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1.
Plant Sci ; 305: 110830, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33691964

ABSTRACT

PACLOBUTRAZOL RESISTANCE (PRE) genes code atypical HLH transcriptional regulators characterized by the absence of a DNA-binding domain but present an HLH dimerization domain. In vegetative tissues, the function of these HLH proteins has been related with cell elongation processes. In strawberry, three FaPRE genes are expressed, two of them (FaPRE2 and FaPRE3) in vegetative tissues while FaPRE1 is fruit receptacle-specific. Ubiquitous FaPRE1 accumulation produced elongated flower receptacles and plants due to the elongation of the main aerial vegetative organs, with the exception of leaves. Histological analysis clearly demonstrated that the observed phenotype was due to significant changes in the parenchymal cell's morphology. In addition, transcriptomic studies of the transgenic elongated flower receptacles allowed to identify a small group of differentially expressed genes that encode cell wall-modifying enzymes. Together, the data seem to indicate that, in the strawberry plant vegetative organs, FaPRE proteins could modulate the expression of genes related with the determination of the size and shape of the parenchymal cells.


Subject(s)
Cell Size , Fragaria/anatomy & histology , Fragaria/growth & development , Fragaria/genetics , Plant Leaves/anatomy & histology , Plant Leaves/growth & development , Plant Proteins/physiology , Crops, Agricultural/anatomy & histology , Crops, Agricultural/genetics , Crops, Agricultural/growth & development , Ectopic Gene Expression , Gene Expression Regulation, Plant , Genes, Plant , Plant Leaves/genetics , Plant Proteins/genetics , Spain
2.
Adv Food Nutr Res ; 81: 31-64, 2017.
Article in English | MEDLINE | ID: mdl-28317608

ABSTRACT

Food processing has been carried out since ancient times as a way to preserve and improve food nutritional and organoleptic properties. Although it has some undesirable consequences, such as the losses of some nutrients and the potential formation of toxic compounds, a wide range of benefits can be enumerated. Among them, the increased total antioxidant capacity of many processed foods has been known for long. This consequence has been related to both the release or increased availability of natural antioxidants and the de novo formation of substances with antioxidant properties as a consequence of the produced reactions. This review analyzes the chemical changes produced in foods during processing with special emphasis on the formation of antioxidants as a consequence of carbonyl-amine reactions produced by both carbohydrate- and lipid-derived reactive carbonyls. It discusses the lastest advances produced in the characterization of carbonyl-amine adducts and their potential action as primary (free radical scavengers), secondary (chelating and other ways to prevent lipid oxidation), and tertiary (carbonyl scavengers as a way to avoid lipid oxidation consequences) antioxidants. Moreover, the possibility of combining amino compounds with different hydrophobicity, such as aminophospholipids and proteins, with a wide array of reactive carbonyls points out to the use of carbonyl-amine reactions as a new way to induce the formation of a great variety of substances with antioxidant properties and very variable hydrophilia/lipophilia. All presented results point out to carbonyl-amine reactions as an effective method to generate efficacious antioxidants that can be used in food technology.


Subject(s)
Antioxidants , Food Analysis , Food Handling , Amines/chemistry , Amino Acids/chemistry , Lipids/chemistry
3.
Radiologia ; 56(5): e12-6, 2014.
Article in Spanish | MEDLINE | ID: mdl-22560236

ABSTRACT

Angiosarcoma is a rare mesenchymal neoplasm that may arise from vascular or lymphatic tissue. Bone primary angiosarcoma is extremely rare, representing less than 1% of all angiosarcomas. It́s a very aggressive neoplasm and patients have metastatic disease at initial diagnosis in a large percentage of cases. On radiographs, these lesions are usually aggressive osteolytic lesions, commonly with soft-tissue mass extension, and tumoral enhancement on CT or MR imaging. The appearance of the bone scan is variable, describing studies with tracer uptake or low uptake. These tumours are more often found in the long bones, but spinal involvement has been reported in 10% of patients. There are a few reports in the literature of bone angiosarcoma with lung metastases. We present a patient with multifocal epithelioid angiosarcoma (spine and ribs) and multiple lung metastasis, evidenced by CT and conventional bone scintigraphy, with a fast growth.


