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1.
J Clin Lab Anal ; 34(4): e23109, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31804000

RESUMO

BACKGROUND: The pulmonary surfactant especially lipids in amniotic fluid can reflect the development stage of fetal lung maturity (FLM). However, the conventional lecithin/sphingomyelin (L/S) ratio method by thin layer chromatography (TLC) is insufficient and inconvenient for FLM prediction in clinical practice. METHODS: The amniotic fluid samples were collected from the pregnant women in labor or undergoing amniocentesis and analyzed for its lipid contents with the liquid chromatography coupled with high-resolution mass spectrometry (LC-HRMS) method and the lamellar body count (LBC) method. To reveal the lipidomic profiling of different FLM stages, three groups of amniotic fluid samples including 8 from premature group (gestational week (GW) < 37), 10 from mature group (GW < 37), and 10 from mature group (GW > 38) were compared with the control group (n = 6) of 18 GWs separately. RESULTS: In the FLM prediction study, the sensitivity of the LC-HRMS method and LBC method was 91% and 73%, respectively; the specificity was 100% and 95%, respectively. The most significant metabolic pathway was linoleic acid metabolism between the premature group and the control group. Both glycerophospholipid metabolism and glycosylphosphatidylinositol-anchor biosynthesis were enriched in the mature groups. In search of potential FLM prediction markers in amniotic fluid, 8 phosphatidylcholines, 1 sphingomyelin, and 1 phosphatidylethanolamine were significantly increased in the mature groups compared with the premature group. CONCLUSION: An efficient LC-HRMS method for L/S ratio in predicting FLM was established. The linoleic acid metabolism may play an important role in the fetal lung development.


Assuntos
Líquido Amniótico/metabolismo , Maturidade dos Órgãos Fetais/fisiologia , Lipidômica/métodos , Pulmão/embriologia , Espectrometria de Massas/métodos , Amniocentese , Biomarcadores/análise , Cromatografia Líquida/métodos , Feminino , Humanos , Lecitinas/análise , Metabolismo dos Lipídeos , Gravidez , Reprodutibilidade dos Testes , Esfingomielinas/análise
2.
Analyst ; 144(16): 4826-4834, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31290490

RESUMO

This study demonstrates a unique strategy for enhancing infrared (IR) spectroscopic discrimination between gall bladder (GB) polyps and cancer. This strategy includes the separation of raw bile juice into three sections of organic, aqueous, and amphiphilic phases and a cooperative combination of all IR spectral features of each separated phase for the discrimination. Raw bile juice is viscous and complex in composition because it contains fatty acids, cholesterol, proteins, phospholipids, bilirubin, and other components; therefore, the acquisition of IR spectra providing more component-discernible information is fundamental for improving discrimination. For this purpose, raw bile juice was separated into an aqueous phase, mostly containing bile salts, an organic phase with isolated lipids, and an amphiphilic phase, mainly containing proteins. The subsequent IR spectra of each separated phase were mutually characteristic and complementary to each other. When all the IR spectral features were combined, the discrimination was improved compared to that using the spectra of raw bile juice with no separation. The cooperative integration of more component-specific spectra obtained from each separated phase enhanced the discrimination. In addition, the IR spectra of the major constituents in bile juice, such as bile acids, conjugated bile salts, lecithin, and cholesterol, were recorded to explain the IR features of each separated phase.


Assuntos
Bile/química , Neoplasias da Vesícula Biliar/diagnóstico , Pólipos/diagnóstico , Ácidos e Sais Biliares/análise , Colesterol/análise , Diagnóstico Diferencial , Vesícula Biliar , Humanos , Lecitinas/análise , Análise de Componente Principal , Espectrofotometria Infravermelho/métodos
3.
J Sci Food Agric ; 99(12): 5586-5593, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31152446

