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1.
Microbiol Spectr ; 10(5): e0189922, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36197290

RESUMO

Maintaining the health of seafarers is a difficult task during long-term voyages. Little is known about the corresponding changes in the gut microbiome-host interaction. This study recruited 30 seafarers undertaking a 6-month voyage and analyzed their gut microbiota using 16S rRNA gene sequencing. Fecal untargeted metabolomics analysis was performed using liquid chromatography-mass spectrometry. Significant changes in the composition of the gut microbiota and an increased ratio of Firmicutes/Bacteroidetes at the end (day 180) of the 6-month voyage, relative to the start (day 0), were observed. At the genus level, the abundances of Holdemanella and Plesiomonas were significantly increased, while the abundance of Bacteroides was decreased. Predicted microbial functional analysis revealed significant decreases in folate biosynthesis and biotin metabolism. Furthermore, 20 differential metabolites within six differentially enriched human metabolic pathways (including arginine biosynthesis, lysine degradation, phenylalanine metabolism, sphingolipid metabolism, pentose and glucuronate interconversions, and glycine, serine, and threonine metabolism) were identified by comparing the fecal metabolites at day 0 and day 180. Spearman correlation analysis revealed close relationships between the 14 differential microbiota members and the six differential fecal metabolites that might affect specific human metabolic pathways. This study adopted a multi-omics approach and provides potential targets for maintaining the health of seafarers during long-term voyages. These findings are worthy of more in-depth exploration in future studies. IMPORTANCE Maintaining the health of seafarers undertaking long-term voyages is a difficult task. Apart from the alterations in the gut microbiome and fecal metabolites after a long-term voyage, our study also revealed that 20 differential metabolites within six differentially enriched human metabolic pathways are worthy of attention. Moreover, we found close relationships between the 14 differential microbiota members and the six differential fecal metabolites that might impact specific human metabolic pathways. Accordingly, preventative measures, such as adjusting the gut microbiota by decreasing potential pathobionts or increasing potential probiotics as well as offsetting the decrease in B vitamins and beneficial metabolites (e.g., d-glucuronic acid and citrulline) via dietary adjustment or nutritional supplements, might improve the health of seafarers during long-term sea voyages. These findings provide valuable clues about gut microbiome-host interactions and propose potential targets for maintaining the health of seafarers engaged in long-term sea voyages.


Assuntos
Microbioma Gastrointestinal , Complexo Vitamínico B , Humanos , Microbioma Gastrointestinal/genética , RNA Ribossômico 16S/genética , Complexo Vitamínico B/análise , Citrulina/análise , Biotina , Lisina/análise , Metabolômica/métodos , Fezes , Pentoses/análise , Glucuronatos/análise , Glicina/análise , Ácido Glucurônico , Serina/análise , Fenilalanina/análise , Esfingolipídeos/análise , Treonina/análise , Arginina/análise , Ácido Fólico/análise
2.
Molecules ; 25(11)2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32481691

RESUMO

Nitrogen-rich adulterants in protein powders present sensitivity challenges to conventional combustion methods of protein determination which can be overcome by near Infrared spectroscopy (NIRS). NIRS is a rapid analytical method with high sensitivity and non-invasive advantages. This study developed robust models using benchtop and handheld spectrometers to predict low concentrations of urea, glycine, taurine, and melamine in whey protein powder (WPP). Effectiveness of scanning samples through optical glass and polyethylene bags was also tested for the handheld NIRS. WPP was adulterated up to six concentration levels from 0.5% to 3% w/w. The two spectrometers were used to obtain three datasets of 819 diffuse reflectance spectra each that were pretreated before linear discriminant analysis (LDA) and regression (PLSR). Pretreatment was effective and revealed important absorption bands that could be correlated with the chemical properties of the mixtures. Benchtop NIR spectrometer showed the best results in LDA and PLSR but handheld NIR spectrometers showed comparatively good results. There were high prediction accuracies and low errors attesting to the robustness of the developed PLSR models using independent test set validation. Both the plastic bag and optical glass gave good results with accuracies depending on the adulterant of interest and can be used for field applications.


Assuntos
Nitrogênio/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Proteínas do Soro do Leite/análise , Contaminação de Alimentos/análise , Glicina/análise , Reprodutibilidade dos Testes , Taurina/análise , Triazinas/análise , Ureia/análise
3.
Food Chem ; 307: 125534, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31644980

RESUMO

There has been increasing recent concern about the agricultural use of organophosphorus pesticides. A rapid and sensitive fluorescence assay for the detection of three organophosphorus pesticides has therefore been developed using 6-carboxy-fluorescein labeling aptamer as the probe and functionalized magnetic nanoparticles as the separation carrier. The aptamer hybridized with complementary DNA conjugated on the surface of the magnetic nanoparticles to form a magnetic aptamer-complementary DNA complex. Upon introducing the target organophosphorus pesticide, the aptamer departed from the complementary DNA, resulting in the fluorescence signal. Under optimized conditions, the limits of detection (LODs, S/N = 3) for trichlorfon, glyphosate, and malathion were 72.20 ng L-1, 88.80 ng L-1, and 195.37 ng L-1, respectively. The method was applied for the detection of trichlorfon, glyphosate, and malathion in spiked lettuce and carrot samples. The recoveries were in the range of 79.4%-118.7%, which were in good agreement with those obtained by gas chromatography, and the relative standard deviations were also acceptable. The method therefore has high sensitivity, so provides a means for the detection of multiple organophosphorus pesticides.