Subject(s)
Bone Neoplasms/pathology , Hemangiosarcoma/secondary , Lung Neoplasms/secondary , Adult , Hemangiosarcoma/pathology , Humans , Lung Neoplasms/pathology , Male
4.
Rev. neurol. (Ed. impr.) ; 48(9): 489-495, 1 mayo, 2009. tab, ilus
Article in Spanish | IBECS | ID: ibc-128102

ABSTRACT

Introducción. La gran mayoría de crisis epilépticas son breves y autolimitadas, pero, en ocasiones, su duración puede ser mayor de la esperada, lo que, en el caso de las crisis convulsivas generalizadas, comporta un alto riesgo de morbimortalidad, que aumenta con su duración. Esta gravedad justifica la realización de una guía de práctica clínica de consenso, basada en evidencias implícitas sobre aspectos relacionados con el manejo terapéutico recomendado a un paciente con una crisis prolongada asistido en los servicios de urgencias. Materiales y métodos. Se ha realizado una búsqueda selectiva de la información científica relacionada con el tema propuesto en Pubmed-Medline, utilizando filtros de evidencia científica. Dicha búsqueda se completó en otros buscadores de evidencia científica, como Tripdatabase, Biblioteca Cochrane Plus o DARE. Las referencias seleccionadas se analizaron y discutieron por los autores y se extrajeron las evidencias disponibles y las recomendaciones de ellas derivadas. Resultados. Se identificaron 33 documentos primarios y seis guías de práctica o protocolos relacionados con el tema propuesto. Las recomendaciones se insertaron en el texto de manera explícita. Conclusiones. El protocolo terapéutico debe iniciarse ante cualquier crisis convulsiva con una duración superior a cinco minutos, asegurando, en primer lugar, la correcta función respiratoria y cardiocirculatoria, y administrando fármacos antiepilépticos por vía intravenosa de acción rápida y con dosis altas, mantenidos hasta que se identifica y controla la causa. Las crisis no convulsivas prolongadas, por su menor morbimortalidad, no precisan generalmente de una terapia tan enérgica y con riesgo de complicaciones (AU)


Introduction. Most epileptic seizures are brief and self-limiting, but sometimes they can last longer than expected and this entails (in the case of generalised seizures) a high risk of morbidity and mortality, which increases as they get longer. This severity justifies the need to draw up a set of consensus-based practice guidelines based on implicit evidence, to use Liberati’s nomenclature, concerning aspects related to the recommended therapeutic management of a patient with prolonged seizures who is being attended in an emergency department. Materials and methods. A selective search was conducted on PubMed-Medline for scientific information related to the subject using scientific evidence filters. This search was completed in other scientific evidence search engines, such as Tripdatabase, Biblioteca Cochrane Plus or DARE. The selected references were analysed and discussed by the authors, and the available evidence and any recommendations that could be drawn from it were collected. Results. The search revealed the existence of 33 primary documents and six practice guidelines or protocols related with the topic under study. The recommendations were inserted in the text explicitly. Conclusions. The therapeutic protocol must be started when faced with any seizures that last more than five minutes. First, steps must be taken to ensure proper respiratory and cardiocirculatory functioning, and then fast-acting antiepileptic drugs are administered intravenously and in high doses until the cause is identified and controlled. Due to their lower level of morbidity and mortality, prolonged non-convulsive seizures do not generally require therapy that is so vigorous and with such a high risk of complications (AU)


Subject(s)
Humans , Status Epilepticus/drug therapy , Epilepsy/drug therapy , Anticonvulsants/therapeutic use , Seizures/drug therapy , Evidence-Based Practice , Clinical Protocols , Practice Patterns, Physicians'
5.
Nutr Hosp ; 22(4): 471-7, 2007.
Article in Spanish | MEDLINE | ID: mdl-17650888

ABSTRACT

The continuous increasing of overweight and obesity, among children and adolescents, constitutes an important public health problem. It is necessary to know and quantify this problem in order to delimit its magnitude and to identify the main risk groups. The enKid study (1998-2000) has estimated an obesity prevalence in Spain of 13,9% within the population group aged 2-22 years. Up to now, there was no data available about the city of Ceuta. In this study, it has been estimated an obesity prevalence of 8,75% among the Ceuta population group aged 6-13 years.