RESUMO

BACKGROUND: Mono-, di- and oligosaccharides, polyhydric alcohols and lipids are three main types of plasticizers used to process food materials. In the present study, inulin, maltitol and lecithin were selected as representative oligosaccharide, polyhydric alcohol and lipid fat replacers, respectively. Their effects on the physicochemical properties of reduced-fat mozzarella cheese were evaluated. RESULTS: Lecithin reduced the hardness and increased the degree of free oil released. Inulin and lecithin decreased the hydrophobic interaction of reduced-fat cheese. Maltitol improved the elasticity of the reduced-fat cheese and increased the hydrophobic interaction within the casein matrix. Maltitol-added cheese had a lower glass transition temperature (Tg ) than the other cheeses. Maltitol significantly improved the stretchability of the reduced-fat cheese. CONCLUSION: The results obtained in the present study suggest that maltitol is an effective fat replacer in reduced-fat mozzarella cheese and might enhance the cheese's functional properties. The Tg of cheese was related to the water and fat content, fat replacer addition and cross-linking degree of casein. The relationship between Tg and the physicochemical properties of cheese will be studied in further research. © 2019 Society of Chemical Industry.


Assuntos
Queijo/análise , Substitutos da Gordura/análise , Aditivos Alimentares/análise , Inulina/análise , Lecitinas/análise , Maltose/análogos & derivados , Plastificantes/análise , Álcoois Açúcares/análise , Animais , Caseínas/análise , Bovinos , Manipulação de Alimentos , Dureza , Maltose/análise
4.
AAPS PharmSciTech ; 20(3): 97, 2019 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-30694405

RESUMO

This work is devoted to design a novel nanostructured hybrid vesicle (NHV) made of lecithin and an acrylate/C10-C30 alkyl acrylate for the nasal delivery of a model active indomethacin (IND), and further to probe its microstructure, intermolecular interactions, drug release behavior, ex vivo permeation, and stability. NHVs were prepared by cavitation technology employing RSM-based central composite design (CCD). Amount of lecithin (X1), power of ultrasound (X2), and sonication time (X3) were selected as three independent variables while the studied response included Z-Avg (nm), polydispersity index (PDI), and zeta potential (mV). The designed system (NHV) was investigated through dynamic (DLS) and electrophoretic light scattering (ELS), attenuated total reflectance (ATR-FTIR), oscillatory measurement (stress and frequency sweep), and transmission electron microscopy (TEM). CCD was found useful in optimizing NHV. An optimized formulation (S6) had Z-Avg 80 nm, PDI 0.2, and zeta potential of - 43.26 mV. Morphology investigation revealed spherical vesicles with smaller TEM diameters (the largest particle being 52.26 nm). ATR analysis demonstrated significant intermolecular interactions among the drug (IND) and the components of vesicles. The designed vesicles had an elastic predominance and displayed supercase II (n > 1) type of drug release. Besides, the vesicles possessed potential to transport IND across the nasal mucosa with the steady-state flux (µg/cm2/h) and permeability coefficient (cm/h) of 26.61 and 13.30 × 10-3, respectively. NHV exhibited an exceptional stability involving a combination of electrostatic and steric interactions while the histopathology investigation confirmed their safety for nasal administration.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Indometacina/administração & dosagem , Administração Intranasal , Animais , Anti-Inflamatórios não Esteroides/química , Indometacina/química , Lecitinas/análise , Microscopia Eletrônica de Transmissão , Mucosa Nasal/metabolismo , Tamanho da Partícula , Permeabilidade , Ovinos , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
5.
Appl Environ Microbiol ; 83(8)2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28213539