Assuntos
Aptâmeros de Nucleotídeos/química , Nanopartículas , Compostos Organofosforados/análise , Praguicidas/análise , Espectrometria de Fluorescência , Cromatografia Gasosa , Daucus carota/química , Corantes Fluorescentes , Glicina/análogos & derivados , Glicina/análise , Lactuca/química , Limite de Detecção , Magnetismo , Malation/análise , Praguicidas/química , Triclorfon/análise , Glifosato
4.
J Trace Elem Med Biol ; 56: 207-212, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31541895

RESUMO

Traceability of metal-glycinate-sulphate complexes (Metal-GLY) in feed requires specific analysis to differentiate complexes from inorganic forms. A previously described method focused on the quantification of Metal-GLY at one single concentration but not on the quantification of free metal ion forms. The objective of this work was to extend the method to quantify both Metal-GLY and free metal ion forms of various metals at low inclusion levels. A 50/50 w/w mix of corn flour and soybean meal was used as feed. Copper-glycinate(Cu-GLY), Manganese-glycinate (Mn-GLY) and Zinc-glycinate (Zn-GLY) complexes (provided by Pancosma SA) were used for in-feed inclusions. The feed metal background concentrations and species repartitions were assessed. Cu-GLY was spiked on feed at levels matching 5, 15 and 45 mg/kg, corresponding to metal concentrations of 1.2, 3.6 and 10.8 mg/kg. Mn-GLY and Zn-GLY were spiked at 15, 45 and 100 mg/kg, corresponding to 3.3, 9.9, 22 mg/kg Mn and 3.9, 11.7, 26mg/kg Zn, respectively. The water soluble fraction of un-supplemented feed contained 0.06 mg/kg Cu, 0.05 mg/kg Mn and 0.12 mg/kg Zn, with 69.5% of Cu, 33.2% of Mn and 24.3% of Zn being present under free metal ions but 30.4% of Cu being present under Cu-GLY, 66.82% of Mn and 75.7% of Zn being present under Mn-GLY and Zn-GLY, respectively. The supplemented feeds at the 3 tested doses, from the lowest to the highest inclusion levels, contained in total respectively: 1.1, 3.05 and 9.06 mg/kg Cu; 2.99, 8.9 and 18.2 mg/kg Mn; 3.72, 10.9 and 23.4 mg/kg Zn. The M-GLY species recovered by analysis within the different supplemented feeds ranged from 76.26 to 89.32% for Cu-GLY, form 94.5 to 98.51% for Mn-GLY and from 76.05 to 98.96% for Zn-GLY. These results showed that CE-ICP-MS technique can be used to quantify low doses and to measure metal-species repartition between Metal-GLY and free metal ions, when included in feeds. For the first time, this study highlighted that the raw materials used contain Metal-GLY compounds. This raises the question of the occurrence of these compounds within the different raw materials used in feed production that could dramatically affect the way to supplement minerals in animal feed.


Assuntos
Ração Animal/análise , Complexos de Coordenação/análise , Eletroforese Capilar/métodos , Glicina/análise , Metais/análise , Espectrofotometria Atômica/métodos , Sulfatos/análise , Animais
5.
J Sci Food Agric ; 99(15): 6911-6921, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31393604

RESUMO

BACKGROUND: This study aimed to evaluate the possibility of cotton waste enrichment with glycine betaine (GB) for production of two strains (P9, P10) of king oyster (Pleurotus eryngii). Cotton waste was used as (100%) control (T0 = cotton waste) and augmented with various combinations of GB, (T1 = 2 mmol L-1 , T2 = 4 mmol L-1 , T3 = 6 mmol L-1 , T4 = 8 mmol L-1 and T5 = 10 mmol L-1 ). The response of king oyster to GB was evaluated by earliness, yield, biological efficiency (BE), minerals (nitrogen, phosphorus, potassium, zinc (Zn), copper (Cu), magnesium (Mg), manganese (Mn), iron (Fe), sodium (Na), calcium (Ca)), total sugars, total soluble solids, reducing sugars, non-reducing sugars, ascorbic acid, proximate (crude protein, carbohydrates, crude fibers, ash, fats) content of fruiting body and Fourier-transform infrared (FTIR) spectroscopy analysis compared with the control substrate (cotton waste). RESULTS: The earliness, yield, and BE were higher as compared to control substrate and increased with an augmentation in the concentration of GB within the cotton waste. Two strains showed (on dry weight basis) 33.9-54.9 mg g-1 nitrogen, 6.8-12.5 mg g-1 phosphorus, 16.9-25.1 mg g-1 potassium, 40.5-64.2 mg kg-1 Zn, 17.1-37.3 mg kg-1 Cu, 1174-1325 mg kg-1 Mg, 20.1-29.1 mg kg-1 Mn, 129-265 mg kg-1 Fe, 779-835 mg kg-1 Ca), 6.3%-11.3% total sugars, 7.3-14.9 °Brix total soluble solids, 2.1-7.3% reducing sugars, 10.4-18.1% crude protein, 3.6-4.4% crude fiber and 5.6-16.7 mg (100 g)-1 on various concentration of GB enrich cotton waste. Cotton waste enriched with GB significantly affected nutritional profile of king oyster mushroom. CONCLUSION: The results revealed that GB enriched cotton waste can be used as an innovative substrate to enhance the yield and quality of king oyster mushroom. © 2019 Society of Chemical Industry.