Subject(s)
Obesity/epidemiology , Adolescent , Child , Female , Global Health , Humans , Male , Obesity/etiology , Overweight , Prevalence , Risk Factors , Spain/epidemiology
6.
J Agric Food Chem ; 49(12): 6006-11, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11743800

ABSTRACT

The proteolysis of bovine serum albumin (BSA) modified by reaction with the lipid peroxidation product 4,5(E)-epoxy-2(E)-heptenal was studied to better understand the loss of digestibility observed in oxidized lipid-damaged proteins. BSA was incubated for different periods of time with eight concentrations of the epoxyalkenal and, then, treated for 24 h with chymotrypsin, pancreatin, Pronase, or trypsin. The treatment of BSA with the aldehyde always decreased its proteolysis in relation to that of native BSA, and this inhibition of the proteolysis was related to the concentration of the epoxyalkenal and the reaction time. In fact, this inhibition was correlated with the damage suffered by the protein as a consequence of its reaction with the aldehyde: mainly the development of browning, the denaturation of the protein, and the formation of the oxidized lipid/amino acid reaction product epsilon-N-pyrrolylnorleucine (p < or = 0.0011, 0.0045, and 0.0031, respectively). In addition, epsilon-N-pyrrolylnorleucine added at 0.1 or 1 mM inhibited the proteases assayed and suggested that the inhibition of the proteolysis observed in oxidized lipid-damaged proteins may be related to the formation and accumulation of pyrrolized amino acid residues.


Subject(s)
Lipid Peroxidation , Norleucine/analogs & derivatives , Serum Albumin, Bovine/chemistry , Aldehydes , Chymotrypsin/metabolism , Epoxy Compounds , Hydrolysis , Kinetics , Time Factors
7.
J Agric Food Chem ; 49(9): 4267-70, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11559121

ABSTRACT

Proteins of olive fruit mesocarp are not very well-known at present. However, they have been shown to pass, at least partially, to the olive oil during its elaboration and therefore might be contributing to some of the special characteristics of this vegetable oil. In this study, protein content and composition were determined in olive fruits, cv. Arbequina and Picual, at three stages of ripening: green, spotted, and purple. Mesocarp proteins constituted 1.3-1.8% of the dry weight of the olive fruit, and cultivar and fruit ripening did not produce important changes in mesocarp protein content or composition. In addition, this composition was also similar to the amino acid composition of a 4.6-kDa polypeptide, which is the major protein component of olive oils and of oil bodies of olive fruit mesocarp, suggesting that this polypeptide is likely to be a major component of mesocarp proteins. There was, also, a relationship between the oil content of the olive fruit and the protein content determined, suggesting a stabilizing function of these proteins in the oil bodies of the olive fruit, analogously to the role suggested for oleosins. This stabilizing function does not seem to be extended to olive oils because when the polypeptides isolated were added at 20 ppm to soybean oil, the stability of the oil increased only slightly, suggesting that if these compounds play some role in the stability of the oils, this should be mostly a consequence of the possible interactions among these protein components and other olive oil antioxidant constituents.


Subject(s)
Amino Acids/analysis , Fruit/chemistry , Plant Proteins/analysis , Antioxidants/metabolism , Olive Oil , Oxidation-Reduction , Plant Oils , Time Factors
8.
Chem Res Toxicol ; 14(5): 582-8, 2001 May.
Article in English | MEDLINE | ID: mdl-11368558

ABSTRACT

The consequences of oxidative stress on microsomal proteins were analyzed by studying their pyrrolization and the antioxidative activity of the modified proteins produced. The microsomal system consisted of freshly prepared trout muscle microsomes, which were oxidized in the presence of 5 microM Cu(2+), 1 mM Fe(3+)/5 mM ascorbate, or 1 mM Cu(2+)/10 mM H(2)O(2). Pyrroles on proteins were detected by forming Ehrlich adducts with p-(dimethylamino)benzaldehyde and by determination of epsilon-N-pyrrolylnorleucine (Pnl) by capillary electrophoresis. Their antioxidative activity was studied by testing two model pyrrolized proteins (dimeric and monomeric modified bovine serum albumin: DBSA and MBSA, respectively), which were produced in the reaction of BSA and 4,5(E)-epoxy-2(E)-heptenal. These proteins were assayed at a concentration of 10-40 microg/mL, which was selected because at this concentration both DBSA and MBSA had a concentration of Pnl similar to the Pnl concentration produced in oxidized microsomes. Both DBSA and MBSA significantly (p < 0.05) protected against lipid peroxidation, assessed by the formation of thiobarbituric acid reactive substances (TBARS), and protein damage, evaluated by amino acid analysis, for the three systems assayed, and this protection was always higher than that exhibited by BSA, which was used as control. The order of effectiveness was DBSA > MBSA > BSA and was parallel to the Pnl content in the assayed proteins. These results suggest that antioxidative activity of BSA may also be related to its ability to react with lipid oxidation products and to produce modified BSA with antioxidative activity. This mechanism may also be contributing to the antioxidative activity exhibited by many proteins.