RESUMO

Lecithin is a natural emulsifier used in a wide range of food and nonfood applications to improve physical stability, with no known bioactive effects. In this study, the effect of lecithin on the antimicrobial performance of a constant eugenol concentration was tested against three Escherichia coli strains (C600, 0.1229, and O157:H7 strain ATCC 700728). This is the first study, to our knowledge, focusing on lecithin at concentrations below those commonly used in foods to improve the stability of oil in water emulsions (≤10 mg/100 ml). For all three cultures, significant synergistic antimicrobial effects were observed when E. coli cultures were exposed to a constant eugenol concentration (ranging from 0.043 to 0.050% [wt/wt]) together with critical lecithin concentrations ranging from 0.5 to 1 mg/100 ml. Increasing the concentration of lecithin above 1 mg/100 ml (up to 10 mg/100 ml lecithin) diminished the antibacterial effect to values similar to those with eugenol-only treatments. The formation of aggregates (<100 nm) at the critical lecithin concentration was observed using cryo-transmission electron microscopy (cryo-TEM), together with a reduction in light absorbance at 284 nm. At critically low concentrations of lecithin, the formation of nanoscale aggregates is responsible for improving eugenol antimicrobial effects.IMPORTANCE Essential oils (EOs) are effective natural antimicrobials. However, their hydrophobicity and strong aromatic character limit the use of essential oils in food systems. Emulsifiers (e.g., lecithin) increase the stability of EOs in water-based systems but fail to consistently improve antimicrobial effects. We demonstrate that lecithin, within a narrow critical concentration window, can enhance the antimicrobial properties of eugenol. This study highlights the potential bioactivity of lecithin when utilized to effectively control foodborne pathogens.


Assuntos
Anti-Infecciosos/farmacologia , Escherichia coli O157/efeitos dos fármacos , Eugenol/farmacologia , Microbiologia de Alimentos , Lecitinas/análise , Contagem de Colônia Microbiana , Emulsões , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia
6.
J Dairy Sci ; 99(9): 6948-6960, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27344387

RESUMO

Whey protein phospholipid concentrate (WPPC) and delactosed permeate (DLP) are 2 coproducts of cheese whey processing that are currently underutilized. Past research has shown that WPPC and DLP can be used together as a functional dairy ingredient in foods such as ice cream, soup, and caramel. However, the scope of the research has been limited to a single WPPC supplier. The variability of the composition and functionality of WPPC was previously studied. The objective of this research was to expand on the previous study and examine the potential applications of WPPC and DLP blends in foods. In ice cream, WPPC was added as a natural emulsifier to replace synthetic emulsifiers. The WPPC decreased the amount of partially coalesced fat and increased the drip-through rate. In caramel, DLP and WPPC replaced sweetened condensed skim milk and lecithin. Cold flow increased significantly, and hardness and stickiness decreased. In cake, DLP and WPPC were added as a total replacement of eggs, with no change in yield, color, or texture. Overall, WPPC and DLP can be utilized as functional dairy ingredients at a lower cost in ice cream and cake but not in chewy caramel.


Assuntos
Laticínios/análise , Manipulação de Alimentos , Sorvetes/análise , Fosfolipídeos/análise , Proteínas do Soro do Leite/química , Animais , Queijo/análise , Colorimetria , Análise de Alimentos , Lecitinas/análise , Leite/química , Viscosidade
7.
Br J Nutr ; 113(12): 1835-43, 2015 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-25920593

RESUMO

To assess the effects of betaine on hepatic lipid accumulation and investigate the underlying mechanism, thirty-two male Sprague-Dawley rats weighing 100 (sd 2·50) g were divided into four groups, and started on one of four treatments: basal diet, basal diet with betaine administration, high-fat diet and high-fat diet with betaine administration. The results showed that no significant difference of body weight was found among experimental groups. Compared with high-fat diet-fed rats, a betaine supplementation decreased (P< 0·05) hepatic TAG accumulation induced by high-fat diet, which was also supported by hepatic histology results. Additionally, hepatic betaine-homocysteine methyltransferase concentration [corrected] as well as its mRNA abundance and lecithin level were found increased (P< 0·05) by betaine supplementation in both basal diet-fed rats and high-fat diet-fed rats. Betaine administration in high-fat diet-fed rats exhibited a higher (P< 0·05) concentration [corrected] of hepatic carnitine palmitoyltransferase 1 (CPT1) compared with high-fat diet-fed rats. High-fat diet inhibited (P< 0·05) the gene expression of hepatic PPARα and CPT1. However, betaine administration in high-fat diet-fed rats elevated (P< 0·05) the gene expression of PPARα and CPT1. Moreover, concentration, gene and protein expressions of hepatic fibroblast growth factor 21 (FGF21) were increased (P< 0·05) in response to betaine administration in high-fat diet group; meanwhile the gene expression of hepatic AMP-activated protein kinase was increased (P< 0·05) as well. The results suggest that betaine administration enhanced hepatic lipid export and fatty acid oxidation in high-fat diet-fed rats, thus effectively alleviating fat accumulation in the liver.