Assuntos
Betaína/metabolismo , Meios de Cultura/metabolismo , Glicina/metabolismo , Gossypium/microbiologia , Pleurotus/química , Pleurotus/metabolismo , Resíduos/análise , Betaína/análise , Meios de Cultura/química , Glicina/análise , Gossypium/metabolismo , Minerais/metabolismo , Nitrogênio/análise , Nitrogênio/metabolismo , Fósforo/análise , Fósforo/metabolismo , Pleurotus/genética , Pleurotus/crescimento & desenvolvimento
6.
Artigo em Inglês | MEDLINE | ID: mdl-31287383

RESUMO

A method has been developed for the rapid, specific, accurate, precise and sensitive determination of glufosinate, glyphosate and its major metabolite, aminomethylphosphonic acid, in edible oils, by liquid chromatography coupled to tandem mass spectrometry. Oils were extracted with acidified water (1% formic acid), and the extracts were directly injected into an LC using a Hypercarb column as the stationary phase. The analytes were eluted by a mobile phase of methanol and water containing 1% acetic acid, and they were ionised by electrospray ionisation in negative ion mode. The method was validated and limits of quantification ranged from 5 µg kg-1 (aminomethylphosphonic acid) to 10 µg kg-1 (glyphosate and glufosinate). Three concentrations (10, 50 and 100 µg kg-1) were selected to perform recovery studies. Mean recoveries ranged from 81.4% to 119.4%. Intra and inter-day precision were lower than 19%. Different edible oils were analysed, and no residues of the studied herbicides were detected above limits of quantification.


Assuntos
Aminobutiratos/análise , Análise de Alimentos , Contaminação de Alimentos/análise , Glicina/análogos & derivados , Isoxazóis/análise , Óleos de Plantas/análise , Espectrometria de Massas em Tandem , Tetrazóis/análise , Aminobutiratos/metabolismo , Cromatografia Líquida , Glicina/análise , Glicina/metabolismo , Isoxazóis/metabolismo , Óleos de Plantas/metabolismo , Tetrazóis/metabolismo , Glifosato
7.
J Nutr ; 149(7): 1122-1132, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31162587

RESUMO

BACKGROUND: The minimum to which dietary crude protein (CP) level for broiler chickens can be reduced without decreasing growth and the glycine equivalent (Glyequi) concentration required are not known. The plasma metabolome might reflect dietary influences on physiological processes. OBJECTIVE: The aim of this study was to investigate the effect of 3 low CP levels with 4 Glyequi concentrations on growth and characteristics of nitrogen excretion, and to identify plasma metabolome variations. METHODS: Male Ross308 broiler chickens were provided 1 of 12 dietary treatments in 84 metabolism cages (10/cage) from days 7 to 21. Three diets with 163 (CP163), 147 (CP147), and 132 (CP132) g CP/kg were formulated, each containing 12, 15, 18, and 21 g Glyequi/kg. Essential amino acid concentrations were the same in all diets. Animals and feed were weighed on days 7 and 21 to determine average daily gain (ADG) and gain:feed ratio (G:F). Excreta were collected from days 18 to 21 to analyze nitrogenous components, and blood was obtained on day 21 to conduct a metabolome analysis. RESULTS: Two-factor ANOVA showed significant interaction effects for ADG, G:F, and nitrogen efficiency (P < 0.001). Reduction of CP decreased ADG and G:F, and increased nitrogen efficiency. Glyequi supplementation increased ADG (by 7.9 g/d) and G:F (by 0.07 g/g) at CP132. The ADG (by 2.4 g/d) at CP147 and G:F (by 0.02 g/g) at CP147 and CP163 increased up to 15 g Glyequi/kg. Multivariate statistical analysis showed an influence of Glyequi on plasma acylcarnitine and lysophosphatidylcholine concentrations, and a decrease of plasma phosphatidylcholine and sphingomyelin concentrations with reduced CP. CONCLUSIONS: These results suggest that a nutrient other than Glyequi limited growth when CP was reduced from CP163 to CP147, and that the response of broiler chickens to Glyequi is dependent on the dietary CP level. Plasma metabolites indicate dietary influences on the physiological state of the animals.


Assuntos
Ração Animal/análise , Galinhas/crescimento & desenvolvimento , Galinhas/metabolismo , Proteínas Alimentares/administração & dosagem , Glicina/análise , Metaboloma , Nitrogênio/urina , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas/sangue , Masculino
8.
J Chromatogr A ; 1601: 357-364, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31104848