Subject(s)
Antioxidants/pharmacology , Proteins/metabolism , Pyrroles/metabolism , Reactive Oxygen Species/metabolism , Animals , Antioxidants/metabolism , Electrophoresis, Capillary/methods , Lipid Peroxidation/drug effects , Microsomes/chemistry , Microsomes/metabolism , Muscles/cytology , Norleucine/analogs & derivatives , Norleucine/analysis , Norleucine/chemistry , Oxidative Stress/physiology , Proteins/chemistry , Proteins/pharmacology , Pyrroles/chemistry , Pyrroles/pharmacology , Serum Albumin, Bovine/chemistry , Serum Albumin, Bovine/metabolism , Thiobarbituric Acid Reactive Substances/analysis , Trout
9.
Anal Chem ; 73(3): 698-702, 2001 Feb 01.
Article in English | MEDLINE | ID: mdl-11217787

ABSTRACT

A method for the determination of proteins in fats and oils is described. Proteins were sequentially precipitated with acetone and hydrolyzed, and the produced amino acids were fractionated and quantificated. This analysis protocol afforded a method of high sensitivity and specificity which was fully evaluated and validated. The data obtained showed good accuracy and linearity with excellent reproducibility and recovery. When the method was applied to 40 olive oils, all of them contained proteins in the range 10-50 microg/100 g of oil, suggesting that proteins are nonpreviously described minor components of these oils. In addition, the proteins precipitated were almost exclusively composed by one polypeptide of apparent 4600 molecular weight, which was isolated from olive drupes and partially characterized by amino acid analysis. Similar polypeptides were also detected in other seeds, suggesting that they may constitute a new class of polypeptides in plants with oleosin-like characteristics. Furthermore, the method was also applied to different fats and oils, and all the samples analyzed contained proteins, suggesting that natural fats and oils always contain polypeptides and/or proteins as minor components. These results also suggest that some peptides are soluble in lipid matrixes, where they might be playing unknown functions. The developed procedure provides a methodology for the determination of these components.


Subject(s)
Dietary Fats, Unsaturated/analysis , Dietary Fats/analysis , Peptides/analysis , Proteins/analysis , Chromatography, High Pressure Liquid , Electrophoresis, Polyacrylamide Gel , Reproducibility of Results , Sensitivity and Specificity , Spectrophotometry, Ultraviolet
10.
J Agric Food Chem ; 48(8): 3152-8, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10956084

ABSTRACT

Recent studies have hypothesized that pyrrole formation and polymerization may be contribute to the nonenzymatic browning produced in both oxidized lipid/protein reactions and the Maillard reaction. To develop a methodology that would allow investigation of the contribution of this browning mechanism, the kinetics of formation of color, fluorescence, and pyrrolization in 4, 5(E)-epoxy-2(E)-heptenal/lysine and linolenic acid/lysine model systems were studied. In both cases similar kinetics for the three measurements were observed at the two temperatures assayed (37 and 60 degrees C), and there was a high correlation among color, fluorescence, and pyrrolization measurements obtained as a function of incubation time. Because the color and fluorescence production in the 4,5(E)-epoxy-2(E)-heptenal/lysine system is a consequence of pyrrole formation and polymerization, the high correlations observed with the unsaturated fatty acid also suggest a contribution of the pyrrole formation and polymerization to the development of color and fluorescence observed in the fatty acid/lysine system. Although the contribution of other mechanisms cannot be discarded, all of these results suggest that when the pyrrole formation and polymerization mechanism contributes to the nonenzymatic browning of foods, a high correlation among color, fluorescence, and pyrrolization measurements should be expected.


Subject(s)
Maillard Reaction , Pyrroles/chemical synthesis , Amines/chemistry , Lysine/chemistry , Magnetic Resonance Spectroscopy , Mass Spectrometry , Polymers , Pyrroles/chemistry , alpha-Linolenic Acid/chemistry
11.
Chem Res Toxicol ; 13(6): 501-8, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10858323

ABSTRACT

Bovine serum albumin (BSA) was incubated for different periods of time and in the presence of several concentrations of 4, 5(E)-epoxy-2(E)-heptenal, at pH 7.4 and 37 degrees C, in an effort to analyze the changes produced in its structure as a consequence of its reaction with this product of lipid oxidation. The epoxyalkenal modified the primary structure of BSA as determined by lysine losses and formation of oxidative stress product epsilon-N-pyrrolylnorleucine (Pnl), which depended on the concentration of the aldehyde and the incubation time. These changes also modified secondary and tertiary structures of the protein, which were determined by studying protein denaturation and polymerization. In addition, all these modifications were parallel to the development of color and fluorescence, which were produced as a consequence of the formation and polymerization of pyrrole amino acid residues. The above results indicated that epoxyalkenals modify the protein structure and develop color and fluorescence. A failure in the degradation of these modified proteins might induce their accumulation and, thus, participation in lipofuscin or age pigments formation.