Assuntos
Betaína/administração & dosagem , Dieta Hiperlipídica , Ácidos Graxos/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Animais , Betaína-Homocisteína S-Metiltransferase/genética , Betaína-Homocisteína S-Metiltransferase/metabolismo , Peso Corporal/efeitos dos fármacos , Carnitina O-Palmitoiltransferase/genética , Carnitina O-Palmitoiltransferase/metabolismo , Dieta , Expressão Gênica/efeitos dos fármacos , Lecitinas/análise , Lipotrópicos , Fígado/efeitos dos fármacos , Masculino , Oxirredução , PPAR alfa/genética , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Triglicerídeos/metabolismo
8.
Talanta ; 275: 126062, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38615457

RESUMO

Neonatal respiratory distress syndrome (nRDS) is a challenging condition to diagnose which can lead to delays in receiving appropriate treatment. Mid infrared (IR) spectroscopy is capable of measuring the concentrations of two diagnostic nRDS biomarkers, lecithin (L) and sphingomyelin (S) with the potential for point of care (POC) diagnosis and monitoring. The effects of varying other lipid species present in lung surfactant on the mid IR spectra used to train machine learning models are explored. This study presents a lung lipid model of five lipids present in lung surfactant and varies each in a systematic approach to evaluate the ability of machine learning models to predict the lipid concentrations, the L/S ratio and to quantify the uncertainty in the predictions using the jackknife + -after-bootstrap and variant bootstrap methods. We establish the L/S ratio can be determined with an uncertainty of approximately ±0.3 mol/mol and we further identify the 5 most prominent wavenumbers associated with each machine learning model.


Assuntos
Biomarcadores , Recém-Nascido Prematuro , Aprendizado de Máquina , Síndrome do Desconforto Respiratório do Recém-Nascido , Espectrofotometria Infravermelho , Humanos , Síndrome do Desconforto Respiratório do Recém-Nascido/diagnóstico , Biomarcadores/análise , Espectrofotometria Infravermelho/métodos , Recém-Nascido , Esfingomielinas/análise , Surfactantes Pulmonares/análise , Surfactantes Pulmonares/química , Lecitinas/análise , Lecitinas/química , Lipídeos/análise , Lipídeos/química
9.
Lik Sprava ; (3-4): 14-8, 2012.
Artigo em Ucraniano | MEDLINE | ID: mdl-23356131

RESUMO

An evaluation of correlation between fatty acid composition in pulmonary surfactant lipids and 137Cs content in the body of children, residents of radiation-contaminated areas revealed that a increased incorporation of 137Cs promotes a disruption of fatty acid balance towards an increase in the saturation of the surfactant lipid complex, a destruction of lecithin fraction of surfactant, a decrease in antioxidant properties of surfactant system, an activation of lipid peroxidation processes in the respiratory area of lung by lipoxygenase type, a disturbance of polyunsaturated fatty acid metabolism on the stage of bioregulators-eicosanoid formation.


Assuntos
Radioisótopos de Césio/análise , Acidente Nuclear de Chernobyl , Ácidos Graxos Insaturados/análise , Ácidos Graxos/análise , Metabolismo dos Lipídeos/efeitos da radiação , Pulmão/efeitos da radiação , Surfactantes Pulmonares/efeitos da radiação , Criança , Eicosanoides/análise , Radiação Eletromagnética , Expiração , Ácidos Graxos/química , Ácidos Graxos Insaturados/química , Humanos , Lecitinas/análise , Peroxidação de Lipídeos/efeitos da radiação , Lipoxigenases/metabolismo , Pulmão/metabolismo , Surfactantes Pulmonares/química , Doses de Radiação , Radiometria , Ucrânia
10.
J Mass Spectrom ; 56(4): e4629, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32767454