RESUMO

Glyphosate, a widely used herbicide, has been classified as probably carcinogenic to humans by the International Agency for Research on Cancer (IARC). In the present study a method based on Field-Amplified Sample Injection and Sweeping Micellar Electrokinetic Chromatography (FASI sweep-MEKC) has been developed and validated for determination of glyphosate and its microbial metabolite aminomethylphosphonic acid (AMPA) in wheat flour. The method involved a preliminary solid phase extraction for cleanup of the aqueous extracts from wheat flour, based sequentially on C18 and strong anion exchange cartridges, followed by derivatization using 9-fluorenylmethylchloroformate. Optimization of sample cleanup and derivatization procedure was carried out by a HPLC-UV method, whereas FASI sweep-MEKC was applied for achieving the sensitivity necessary for analysis of real samples. To this regard, optimum conditions involved the use of an extended path fused-silica capillary (80 cm total length, 50 µm, i.d.) filled with a high concentration buffer (sodium phosphate 100 mM, pH 2.2). Electrokinetic sampling was carried out at -10 kV with injection time of 700 s and the separation of the loaded analytes was performed under MEKC conditions using sodium phosphate buffer 50 mM at pH 2.2, supplemented with sodium dodecyl sulfate, 100 mM. The method was validated for linearity, precision, accuracy and sensitivity, showing that using conventional UV detection (210 nm) the achieved limit of quantitation (LOQ) values for both the analytes were widely lower than those set by Authorities. In particular, LOQ for glyphosate and AMPA were found to be 5 and 2.5 ng/mL, respectively, corresponding to 0.1 and 0.05 mg/kg, in wheat flour. The method, applied to commercially available real samples (wheat flour from different manufacturers) and to an experimental sample obtained by cv. Svevo wheat, can be considered as a convenient alternative to the existing approaches in analysis of complex matrices.


Assuntos
Cromatografia Capilar Eletrocinética Micelar , Glicina/análogos & derivados , Compostos Organofosforados/análise , Triticum/química , Glicina/análise , Isoxazóis , Dodecilsulfato de Sódio , Extração em Fase Sólida , Tetrazóis , Água/química , Glifosato
9.
Environ Monit Assess ; 191(4): 244, 2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30915586

RESUMO

Glyphosate (GLP, N-(phosphonomethyl)glycine) is the most important broadband herbicide in the world, but discussions are controversial regarding its environmental behaviour and distribution. Residue analyses in a variety of environmental samples are commonly conducted by HPLC-MS where GLP needs to be derivatised with 9-fluoromethoxycarnonyl chloride (FMOC-Cl). Since this derivatisation reaction was suspected to be inhibited by metal ions in the sample matrix, the present study provides a comprehensive experimental study of the effect of metal ions (Al3+, Ca2+, Cd2+, Co2+, Cu2+, Fe2+, Fe3+, Mg2+, Mn2+, Zn2+) on derivatisation and GLP recovery. Results show that some metals (Cd2+, Co2+, Cu2+, Mn2+ and Zn2+) decreased the GLP recovery down to 19 to 59%. Complementary, quantum chemical modelling of 1:1 GLP-metal complexes as well as their reactivity with respect to FMOC-Cl was performed. Here, a decrease in reactivity of FMOC-Cl towards GLP-metal complexes is observed; i.e. the reaction is non-spontaneous in contrast to the free GLP case. The present results are in accord with previous studies and provide an explanation that full GLP recovery in different matrices was never reached. Remedy strategies to compensate for the inhibition effect are explored such as pH adjustment to acidic or alkaline conditions or addition of ethylenediaminetetraacetic acid (EDTA). In general, our results question the use of internal isotopic labelled standards (ILS) since this presupposes the presence of the analyte and the ILS in the same (free) form.


Assuntos
Monitoramento Ambiental/métodos , Glicina/análogos & derivados , Herbicidas/análise , Metais/química , Ácido Edético/química , Fluorenos/química , Glicina/análise , Íons , Modelos Químicos , Glifosato
10.
J Agric Food Chem ; 67(7): 2061-2065, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30694061

RESUMO

Glyphosate is a widely used herbicide in commercial crop production for both conventional and herbicide-resistant crops. Herbicide-resistant crops, like glyphosate-resistant sugar beet, are often exposed to multiple applications of glyphosate during the growing season. The fate of this herbicide in resistant crops has not been publicly documented. We investigated the fate of glyphosate and main metabolite aminomethylphosphonic acid in glyphosate-resistant sugar beet grown in northern Colorado. Glyphosate residues were measured via directed ultra-high-performance liquid chromatography tandem mass spectrometry analysis of sugar beet shoots and roots throughout the growing season, from samples collected at various steps during sugar beet processing, and from flow-through samples of greenhouse-grown beets. Sugar beet rapidly absorbed glyphosate after foliar application, and subsequently translocated the herbicide to its roots, with between 2 and 3 µg/g fresh weight measured in both tissue types within 1 week of application. However, only trace amounts of glyphosate remained in either the shoots or the roots 2 weeks after application. Analysis of irrigation flow-through in pot assays confirmed that the herbicide readily exuded out of the roots. Processing of the beets removed glyphosate and herbicide levels were below the limit of detection in the crystalline sugar final product.