Subject(s)
Aldehydes/pharmacology , Epoxy Compounds/pharmacology , Protein Conformation/drug effects , Serum Albumin, Bovine/drug effects , Animals , Cattle , Serum Albumin, Bovine/chemistry
12.
J Agric Food Chem ; 47(5): 1942-7, 1999 May.
Article in English | MEDLINE | ID: mdl-10552475

ABSTRACT

epsilon-N-Pyrrolylnorleucine was determined in different fresh food products to study its presence as a normal component of food proteins. Twenty-two different products were screened: cod, cuttlefish, salmon, sardine, trout, beef, chicken, pork, broad bean, broccoli, chickpea, garlic, green pea, lentil, mushroom, soybean, spinach, sunflower, almond, hazelnut, peanut, and walnut. Foods were homogenized, their proteins were precipitated with trichloroacetic acid and hydrolyzed with 2 N NaOH for 20 h, and the epsilon-N-pyrrolylnorleucine content was determined by capillary electrophoresis. The epsilon-N-pyrrolylnorleucine, which was identified by HPLC/MS in sardine muscle hydrolysate, ranged in the 22 foods analyzed from 0.24 to 6.36 micromol/g. This concentration was correlated with the protein content of the food (r = 0.687, p = 0.00041). In addition, the epsilon-N-pyrrolylnorleucine/lysine ratio was found to be a function of the lipid, iron, and protein contents of the food (r = 0.881, p < 0.0001) and was directly correlated with lipid and iron contents and inversely correlated with the protein content. These results are in agreement with the oxidative stress origin proposed for epsilon-N-pyrrolylnorleucine and suggest that the epsilon-N-pyrrolylnorleucine/lysine ratio is a characteristic of each food. In addition, epsilon-N-pyrrolylnorleucine seemed to be a normal component of many fresh food products, in which it may be acting as a natural antioxidant.


Subject(s)
Food Analysis , Meat/analysis , Norleucine/analogs & derivatives , Nuts/chemistry , Vegetables/chemistry , Animals , Cattle , Chickens , Fishes , Norleucine/analysis , Swine
13.
J Agric Food Chem ; 47(2): 742-7, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10563963

ABSTRACT

Bovine serum albumin (BSA) was incubated for 24 h in the presence of 10 mM ribose (RI), methyl linoleate hydroperoxides, or the secondary products of methyl linoleate oxidation (SP), at five temperatures (25, 37, 50, 80, and 120 degrees C) and different pHs (4, 7, and 10), to study the influence of these variables in the browning, fluorescence, amino acid losses, and pyrrolization of the modified proteins. All treated proteins exhibited similar colors and fluorescence spectra, and the spectra of their Ehrlich adducts were also analogous. However, at 25-50 degrees C the proteins treated with oxidized lipids exhibited higher color changes, amino acid losses, and pyrrolization than the BSA treated with RI, and these effects were much higher in proteins treated with RI at 80-120 degrees C. The effect of pH was similar in proteins treated with RI or SP. These results suggested a similarity for browned proteins obtained from both carbohydrates and oxidized lipids. In addition, both reactions seem to be complementary, because melanoidin formation derived from oxidized lipids can be produced under conditions different from those carbohydrate/protein reactions.


Subject(s)
Carbohydrates/chemistry , Lipids/chemistry , Proteins/chemistry , Color , Hydrogen-Ion Concentration , Oxidation-Reduction , Serum Albumin, Bovine/chemistry , Temperature
14.
J Agric Food Chem ; 47(2): 748-52, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10563964

ABSTRACT

The antioxidative activity of nonenzymatically browned bovine serum albumin (BSA) produced by reaction with ribose (RI), hydroperoxides of methyl linoleate oxidation (HP), and secondary products of methyl linoleate oxidation (SP), at different pHs (4, 7, and 10) and temperatures (25, 37, 50, 80, and 120 degrees C), was studied to compare the antioxidative effects of carbohydrate- and oxidized lipids-modified proteins. The modified proteins (RIBSA, HPBSA, and SPBSA) were tested for antioxidative activity (at 100 ppm) in soybean oil using the thiobarbituric acid-reactive substances (TBARS) assay. All of them decreased significantly (p < 0.05) the TBARS formation in the oil and exhibited different effectiveness as a function of the temperature and the pH of the medium. In addition, there was a good correlation between the antioxidative activity of the protein and the amino acid losses produced during the nonenzymatic browning. These results are in agreement with an analogous and complimentary contribution of both Maillard and oxidized lipid/protein reactions to the antioxidative activity produced in foods during processing and storage.