RESUMO

A new atmospheric pressure ionization method, plasmaspray ionization, termed as PSI, was developed to be an alternative ambient ion source for mass spectrometry. It comprises a plasma jet device and a sample spray part. While the nonthermal plasma jet strikes the surface of stainless steel tube out of the spray capillary, the sprayed sample will be ionized with the assistant of auxiliary gas. Although PSI is a little bit more complex than electrospray ionization (ESI) in instrument, it shows both better linearity and higher sensitivity for organic compounds. For protein samples, it presents wider distributions of multiply charged ions and higher mass resolution without sacrificing any sensitivity. For the mechanism of PSI, the charge build-up process on the tip of capillary should play a key role for the ion formation, and the stimulated pulsed voltage on the flow tube will promote the ion aggregation speed until the charge density is high enough. PSI source contains the features of plasma ionization and ESI and can be considered as a novel combo bridging these techniques. These results reflect that this method of PSI can be applied and further developed as a versatile new ion source for a wild range of organic and biological samples.


Assuntos
Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Compostos Orgânicos/análise , Proteínas/análise , Ionização do Ar , Pressão Atmosférica , Cafeína/análise , Lecitinas/análise , Polímeros/análise , Propilenoglicóis/análise , Reserpina/análise
11.
Scand J Clin Lab Invest ; 70(5): 358-63, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20509824

RESUMO

OBJECTIVE: The detection of amniotic lamellar bodies (LB) has been shown to be a rapid and simple way to assess fetal lung maturity (FLM). The maturity thresholds for LB vary due to different factors, one being the type of particle-count analyser used. MATERIAL AND METHODS: The Sysmex XE-2100 hematological analyser was evaluated in determination of amniotic LB counts and compared with lecithin/sphingomyelin (L/S) and phosphatidylglycerol (PG) determination. We analysed 132 amniotic samples from a total of 109 mothers (71 diabetic) with 112 infants. Results. The correlation between the LB counts obtained with the Sysmex XE-2100 and our reference thin layer chromatography (TLC) phospholipid method was good. Samples with low L/S ratio (< or = 2.0) and no PG (i.e. premature fetal lung status), had low LB counts (n = 18, mean 8500/L, range 1000-26000), whereas 51 samples with mature fetal lung status had high LB counts (mean 63600/uL, range 20,000-139,000). In all our four cases of respiratory distress syndrome the LB counts were low (range 1000-28000/uL). The reference values for FLM determination were established: < or = 6000/microL for immature, values between 7000 and 35,000/uL for borderline results and >35,000/uL for mature. CONCLUSIONS. The amniotic LB count analysis with Sysmex XE-2100 has many advantages being a repeatable, inexpensive and quantitative method with a very short turn-around time. Consequently, our routine is to perform LB counts initially from all amniotic samples and only borderline LB results are analysed with TLC.


Assuntos
Líquido Amniótico/química , Maturidade dos Órgãos Fetais , Pulmão/embriologia , Complicações na Gravidez/fisiopatologia , Gravidez em Diabéticas/fisiopatologia , Surfactantes Pulmonares/análise , Adulto , Técnicas Citológicas/instrumentação , Feminino , Humanos , Recém-Nascido , Lecitinas/análise , Masculino , Fosfatidilgliceróis/análise , Gravidez , Síndrome do Desconforto Respiratório do Recém-Nascido/diagnóstico , Esfingomielinas/análise
12.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 41(2): 226-30, 2010 Mar.
Artigo em Zh | MEDLINE | ID: mdl-20506640

RESUMO

OBJECTIVE: To study the role and mechanism of antioxidants on inhibiting oxidative modification of high density lipoproteins (HDL). METHODS: Freshly prepared human plasma HDL was treated by incubation with copper ion, hyperchlorite or arterial wall cells. Compared to control, the test groups were treated with addition of different concentration of butylhydroxytoluene (BHT), vitamin C and vitamin E. Then, the relative electrophoretic mobility (REM), thiobarbituric acid-reactive substances (TBARS), ratio of lysolecithin to lecithin (LPC/PC), and lipoprotein moieties were investigated. RESULTS: BHT, vitamin C and vitamin E can significantly inhibit the increasing REM, TBARS, LPC/PC ratio and lipoprotein variation that induced by copper ion and hyperchlorite and arterial wall cells. But these antioxidants act on different manner. CONCLUSION: BHT, vitamin C and vitamin E can inhibit the oxidative modification of HDL and hence could be potential nutrients to prevent atherosclerosis.