Assuntos
Beta vulgaris/química , Beta vulgaris/crescimento & desenvolvimento , Manipulação de Alimentos/métodos , Glicina/análogos & derivados , Resistência a Herbicidas , Beta vulgaris/efeitos dos fármacos , Contaminação de Alimentos/análise , Contaminação de Alimentos/prevenção & controle , Glicina/administração & dosagem , Glicina/análise , Resíduos de Praguicidas/análise , Raízes de Plantas/química , Brotos de Planta/química , Glifosato
11.
Environ Int ; 124: 284-293, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30660841

RESUMO

One consequence of the intensive use of glyphosate is the contamination of rivers by the active substance and its metabolites aminomethyl phosphonic acid (AMPA) and sarcosine, inducing river eutrophication. Biofilms are the predominant lifestyle for microorganisms in rivers, providing pivotal roles in ecosystem functioning and pollutant removal. The persistence of glyphosate in these ecosystems is suspected to be mostly influenced by microbial biodegradation processes. The present study aimed to investigate the tripartite relationship among biofilms, phosphorus and glyphosate in rivers. The first part consists of a co-occurrence analysis among glyphosate, AMPA and phosphorus using an extensive dataset of measurements (n = 56,198) from French surface waters between 2013 and 2017. The second part investigated the capacity of natural river biofilms to dissipate glyphosate, depending on phosphorus availability and the exposure history of the biofilm, in a microcosm study. A strong co-occurrence among glyphosate, AMPA and phosphorus was found in surface waters. More than two-thirds of samples contained phosphorous with glyphosate, AMPA or both compounds. Seasonal fluctuations in glyphosate, AMPA and phosphorus concentrations were correlated, peaking in spring/summer shortly after pesticide spreading. Laboratory experiments revealed that natural river biofilms can degrade glyphosate. However, phosphorus availability negatively influenced the biodegradation of glyphosate and induced the accumulation of AMPA in water. An increase in alkaline phosphatase activity and phosphorus uptake was observed in glyphosate-degrading biofilms, evidencing the tight link between phosphorus limitation and glyphosate degradation by biofilms. The results of the present study show that phosphorus not only is a key driver of river eutrophication but also can reduce complete glyphosate degradation by biofilms and favour the accumulation of AMPA in river water. The predominant role of biofilms and the trophic status of rivers must therefore be considered in order to better assess the fate and persistence of glyphosate.


Assuntos
Biofilmes , Monitoramento Ambiental , Glicina/análogos & derivados , Rios/química , Poluentes Químicos da Água/análise , Biodegradação Ambiental , Monitoramento Ambiental/métodos , Glicina/análise , Compostos Organofosforados/análise , Fósforo/análise , Sarcosina/análise , Estações do Ano , Glifosato
12.
J Neurosurg ; 132(1): 239-251, 2019 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-30611141

RESUMO

OBJECTIVE: Motor cortex stimulation (MCS) is a neurosurgical technique used to treat patients with refractory neuropathic pain syndromes. MCS activates the periaqueductal gray (PAG) matter, which is one of the major centers of the descending pain inhibitory system. However, the neurochemical mechanisms in the PAG that underlie the analgesic effect of MCS have not yet been described. The main goal of this study was to investigate the neurochemical mechanisms involved in the analgesic effect induced by MCS in neuropathic pain. Specifically, we investigated the release of γ-aminobutyric acid (GABA), glycine, and glutamate in the PAG and performed pharmacological antagonism experiments to validate of our findings. METHODS: Male Wistar rats with surgically induced chronic constriction of the sciatic nerve, along with sham-operated rats and naive rats, were implanted with both unilateral transdural electrodes in the motor cortex and a microdialysis guide cannula in the PAG and subjected to MCS. The MCS was delivered in single 15-minute sessions. Neurotransmitter release was evaluated in the PAG before, during, and after MCS. Quantification of the neurotransmitters GABA, glycine, and glutamate was performed using a high-performance liquid chromatography system. The mechanical nociceptive threshold was evaluated initially, on the 14th day following the surgery, and during the MCS. In another group of neuropathic rats, once the analgesic effect after MCS was confirmed by the mechanical nociceptive test, rats were microinjected with saline or a glycine antagonist (strychnine), a GABA antagonist (bicuculline), or a combination of glycine and GABA antagonists (strychnine+bicuculline) and reevaluated for the mechanical nociceptive threshold during MCS. RESULTS: MCS reversed the hyperalgesia induced by peripheral neuropathy in the rats with chronic sciatic nerve constriction and induced a significant increase in the glycine and GABA levels in the PAG in comparison with the naive and sham-treated rats. The glutamate levels remained stable under all conditions. The antagonism of glycine, GABA, and the combination of glycine and GABA reversed the MCS-induced analgesia. CONCLUSIONS: These results suggest that the neurotransmitters glycine and GABA released in the PAG may be involved in the analgesia induced by cortical stimulation in animals with neuropathic pain. Further investigation of the mechanisms involved in MCS-induced analgesia may contribute to clinical improvements for the treatment of persistent neuropathic pain syndromes.


Assuntos
Analgesia/métodos , Estimulação Encefálica Profunda , Glicina/fisiologia , Córtex Motor/fisiopatologia , Neuralgia/terapia , Substância Cinzenta Periaquedutal/fisiopatologia , Ciática/terapia , Ácido gama-Aminobutírico/fisiologia , Animais , Bicuculina/administração & dosagem , Bicuculina/toxicidade , Vias Eferentes/efeitos dos fármacos , Vias Eferentes/fisiologia , Antagonistas GABAérgicos/administração & dosagem , Antagonistas GABAérgicos/toxicidade , Ácido Glutâmico/análise , Glicina/análise , Glicina/antagonistas & inibidores , Glicina/uso terapêutico , Hiperalgesia/tratamento farmacológico , Hiperalgesia/fisiopatologia , Hiperalgesia/terapia , Masculino , Microdiálise , Microinjeções , Neuralgia/tratamento farmacológico , Neuralgia/fisiopatologia , Limiar da Dor , Substância Cinzenta Periaquedutal/efeitos dos fármacos , Ratos , Ratos Wistar , Nervo Isquiático/lesões , Ciática/tratamento farmacológico , Ciática/fisiopatologia , Estricnina/administração & dosagem , Estricnina/toxicidade , Ácido gama-Aminobutírico/análise , Ácido gama-Aminobutírico/uso terapêutico
13.
Se Pu ; 36(9): 873-879, 2018 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-30251515

