porpoises. Factor analysis with varimax rotation revealed that factor 1 had higher eigenvectors (element in eigenvalues) for long-chain PFCAs and PFOS, which was found in the highest concentrations in the liver, whereas factor 2 was mainly associated with lipid soluble NHCs and OCs in both species. No correlations were observed between long-chain PFCAs and NHCs in the porpoises, probably because of the different sources and accumulation kinetics. Future research should assess the temporal trends and long-term effects of PFASs and NHCs in the tissues of mammals from the Asia-Pacific region.


Assuntos
Ácidos Carboxílicos/análise , Cadeia Alimentar , Phocoena , Toninhas , Pirróis/análise , Poluentes Químicos da Água/análise , Tecido Adiposo/química , Animais , Monitoramento Ambiental , Japão , Fígado/química
18.
Biomed Chromatogr ; 32(2)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28905410

RESUMO

A gas chromatography-tandem mass spectrometry method was developed and validated to simultaneously determine boscalid and fludioxonil in grape and soil samples. These samples were extracted with 10 mL of acetonitrile and purified using a mixed primary secondary amine/octadecylsilane sorbent. The method showed good linearity (R2 > 0.99) in the calibration range 0.005-2 µg/mL for both pesticides. The limits of detection and quantification for the two analytes in grape and soil were 0.006 and 0.02 mg/kg, respectively. Fungicide recoveries in grape and soil were 81.18-92.11% for boscalid and 82.73-97.67% for fludioxonil with relative standard deviations of 1.31-10.31%. The established method was successfully applied to the residual analysis of boscalid and fludioxonil in real grape and soil samples. The terminal residue concentrations of boscalid and fludioxonil in grape samples collected from Anhui and Guizhou were <5 mg/kg (the maximum residue limit set by China) 7 days after the last application and 1 mg/kg (the maximum residue limit set by USA) 14 days after the last application. These results could provide guidance for the proper and safe use of boscalid and fludioxonil in grape and help the Chinese government to establish an MRL for fludioxonil in grape.


Assuntos
Compostos de Bifenilo/análise , Dioxóis/análise , Fungicidas Industriais/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Niacinamida/análogos & derivados , Resíduos de Praguicidas/análise , Pirróis/análise , Solo/química , Vitis/química , Análise de Variância , Limite de Detecção , Modelos Lineares , Niacinamida/análise , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
19.
Sci Total Environ ; 610-611: 1222-1238, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28851143

RESUMO

Information from effects of pesticides in sediments at an ecosystem level, to validate current and proposed risk assessment procedures, is scarce. A sediment-spiked outdoor freshwater microcosm experiment was conducted with fludioxonil (lipophilic, non-systemic fungicide) to study exposure dynamics and treatment-related responses of benthic and pelagic macroinvertebrates and zooplankton. Besides blank control and solvent control systems the experiment had six different treatment levels (1.7-614mga.s./kg dry sediment) based around the reported 28-d No Observed Effect Concentration (NOEC) for Chironomus riparius (40mga.s./kg dry sediment). Twelve systems were available per treatment of which four were sacrificed on each of days 28, 56 and 84 after microcosm construction. Fludioxonil persisted in the sediment and mean measured concentrations were 53-82% of the initial concentration after 84days. The dissipation rate increased with the treatment level. Also exposure concentrations in overlying water were long-term, with highest concentrations 28days after initiation of the experiment. Sediment-dwelling Oligochaeta and pelagic Rotifera and Cladocera showed the most pronounced treatment-related declines. The most sensitive sediment-dwelling oligochaete was Dero digitata (population NOEC 14.2mga.s./kg dry sediment). The same NOEC was calculated for the sediment-dwelling macroinvertebrate community. The most sensitive zooplankton species was the cladoceran Diaphanosoma brachyurum (NOEC of 1.6µga.s./L in overlying water corresponding to 5.0mga.s./kg dry sediment). At the two highest treatments several rotifer taxa showed a pronounced decrease, while the zooplankton community-level NOEC was 5.6µga.s./L (corresponding to 14.2mga.s./kg dry sediment). Zooplankton taxa calanoid Copepoda and Daphnia gr. longispina showed a pronounced treatment-related increase (indirect effects). Consequently, an assessment factor of 10 to the chronic laboratory NOECs of Chironomus riparius (sediment) and Daphnia magna (water) results in a regulatory acceptable concentration that is sufficiently protective for both the sediment-dwelling and pelagic organisms in the microcosms.


Assuntos
Organismos Aquáticos/fisiologia , Dioxóis/toxicidade , Ecossistema , Fungicidas Industriais/toxicidade , Pirróis/toxicidade , Poluentes Químicos da Água/toxicidade , Zooplâncton/fisiologia , Animais , Chironomidae/fisiologia , Cladóceros/fisiologia , Copépodes/fisiologia , Daphnia/fisiologia , Dioxóis/análise , Água Doce , Fungicidas Industriais/análise , Sedimentos Geológicos/química , Oligoquetos/fisiologia , Fitoplâncton , Pirróis/análise , Rotíferos/fisiologia , Poluentes Químicos da Água/análise
20.
Drug Test Anal ; 10(4): 768-773, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28940782

RESUMO

Hair analysis for the assessment of alcohol or drug abstinence has become a routine procedure in forensic toxicology. Hair coloration leading to loss of incorporated xenobiotics and to false negative results has turned out to be a major problem. Currently only colored extracts provide hints of manipulations but not bleaching. A liquid chromatographic-tandem mass spectrometric (LC-MS/MS) method was developed and validated to determine 1H-pyrrole-2,3,5-tricarboxylic acid (PTCA), a major oxidation product of melanin. PTCA was determined in natural hair samples (n = 21) after treatment with 3% hydrogen peroxide (H2 O2 ) for 30 or 40 minutes with concentrations up to 12% for 40 minutes. In another series, 12 natural hair samples were submitted to different coloration procedures (henna, tinting, semi-permanent and permanent dyeing, bleaching) and the changes in PTCA content were determined. A significant increase in the PTCA content was found for both incubation times and increasing H2 O2 concentrations. Coloration with henna or tinting had no influence on PTCA levels detected, but a significant increase was observed after semi-permanent and permanent dyeing and bleaching. As PTCA concentrations in natural hair were found to be in a range of <2.1-16.4 ng/mg (8.4 ± 3.8 ng/mg, mean ± SD, n = 33), a cut-off of 20 ng/mg is recommended for the distinction between natural vs. excessively oxidized hair. In case of naturally low melanin content (light-blond or white hair), no marked increase in PTCA may occur. The present study demonstrated that PTCA is formed during oxidative treatment of melanin in hair, which can be used to detect previous hair coloration including oxidation.


Assuntos
Cabelo/química , Melaninas/análise , Pirróis/análise , Espectrometria de Massas em Tandem/métodos , Biomarcadores/análise , Cromatografia Líquida de Alta Pressão/métodos , Toxicologia Forense/métodos , Cabelo/efeitos dos fármacos , Cabelo/metabolismo , Preparações para Cabelo/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Melaninas/metabolismo , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Pirróis/metabolismo , Detecção do Abuso de Substâncias/métodos
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