Assuntos
Antioxidantes/farmacologia , Cobre/toxicidade , Lipoproteínas HDL/química , Lipoproteínas HDL/efeitos dos fármacos , Ácido Ascórbico/farmacologia , Hidroxitolueno Butilado/farmacologia , Humanos , Lecitinas/análise , Lisofosfatidilcolinas/análise , Oxirredução/efeitos dos fármacos , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Vitamina E/farmacologia
13.
Food Chem ; 314: 126173, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31954942

RESUMO

The detection of phospholipids oxidation is important for meat control and disease prevention. In this paper, a photoelectrochemical sensor based on printable mesoscopic chip (PMC) for fast and real-time monitoring phospholipids oxidation was designed and fabricated. TiO2, ZrO2 and carbon films of PMC were screen-printed onto the FTO glass layer by layer. The PMC and the feasibility for determination of phospholipids oxidation were investigated by scanning electron microscope (SEM), UV-vis spectroscopy, cyclic voltammograms (CVs) and electrochemical impedance spectroscopy (EIS), etc. The short circuit current (Jsc) was used as a signal current, which would decrease if phospholipids in PMC were undergoing oxidation for the change of electrical properties. Compared with other methods, phospholipids in PMC did not require pretreatment, and the process was nondestructive and real-time. Meanwhile, this method showed high sensitivity and good selectivity. The fabricating process of PMC is simple, and the costs are low, relatively.


Assuntos
Espectroscopia Dielétrica/instrumentação , Análise de Alimentos/instrumentação , Fosfolipídeos/análise , Carbono/química , Espectroscopia Dielétrica/métodos , Desenho de Equipamento , Análise de Alimentos/métodos , Lecitinas/análise , Lecitinas/química , Microscopia Eletrônica de Varredura , Oxirredução , Fosfolipídeos/química , Sensibilidade e Especificidade , Glycine max/química , Titânio/química
15.
Food Chem ; 279: 216-222, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30611483

RESUMO

The effects of amphiphilic compounds on the dielectric constant of bulk oils were determined and the utility of the dielectric constant as a reliable parameter for predicting the oxidative stability of edible oils was evaluated. As the content of monoacylglycerols (MAGs), lecithin, and moisture increased, the dielectric constant of modified corn oil increased at different rates, whereas the addition of free fatty acids, including oleic and linoleic acid, decreased the dielectric constant of modified corn oil. Unoxidized fresh bulk oils showed a wide range of dielectric constants, from 8 for canola oils to 33 for flaxseed oils. The dielectric constant showed a strong correlation with the percentage of unsaturated fatty acids in the bulk oils. Oils with low oxidative stability had a high dielectric constant. Overall, the dielectric constant of bulk oils is strongly correlated with the content of amphiphilic compounds, moisture content, and degree of unsaturation of fatty acids.


Assuntos
Ácidos Graxos não Esterificados/análise , Óleos de Plantas/química , Antioxidantes/química , Óleo de Milho/química , Ácidos Graxos não Esterificados/química , Lecitinas/análise , Lecitinas/química , Ácido Linoleico/análise , Ácido Linoleico/química , Óleo de Semente do Linho/química , Monoglicerídeos/análise , Monoglicerídeos/química , Oxirredução
16.
J Chromatogr A ; 1185(1): 71-7, 2008 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-18272158