RESUMO

A method has been developed for the determination of glyphosate (GLY), glufosinate (GLUF), and the main metabolite aminomethylphosphonic acid (AMPA) residues in dry tea based on ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) coupled with pre-column derivatization. A systematic study of the effects of pretreatment methods including extraction and purification procedures was designed and carried out for the determination of GLY, GLUF, and AMPA. The results indicated that the optimal pretreatment method was as follows:the tea sample was first extracted by water in vortex, and then purified by a cation exchange solid-phase extraction column with the elution of 0.5% (v/v) formic acid aqueous solution. Finally, the eluant was derivatized by 9-fluorenylmethyl chloroformate, and the target compounds were separated on a C18 chromatographic column and analysed by UPLC-MS/MS (ESI+). GLY, GLUF, and AMPA showed good linearity in the range of 1-100 µ g/L, with correlation coefficients above 0.991. The limits of detection and limits of quantification were found to be 0.0160-0.0300 mg/kg and 0.0530-0.100 mg/kg, respectively. The average spiked recoveries of GLY, GLUF, and AMPA varied from 78.3% to 108% at three spiked levels (0.0500, 0.400, and 1.20 mg/kg), while the relative standard deviations ranged from 5.46% to 9.63%. The proposed method was utilized to detect 837 batches of tea samples. The detection ratios of GLY, GLUF, and AMPA were 3.46%, 0.24%, and 4.42%, respectively, while 0.24% of the investigated tea samples had values above maximum residue limits. The developed method is simple, rapid, sensitive, and accurate for the determination of GLY, GLUF, and AMPA in dry tea and may be used for routine analysis.


Assuntos
Aminobutiratos/análise , Glicina/análogos & derivados , Isoxazóis/análise , Chá/química , Tetrazóis/análise , Cromatografia Líquida de Alta Pressão , Fluorenos , Glicina/análise , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Glifosato
14.
J Agric Food Chem ; 66(38): 9952-9959, 2018 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-30173511

RESUMO

This study aimed to investigate the effects of creatine monohydrate (CMH) and guanidinoacetic acid (GAA) supplementation on the growth performance, meat quality, and creatine metabolism of finishing pigs. The pigs were randomly allocated to three treatment groups: the control group, CMH group, and GAA group. In comparison to the control group, CMH treatment increased average daily feed intake and GAA treatment increased average daily feed intake and average daily gain of pigs. In addition, CMH and GAA treatment increased pH45 min, myofibrillar protein solubility, and calpain 1 mRNA expression level and decreased the drip loss and shear force value in longissimus dorsi or semitendinosus muscle. Moreover, CMH and GAA supplementation increased the concentrations of creatine and phosphocreatine and the mRNA expressions of guanidinoacetate N-methyltransferase and creatine transporter in longissimus dorsi muscle, semitendinosus muscle, liver, or kidneys and decreased the mRNA expressions of arginine:glycine amidinotransferase in kidneys. In conclusion, CMH and GAA supplementation could improve the growth performance and meat quality and alter creatine metabolism of finishing pigs.


Assuntos
Ração Animal/análise , Creatina/metabolismo , Glicina/análogos & derivados , Carne/análise , Suínos/metabolismo , Animais , Calpaína/genética , Calpaína/metabolismo , Creatina/análise , Suplementos Nutricionais , Glicina/análise , Glicina/metabolismo , Rim/metabolismo , Fígado/metabolismo , Músculos/metabolismo , Suínos/genética , Suínos/crescimento & desenvolvimento
15.
Nutr Res ; 56: 79-89, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30055777

RESUMO

The oxidized/reduced state of plasma albumin in rats is influenced by the quantity of dietary protein. However, the effects of the protein quality on the oxidized/reduced state of plasma albumin are not clear. We hypothesized that the quality of dietary protein might modulate the oxidized/reduced state of plasma albumin. The aim of the present study was to examine whether the amino acid composition of dietary protein modulates the oxidized/reduced state of plasma albumin in rats. Male Sprague-Dawley rats were fed low-protein diets containing 5% casein (CA), 5% egg white (EW), or 6% wheat gluten (WG) for 2 weeks. The plasma albumin concentration gradually decreased in rats fed each diet; however, there was no significant difference among the groups. In rats fed the 5% CA diet, the percentage of mercaptalbumin within the total plasma albumin was significantly lower than in those fed the EW or WG diet. Compared with EW or WG, CA contains lower amounts of glycine and cystine. In rats fed a 5% CA diet supplemented with cystine, the percentage of mercaptalbumin was significantly higher than that in rats fed a 5% CA diet supplemented with glycine. The expression of hepatic eukaryotic initiation factor 4E-binding protein 1 was significantly lower in rats fed the cystine-supplemented diet than in those fed the glycine-supplemented diet. These results suggest that dietary protein with a high cystine content maintains plasma mercaptalbumin levels in rats fed low-protein diets.