Subject(s)
Carbohydrates/chemistry , Lipids/chemistry , Proteins/chemistry , Antioxidants/chemistry , Color , Hydrogen-Ion Concentration , Oxidation-Reduction , Serum Albumin, Bovine/chemistry , Temperature
15.
Chem Res Toxicol ; 12(7): 654-60, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10409406

ABSTRACT

The reactions of 4,5(E)-epoxy-2(E)-heptenal with 4-methylimidazole and N(alpha)-acetyl-L-histidine methyl ester were studied to characterize the adducts produced in the modification of histidine residues by epoxyalkenals and to develop a methodology for the determination of these adducts in protein hydrolysates. The reaction products, which were isolated and characterized, resulted in the Michael adducts produced in the addition of one of the imidazolic nitrogens to the carbon-carbon double bond of the epoxyalkenal. Only some of the theoretical isomers were produced. Thus, in the reaction with 4-methylimidazole, the main product was 4, 5-epoxy-3-(4-methylimidazol-1-yl)heptanol (88%), although the formation of 4,5-epoxy-3-(5-methylimidazol-1-yl)heptanol (12%) was also observed. On the other hand, the reaction with N(alpha)-acetyl-L-histidine methyl ester produced exclusively N(alpha)-acetyl-1-[1'-(1' ',2' '-epoxybutyl)-3'-hydroxypropyl]-L-histidine methyl ester. This last compound was used to develop a procedure for the determination of 4, 5(E)-epoxy-2(E)-heptenal-histidine adducts in protein hydrolysates. When this procedure was applied to the analysis of bovine serum albumin treated with 0.01-10 mM 4,5(E)-epoxy-2(E)-heptenal, the formation of the adduct was observed and its concentration increased with the concentration of the aldehyde and the incubation time, and was parallel to the histidine losses observed in the protein after acid hydrolysis as well as to the formation of protein carbonyls. In addition, the number of histidine residues lost in the protein was very similar to the number of adduct residues produced, suggesting that the addition reaction is the major mechanism for histidine losses suffered by proteins following their reaction with epoxyalkenals.


Subject(s)
Aldehydes/chemistry , Epoxy Compounds/chemistry , Histidine/chemistry , Chromatography, High Pressure Liquid , Histidine/analogs & derivatives , Hydrolysis , Imidazoles/chemistry , Serum Albumin, Bovine/chemistry
16.
Anal Biochem ; 262(2): 129-36, 1998 Sep 10.
Article in English | MEDLINE | ID: mdl-9750127

ABSTRACT

The Ehrlich reaction was optimized to determine pyrrolized proteins produced as a consequence of lipid peroxidation and oxidative stress. The procedure consisted of the treatment of the modified protein with p-(dimethylamino)benzaldehyde at a controlled acidity and temperature, and the determination of adducts produced against the blank obtained in the absence of the reagent. The extinction coefficient of Ehrlich adducts was calculated by using epsilon-N-pyrrolylnorleucine (Pnl) as standard and was 35,000 M-1 cm-1. The response was linear and reproducible within the range 0. 16-20 microM Pnl. The assay was applied to determination of pyrrole content in bovine serum albumin, bovine alpha-globulins, bovine gamma-globulins, and mixtures of them, incubated overnight with 1 mM of 4,5(E)-epoxy-2(E)-heptenal, obtaining results similar to those from determination of Pnl by capillary electrophoresis after basic hydrolysis of the protein. The method was also applied to pyrrole determination in bovine plasma proteins either incubated with epoxyalkenals, hydroxyalkenals, lipid hydroperoxides, and secondary products of lipid peroxidation, or oxidized with Fe3+/ascorbate. All these treatments produced pyrrolization of plasma proteins and all Ehrlich adducts gave very similar absorbance spectra with the exception of that produced in the treatment with hydroxyalkenals. The above results suggest that protein pyrrolization is a normal consequence of the lipid peroxidation process and of oxidative stress, and that Ehrlich adducts may be valid to determine this pyrrolization.