RESUMO

Gel permeation chromatography (GPC) with attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectrometry detection has been proposed for the simultaneous determination of lecithin and soybean oil in dietary supplements. The method involves the extraction of analytes with dichloromethane in an ultrasound water bath and the injection of 2 ml of centrifuged and filtered extracts into the system integrated by two Envirogel GPC columns (19 mm x150 mm, 19 mm x 300 mm) coupled on-line. Dichloromethane was used as mobile phase. A method has been developed to select the most appropriated wavenumber to be used for the determination of each considered compound from the calculation of a factor which maximizes the analyte signal minimizing the interferent contributions, being selected the detection wavenumbers of 1034 and 1138 cm(-1) for lecithin and soybean oil, respectively in the first order derivative ATR-FTIR spectra. The method provides limits of detection of 2 and 4 mg ml(-1) for lecithin and soybean oil and repeatability values, measured as relative standard deviation, of 2.5% and 3.4% being extended the linear range till 100 mg ml(-1) for lecithin and up to 50 mg ml(-1) for soybean oil. Accurate results were found for 10 synthetic samples and 7 commercial dietary supplement preparations.


Assuntos
Cromatografia em Gel/métodos , Lecitinas/análise , Óleo de Soja/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Suplementos Nutricionais/análise , Análise de Fourier , Glycine max/química , Análise Espectral
17.
Early Hum Dev ; 84(7): 465-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18249076

RESUMO

BACKGROUND: Clinical studies suggest that respiratory outcome of infants born preterm may be influenced by placental insufficiency and hemolysis, elevated liver enzymes, low platelets (HELLP) syndrome. If so, one could expect to see differences in lung maturation indices (lecithin/sphingomyelin (L/S) ratio and lamellar body count (LBC)) in the amniotic fluid. The present study investigates lung maturation indices of preterm small for gestational age (SGA) fetuses with or without abnormal Doppler ultrasound examination and with or without maternal hypertension/HELLP syndrome. STUDY DESIGN: Retrospective cohort study of 76 neonates born in our center between 1997 and 2003 with gestational age (GA) <34 weeks, birth weight

Assuntos
Retardo do Crescimento Fetal/fisiopatologia , Maturidade dos Órgãos Fetais/fisiologia , Síndrome HELLP , Pulmão/embriologia , Insuficiência Placentária , Adolescente , Adulto , Líquido Amniótico/química , Líquido Amniótico/citologia , Estudos de Coortes , Feminino , Retardo do Crescimento Fetal/diagnóstico , Idade Gestacional , Síndrome HELLP/fisiopatologia , Indicadores Básicos de Saúde , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Lecitinas/análise , Pulmão/fisiologia , Insuficiência Placentária/fisiopatologia , Gravidez , Surfactantes Pulmonares/análise , Estudos Retrospectivos , Esfingomielinas/análise
18.
J Sep Sci ; 31(8): 1290-8, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18366026

RESUMO

The phosphatidylcholine (PC)-enriched fraction from soybean lecithin is of interest due to its critical role in both the pharmaceutical and industrial field. In this work, enhancement of the purity of the PC fraction along with other individual polar lipid fractions was achieved from crude soybean lecithin by using supercritical fluid extraction (SFE) with methanol-modified SC-CO(2). Neutral lipids were first removed from the crude sample using pure CO(2). Then, the effect of CO(2 )pressure, temperature, and modifier percentage on phospholipid (PL) fractionation from deoiled lecithin was compared with and without silica gel mixed with the lecithin. Pure fractions of phosphatidylethanolamine (PE) and PC were obtained by varying the modifier concentration of the extraction fluid at 460 atm and 40 degrees C with silica gel added to the deoiled lecithin. Without silica gel, coextraction of PE and PC was observed. A total of six components were isolated and tentatively identified in the extract of deoiled crude soybean lecithin.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Lecitinas/análise , Lecitinas/isolamento & purificação , Lipídeos/química , Lipídeos/isolamento & purificação , Adsorção , Dióxido de Carbono/química , Glicolipídeos/química , Lecitinas/química , Espectrometria de Massas/métodos , Metanol/química , Modelos Químicos , Fosfatidiletanolaminas/química , Pressão , Sílica Gel , Dióxido de Silício/química , Glycine max , Temperatura , Fatores de Tempo
19.
Chemosphere ; 71(6): 1115-26, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18078979