Assuntos
Cistina/farmacologia , Dieta com Restrição de Proteínas , Proteínas Alimentares/farmacologia , Suplementos Nutricionais , Necessidades Nutricionais , Albumina Sérica/metabolismo , Animais , Proteínas de Transporte/metabolismo , Caseínas/química , Cistina/análise , Proteínas Alimentares/química , Clara de Ovo/química , Glutens/química , Glicina/análise , Peptídeos e Proteínas de Sinalização Intracelular , Fígado/efeitos dos fármacos , Masculino , Fosfoproteínas/metabolismo , Ratos Sprague-Dawley , Triticum/química
16.
Environ Sci Pollut Res Int ; 25(24): 24368-24378, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29948720

RESUMO

Glyphosate and glufosinate ammonium are the active ingredients of commonly used herbicides. Active agricultural lands extend over a large part of the Veneto region (Eastern Po Valley, Italy) and glyphosate and glufosinate ammonium are widely used. Consequently, surface waters can be potentially contaminated. This study investigates the occurrence of glyphosate and glufosinate ammonium as well as aminomethylphosphonic acid (AMPA, the degradation product of glyphosate) in river water of Veneto. Eighty-six samples were collected in 2015 at multiple sampling points across the region. Samples were analyzed for the two target herbicides, AMPA as well as for other variables, including water temperature, pH, dissolved oxygen, conductivity, hardness, BOD, COD, inorganic ions, total nitrogen, total phosphorus, total suspended solids, arsenic, and lead. The average concentrations (all samples) were 0.17, 0.18, and 0.10 µg L-1 for glyphosate, AMPA, and glufosinate ammonium, respectively. The European upper tolerable level for pesticides (annual average 0.1 µg L-1) was often exceeded. Chemometric analysis was therefore applied to (i) investigate the relationships among water pollutants, (ii) detect the potential sources of water contamination, (iii) assess the effective water pollution of rivers by identifying river basins with anomalous pollution levels, and (iv) assess the spatial variability of detected sources. Factor analysis identified four factors interpreted as potential sources and processes (use of herbicides, leaching of fertilizers, urban/industrial discharges, and the biological activity on polluted or stagnant waters). A discriminant analysis revealed that the pollution from anthropogenic discharges is homogeneously present in surface water of Veneto, while biological activity and fertilizers present heterogeneous distributions. This study gives insights into the concentrations of herbicides in rivers flowing through a wide region that has heavy use of these chemicals in agriculture. The study also points out some hot-spots and suggests the future implementation of the current monitoring protocols and network.


Assuntos
Aminobutiratos/análise , Glicina/análogos & derivados , Herbicidas/análise , Isoxazóis/análise , Tetrazóis/análise , Poluentes Químicos da Água/análise , Arsênio/análise , Análise da Demanda Biológica de Oxigênio , Monitoramento Ambiental/métodos , Glicina/análise , Concentração de Íons de Hidrogênio , Itália , Chumbo/análise , Compostos Organofosforados , Fósforo/análise , Rios/química , Estações do Ano , Glifosato
17.
Anal Chim Acta ; 1028: 96-103, 2018 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-29884358

RESUMO

The biosynthesis of creatine (Cr) is closely related to the bioavailability of guanidinoacetate (GAA). The lack of one or the other may compromise their role in the energy transport and cell signaling. A reliable estimate of their levels in biological samples is imperative since they are important markers of many metabolic disorders. Therefore, a new LC-MS/MS method for simultaneous determination and quantification of GAA and Cr by multiple reaction monitoring (MRM) mode was developed based on the hydrophilic interaction chromatography (HILIC) and response surface methodology (RSM) for the optimization of chromatographic parameters. The optimized parameters ensured good separation of these similar, very polar molecules (chromatographic resolution > 1.5) without prior derivatization step in a short analysis run (6 min). The developed method was validated to ensure accurate (R, 75.1-101.6%), precise (RSD < 20%) and low quantification (LOQ of 0.025 µg mL-1 for GAA and 0.006 µg mL-1 for Cr) of the tested analytes and the use of matrix-matched calibration eliminated variable effects of complex matrices such as human plasma and urine. Therefore, this method can be implemented in medical laboratories as a tool for the diagnostics of creatine deficiencies and monitoring of guanidinoacetate and creatine supplementation regimes in biological samples.


Assuntos
Cromatografia Líquida/métodos , Creatina/análise , Glicina/análogos & derivados , Interações Hidrofóbicas e Hidrofílicas , Espectrometria de Massas em Tandem/métodos , Calibragem , Creatina/sangue , Creatina/urina , Glicina/análise , Glicina/sangue , Glicina/urina , Humanos , Limite de Detecção , Reprodutibilidade dos Testes , Fatores de Tempo
18.
J Chromatogr A ; 1549: 31-38, 2018 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-29588098