Subject(s)
Lipid Peroxides/pharmacology , Proteins/analysis , Spectrophotometry/methods , Aldehydes/metabolism , Amino Acids/analysis , Animals , Ascorbic Acid/metabolism , Benzaldehydes/metabolism , Blood Proteins/analysis , Cattle , Epoxy Compounds/metabolism , Ferric Compounds/metabolism , Globulins/analysis , Kinetics , Lipid Peroxidation/physiology , Molecular Structure , Oxidation-Reduction , Oxidative Stress/physiology , Pyrroles/analysis , Serum Albumin/analysis
17.
Biochemistry ; 36(50): 15765-71, 1997 Dec 16.
Article in English | MEDLINE | ID: mdl-9398306

ABSTRACT

Three oxidized lipid/amino acid reaction products (OLAARPs): 1-methyl-4-pentyl-1,4-dihydropyridine-3,5-dicarbaldehyde, 1-(5-amino-1-carboxypentyl)pyrrole, and N-(carbobenzyloxy)-1(3)-[1-(formylmethyl)hexyl]-l-histidine dihydrate, were prepared and tested for antioxidative activity in a microsomal system in order to investigate the effect that OLAARP formation may be playing in the oxidative stress process. The microsomal system consisted of freshly prepared trout muscle microsomes, which were oxidized in the presence of 5 microM Cu2+, 1 mM Fe3+/5 mM ascorbate, or 1 mM Cu2+/10 mM H2O2, and the compound to be tested as antioxidant added at 50 microM. At different periods of time, samples were tested for lipid peroxidation, assessed by the formation of thiobarbituric acid reactive substances (TBARS), and protein damage, which was evaluated by the formation of protein carbonyls and amino acid analysis. The three OLAARPs and butylated hydroxytoluene significantly (p < 0.05) protected against lipid peroxidation and protein damage for the three systems assayed. On the contrary, neither the amino acids used in the preparation of OLAARPs nor alpha-tocopherol, mannitol, aminoguanidine, or 4, 5-dihydroxy-1,3-benzenedisulfonic acid exhibited this constant protection. Because OLAARPs were produced at inhibitory levels during microsomal lipid peroxidation, these results suggest that OLAARP formation may be an antioxidative defense mechanism by which oxidative stress is feed-back-inhibited, delaying the damage caused by reactive oxygen species.


Subject(s)
Antioxidants/pharmacology , Oxidative Stress/drug effects , Alanine/analogs & derivatives , Alanine/chemical synthesis , Alanine/pharmacology , Aldehydes/chemical synthesis , Aldehydes/pharmacology , Amino Acids/chemical synthesis , Amino Acids/pharmacology , Animals , Ascorbic Acid/pharmacology , Butylated Hydroxytoluene/pharmacology , Copper/pharmacology , Dihydropyridines/chemical synthesis , Dihydropyridines/pharmacology , Feedback , Ferric Compounds/pharmacology , Free Radical Scavengers/pharmacology , Hydrogen Peroxide/pharmacology , Microsomes/drug effects , Microsomes/metabolism , Molecular Structure , Muscles/drug effects , Muscles/metabolism , Oncorhynchus mykiss , Oxidative Stress/physiology , Pyrroles/chemical synthesis , Pyrroles/pharmacology , Reactive Oxygen Species/metabolism , Thiobarbituric Acid Reactive Substances/analysis
18.
Nutr Hosp ; 10(6): 358-63, 1995.
Article in Spanish | MEDLINE | ID: mdl-8599621

ABSTRACT

We present the results of a study done in the departments of hospital pharmacy of our country with the aim of knowing their participation in the use and clinical follow up of patients with enteral nutrition. 293 questionnaires were sent out, and 121 were filled out and returned (41.3%). The responses were classified into three groups, according to the number of hospital beds, considering > or = 1000 (large), 500-1000 (medium), and < or = 500 (small). The data were analyzed by means of a statistical program (R-Sigma Horus). 79% (68) of the small hospitals have a unitary dose drug dispensation system, and the Enteral Nutrition was distributed through this system in 53% (50) of them; only 29% (27) of them have a stock of these preparations on the wards. 93% (14) and 65% (54) of the large and small hospitals respectively, prefer the use of enteral nutrition as opposed to parenteral nutrition. 85% (11) of the large hospitals have protocols for the use of enteral nutrition, this being 62% (10) and 59% (47) in medium and small hospitals. The committees for artificial nutrition are present in 75% of the large hospitals, in addition to which, in 66% of these there is a nutritional support team. A pharmacist from the department of pharmacy participates in both multidisciplinary groups. If it is necessary to manipulate the enteral nutrition preparations, in 30% of the departments of pharmacy of the smaller hospitals, this is centralized, being done by personnel of the department itself; in 59% of them (19) there is a specific area for the elaboration, which is not the case in large hospitals. Drugs are mixed with the enteral nutrition in 25% (1), 12% (1), and 9% (4) of the large, medium and small hospitals respectively. There is great, active participation of the hospital pharmacists in the activities of the multidisciplinary nutritional support systems, although at the present time, the involvement of the departments of pharmacy in the centralization of the manipulation of the enteral nutrition is reduced. It is necessary therefore, to implement the development of enteral nutrition programs with a quality guarantee from the departments of pharmacy.