RESUMO

Among the tasks included in the "Quality and safety of feeding fats obtained from co-products or by-products of the food chain" Project, supported by the European Union and included in the 6th Framework Program, a number of fats and oils collected as co- or by-products from the food chain were selected for the determination of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and 'dioxin-like' polychlorinated biphenyls (DL-PCBs). In the majority of the cases these samples are currently employed as feed ingredients. Nevertheless, additional fats, which are forbidden for feedstuff purposes were also considered in this study. In general terms, fats and oils were classified taking into account their nature and the processes applied to obtain these co- or by-products. PCDD/F and DL-PCB levels were evaluated in a first group of samples composed of fish oils, animal fats and lecithins. As expected, fats and oils with an animal origin presented higher concentrations, expressed in pg WHO-TEQ/g, compared to the levels found in vegetable samples like lecithins. The category of fish oils had the highest values for both PCDD/Fs and the sum of PCDD/Fs and DL-PCBs, with some samples showing levels above the maximum established at the present legislation related to the presence of PCDD/Fs and DL-PCBs in animal feed [Commission Directive 2006/13/EC of 3 February 2006 amending Annexes I and II to Directive 2002/32/EC of the European Parliament and of the Council on undesirable substances in animal feed as regards dioxins and dioxin-like PCBs. Official Journal of the European Communities L32, 44-53]. In a second group, fats and oils with a more complex composition obtained from different transformation processes or even mixtures of fats were considered; thus, acid oils from chemical refining, acid oils from physical refining, recycled cooking oils, oils extracted from exhausted bleaching earths, hydrogenated by-products, fatty acids calcium soaps and miscellaneous fats were analyzed. The data revealed a significant variability in PCDD/F and DL-PCB levels, expressed in pg WHO-TEQ/g, in these products. It has to be pointed out that the analyses of fats and oils belonging to these categories of products were sometimes difficult due to the complexity of the samples. In terms of legislation most of these samples cannot be easily included into one of the specific categories of substances intended for feedstuff purposes that are regulated in Commission Directive 2006/13/EC.


Assuntos
Gorduras/química , Cadeia Alimentar , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análogos & derivados , Ração Animal/análise , Animais , Gorduras/metabolismo , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas , Lecitinas/análise , Dibenzodioxinas Policloradas/análise
20.
Am J Perinatol ; 25(8): 473-80, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18773379

RESUMO

We sought to define the risk of neonatal respiratory distress syndrome (RDS) as a function of both lecithin/sphingomyelin (L/S) ratio and gestational age. Amniotic fluid L/S ratio data were collected from consecutive women undergoing amniocentesis for fetal lung maturity at Yale-New Haven Hospital from January 1998 to December 2004. Women were included in the study if they delivered a live-born, singleton, nonanomalous infant within 72 hours of amniocentesis. The probability of RDS was modeled using multivariate logistic regression with L/S ratio and gestational age as predictors. A total of 210 mother-neonate pairs (8 RDS, 202 non-RDS) met criteria for analysis. Both gestational age and L/S ratio were independent predictors of RDS. A probability of RDS of 3% or less was noted at an L/S ratio cutoff of > or = 3.4 at 34 weeks, > or = 2.6 at 36 weeks, > or = 1.6 at 38 weeks, and > or = 1.2 at term. Under 34 weeks of gestation, the prevalence of RDS was so high that a probability of 3% or less was not observed by this model. These data describe a means of stratifying the probability of neonatal RDS using both gestational age and the L/S ratio and may aid in clinical decision making concerning the timing of delivery.


Assuntos
Líquido Amniótico/química , Idade Gestacional , Lecitinas/análise , Síndrome do Desconforto Respiratório do Recém-Nascido/epidemiologia , Esfingomielinas/análise , Humanos , Recém-Nascido , Modelos Logísticos , Medição de Risco
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