RESUMO

A reliable and sensitive method was developed for simultaneous determination of glyphosate and glufosinate in various food products by liquid chromatography-tandem mass spectrometry. Based on extraction, derivatization with 9-fluorenylmethylchloroformate and purification on solid phase extraction column, quantification was done by using isotopic-labeled analytes as internal standard and calibration in matrix. Good selectivity and sensitivity were achieved with a limit of quantification of 5 µg/kg. The recoveries of these two pesticides ranged from 91% to 114% with inter-day and relative standard deviation of 3.8-6.1% in five matrices of cereal group spiked at 5, 10, and 20 µg/kg. An accuracy profile was performed for method validation, demonstrating the accuracy and precision of the method for the studied food groups. The verification results in expanded food groups indicated extensive applicability for the analysis of glyphosate and glufosinate. Finally, the developed method was applied to analyze 136 food samples including milk-based baby foods from the French Agency for Food, Environmental and Occupational Health & Safety. Glyphosate residues were detected in two breakfast cereal samples (6.0 and 34 µg/kg). Glufosinate residues were found in a sample of boiled potatoes (9.8 µg/kg). No residues were detected in the other samples, including milk-based baby foods with limits of detection ranging from 1 to 2 µg/kg. The method has been applied for routine national monitoring of glyphosate and glufosinate in various foods.


Assuntos
Aminobutiratos/análise , Cromatografia Líquida/métodos , Análise de Alimentos/métodos , Glicina/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Animais , Grão Comestível/química , Glicina/análise , Alimentos Infantis/análise , Limite de Detecção , Leite/química , Reprodutibilidade dos Testes , Solanum tuberosum/química , Extração em Fase Sólida , Solventes , Glifosato
19.
J Sep Sci ; 41(3): 740-746, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29152857

RESUMO

Traditional Chinese herbal medicine has long enjoyed the reputation of the world's most advanced system of natural medicine. Pinellia ternata is one of the most commonly used herbs in the traditional Chinese medical science. In this study, five representative ingredients of Pinellia ternata guanosine, methionine, glycine, 3,4-dihydroxybenzaldehyde, and homogentisic acid, were assayed using simple derivatization procedures. Under optimized experimental condition, five analytes in Pinellia ternata were rapidly separated and detected using microchip electrophoresis, affording the benefits of speed, minimal sample requirements, and sensitive on-the-chip electrochemical detection, in 5 min with linearity over a concentration of 20-500 µM (R2  = 0.994) with nearly complete recovery (95.6-98.5%).


Assuntos
Medicamentos de Ervas Chinesas/análise , Eletroforese em Microchip , Pinellia/química , Benzaldeídos/análise , Soluções Tampão , Catecóis/análise , Eletroforese , Glicina/análise , Guanosina/análise , Ácido Homogentísico/análise , Concentração de Íons de Hidrogênio , Modelos Lineares , Metionina/análise , Análise de Sequência com Séries de Oligonucleotídeos
20.
Zhongguo Zhong Yao Za Zhi ; 42(4): 739-745, 2017 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-28959846

RESUMO

This study aimed to analyze the analgesic effect and related central mechanisms of CQ prescription on cancer invasion induced mirror image pain (CIIMIP)in model mice.In the study, male BALB/c mice were randomly divided into normal group, operation control group (injected with 0.2 mL inactivated S180 sarcoma cell sap), model group (injected with 0.2 mL S180 sarcoma cell sap on the right leg near the greater trochanter of femur) and CQ prescription low dose group (intraperitoneally injected with CQ prescription 100 mg•kg⁻¹ on the basis of model mice), CQ prescription middle dose group (intraperitoneally injected with CQ prescription 150 mg•kg⁻¹ on the basis of model mice), and CQ prescription high dose group (intraperitoneally injected with CQ prescription 200 mg•kg⁻¹ on the basis of model mice). Mechanical withdraw threshold (MWT) of the mirror image lateral hind paws were evaluated by Von Frey hairs before modeling and after surgery. The levels of glutamate (Glu), gamma aminobutyric acid (GABA), glycine (Gly), and taurine (Tau) in the L3-L5 spinal cord were measured by the high performance liquid chromatography-fluorescence detector (HPLC-FLD); AimPlex detection technology with multiple factors was used to detect the levels of regulated on activation in normal T-cell expressed and secreted (RANTES), monocyte chemoattractant protein (MCP-3) in the L3-L5 spinal cord. Then we observed the influence of GABAa receptor antagonist (Bicuculline) on analgesic effect of CQ prescription.The results indicated that CQ prescription could remarkably increase MWT of model mice(P<0.01, P<0.05), decrease the level of Glu(P<0.01, P<0.05), improve the levels of GABA, Gly, Tau(P<0.01, P<0.05), lower the ratio of Glu/GABA(P<0.01, P<0.05), and reduce the levels of RANTES, MCP-3(P<0.05) in the L3-L5 spinal cord, and GABAa receptor antagonist significantly blocked the analgesic effect of CQ prescription at two time points(P<0.05).This study showed that CQ prescription had significant analgesic effect on CIIMIP model mice, and its mechanism was associated with regulating the balance between excitability amino acid(EAA) and inhibitory amino acid (IAA) transmitters in central nervous system, partially activating GABAa receptor, and reducing the release of RANTES and MCP-3 in the spinal cord.


Assuntos
Analgésicos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Neoplasias Experimentais/complicações , Dor/tratamento farmacológico , Animais , Ácido Glutâmico/análise , Glicina/análise , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Invasividade Neoplásica , Medula Espinal/química , Taurina/análise , Ácido gama-Aminobutírico/análise
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