Subject(s)
Enteral Nutrition , Pharmacy Service, Hospital , Enteral Nutrition/statistics & numerical data , Follow-Up Studies , Humans , Parenteral Nutrition/statistics & numerical data , Patient Care Team/statistics & numerical data , Pharmacy Service, Hospital/statistics & numerical data , Spain , Surveys and Questionnaires
19.
Biochim Biophys Acta ; 1258(3): 319-27, 1995 Oct 05.
Article in English | MEDLINE | ID: mdl-7548203

ABSTRACT

The reactions of 13-hydroperoxy-9(Z),11(E)-octadecadienoic acid (13-LOOH) and its degradation product 4,5(E)-epoxy-2(E)-decenal with butylamine and lysine were studied to determine whether pyrrole derivatives isolated in model reactions were produced in complex systems involving hydroperoxides. Incubated reaction mixtures were studied by gas chromatography coupled with mass spectrometry or high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS), and some compounds were isolated by column chromatography or semipreparative HPLC, and identified by 1H- and 13C-nuclear magnetic resonance spectroscopy and MS. The reaction of epoxyalkenals with amino groups produced two types of pyrrole derivatives: 1-substituted 2-(1'-hydroxyalkyl)pyrroles and 1-substituted pyrroles. 1-Substituted 2-(1'-hydroxyalkyl)pyrroles were responsible for the development of color and fluorescence by a polymerization reaction, which implied the formation of dipyrrylmethanes and dipyrrylmethenes. 1-Substituted pyrroles were final products in these reactions and their determination might be used as an index of oxidative stress. The above reactions were also observed between 13-LOOH and amino compounds, and suggested that the pyrrole polymerization mechanism plays a role in the fluorescence observed by reaction of hydroperoxides and amino groups.


Subject(s)
Aldehydes/metabolism , Butylamines/metabolism , Epoxy Compounds/metabolism , Linoleic Acids/metabolism , Lysine/metabolism , Pyrroles/metabolism , Aldehydes/chemistry , Chromatography, High Pressure Liquid , Electrophoresis, Capillary , Epoxy Compounds/chemistry , Lipid Peroxidation , Lipid Peroxides/metabolism , Lipoxygenase/metabolism , Mass Spectrometry , Molecular Structure , Oxidation-Reduction , Spectrometry, Fluorescence
20.
Lipids ; 30(6): 477-83, 1995 Jun.
Article in English | MEDLINE | ID: mdl-7651073

ABSTRACT

epsilon-N-Pyrrolylnorleucine (Pnl) is a product of the reaction between the lipid peroxidation product 4,5(E)-epoxy-2(E)-heptenal (EH) and the epsilon-amino group of lysine. Because Pnl might also be produced in proteins, a specific method to determine this compound in protein hydrolysates has been developed. Homoarginine, added as the internal standard, and Pnl are derivatized with diethyl ethoxymethylenemalonate and analyzed by micellar electrokinetic capillary chromatography. The method also analyzes lysine and arginine, and these analyses were useful in determining losses of these amino acids after treatment with EH. The lowest concentration of Pnl detected with acceptable reproducibility is 5 nmol/mL, and the coefficient of variation was determined from four standard curves assayed on separate days. Detector response was linear for samples containing 1.6 to 74 nmol/mL of Pnl. The assay was applied in investigations of Pnl production in bovine serum albumin (BSA) and trout muscle microsomes treated with EH. When BSA was incubated overnight with 30 mM EH, 76% of lysine residues were modified, and a part of these residues were detected as Pnl (12%). Pnl formation was also detected when trout muscle microsomes were incubated for three hours with 1 or 10 mM EH. These results show that Pnl is produced in vitro in proteins treated with the lipid peroxidation product EH, and suggest that Pnl might also be constituent of in vivo damaged proteins by their reaction with oxidized lipids.


Subject(s)
Chromatography/methods , Lysine/chemistry , Microsomes/chemistry , Muscles/ultrastructure , Norleucine/analogs & derivatives , Proteins/analysis , Trout , Aldehydes/chemistry , Animals , Capillary Action , Epoxy Compounds/chemistry , Hydrolysis , Kinetics , Lipid Peroxidation , Micelles , Norleucine/analysis , Serum Albumin, Bovine/analysis
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