Conventional wheat milling generates important volumes of wheat bran (WB), which is a concentrated source of polyphenols and insoluble fiber. In terms of health benefits and based on epidemiological and experimental evidence, these compounds contribute to reducing the risk of certain chronic pathologies. Protein concentration is the main quality factor conditioning wheat use in the agroindustry.
View Article and Find Full Text PDFBackground: Preterm infants are generally fed through nasogastric enteral feeding tubes (NEFTs). The aim of this work was to evaluate the role of NEFTs in the initial colonization of the preterm gut and its evolution within the first 2 weeks after birth.
Methods: For this purpose, fecal and NEFT-derived samples from 30 preterm infants hospitalized in a neonatal intensive care unit (NICU) were collected from birth to the second week of life.
The purpose of this study was to assess the nursing workload at admission to and discharge from intensive care of three groups of patients (i.e., acute coronary syndrome, acute respiratory failure, and sepsis).
View Article and Find Full Text PDFObjective: to evaluate the effectiveness and safety of a nurse-led blood glucose control protocol in a medical ICU.
Method: a descriptive, prospective study was carried out for a period of 13 months. All blood glucose values from patients on insulin therapy for intensive glycemic control were recorded daily.
8-Anilino-1-naphthalenesulfonic acid (ANS) is a popular fluorescence probe, broadly used for the analysis of proteins, but the nature of its interaction with proteins and the high increase in the fluorescence intensity that takes place upon such process are still unclear. In the last few years, isothermal titration calorimetry has been used to characterize the nature of the interaction of this dye with proteins. The analysis of the binding isotherms of these studies has not considered the dimerization equilibrium of ANS, which is pH dependent, and it can result in serious errors in the data analysis.
View Article and Find Full Text PDFBackground & Aims: Patients with cirrhosis undergoing selective intestinal decontamination with norfloxacin show a reduction in serum cytokine levels, probably because of a combined effect of norfloxacin on bowel flora and neutrophils.
Methods: Thirty-one patients with cirrhosis receiving norfloxacin (400 mg/day) were included. Blood samples were collected at 0.
Somatic angiotensin I-converting enzyme (s-ACE) plays a central role in blood pressure regulation and has been the target of most antihypertensive drugs. A displacement isothermal titration calorimetry method has been used to accurately determine the binding constant of three strong s-ACE inhibitors. Under the experimental conditions studied in this work, the relative potency of the inhibitors was determined to be enalaprilat>lisinopril>captopril.
View Article and Find Full Text PDFHydantoin racemase enzyme plays a crucial role in the reaction cascade known as "hydantoinase process." In conjunction with a stereoselective hydantoinase and a stereospecific carbamoylase, it allows the total conversion from D,L-5-monosubstituted hydantoins, with a low rate of racemization, to optically pure D- or L-amino acids. Residues Cys76 and Cys181 belonging to hydantoin racemase from Sinorhizobium meliloti (SmeHyuA) have been proved to be involved in catalysis.
View Article and Find Full Text PDFAllosteric enzymes have very complex kinetic behaviours which are primarily interpreted through simplified models. To describe the functional properties of liver and muscle glycogen phosphorylase isozymes we have developed an experimental strategy based on the measurements of initial reaction rates in the presence of different concentrations of the effectors glucose-1-phosphate and methyl-xanthines. Using the extensive structural information available for the two glycogen phosphorylase conformers T (inactive) and R (active) with different ligands, we have applied the Monod-Wyman-Changeux model and analysed the results in the context of the exclusive binding of the inhibitors to the T state, meanwhile the substrate glucose-1-phosphate binds to both, the R and T states.
View Article and Find Full Text PDFPurified site-directed mutants of Sinorhizobium meliloti CECT 4114 l-N-carbamoylase (SmLcar) in which Glu132, His230, Asn279 and Arg292 were replaced have been studied by kinetic methods and isothermal titration calorimetry (ITC). The importance of His230, Asn279 and Arg292 residues in the recognition of N-carbamoyl-l-alpha-amino acids has been proved. The role of Glu132 has been confirmed in substrate hydrolysis.
View Article and Find Full Text PDFJ Biochem Biophys Methods
April 2006
Isothermal titration calorimetry (ITC) has been applied to the determination of the activity of D-hydantoinase (EC 3.5.2.
View Article and Find Full Text PDFHydantoin racemase enzyme together with a stereoselective hydantoinase and a stereospecific d-carbamoylase guarantee the total conversion from d,l-5-monosubstituted hydantoins with a low velocity of racemization, to optically pure d-amino acids. Hydantoin racemase from Sinorhizobium meliloti was expressed in Escherichia coli. Calorimetric and fluorescence experiments were then carried out to obtain the thermodynamic binding parameters, deltaG, deltaH and DeltaS for the inhibitors L- and D-5-methylthioethyl-hydantoin.
View Article and Find Full Text PDFBackground And Objective: Recent studies support the use of non invasive ventilation (NIV) in patients with acute cardiogenic pulmonary edema (ACPE). We aimed to evaluate the factors related to the success of the technique in patients admitted to an intensive care unit (ICU) with ACPE.
Patients And Method: An observational prospective study was performed in ICU.
Biochemistry
February 2005
Glutathione S-transferases are a family of multifunctional enzymes involved in the metabolism of drugs and xenobiotics. Two tyrosine residues, Tyr 7 and Tyr 111, in the active site of the enzyme play an important role in the binding and catalysis of substrate ligands. The crystal structures of Schistosoma japonicum glutathione S-transferase tyrosine 7 to phenylalanine mutant [SjGST(Y7F)] in complex with the substrate glutathione (GSH) and the competitive inhibitor S-octylglutathione (S-octyl-GSH) have been obtained.
View Article and Find Full Text PDFDissociation and unfolding of homodimeric glutathione S-transferase Y7F mutant from Schistosoma japonicum (SjGST-Y7F) were investigated at equilibrium using urea as denaturant. The conserved residue Tyr7 plays a central role in the catalytic mechanism and the mutation Tyr-Phe yields an inactive enzyme that is able to bind the substrate GSH with a higher binding constant than the wild type enzyme. Mutant SjGST-Y7F is a dimer at pH 6 or higher and a stable monomer at pH 5 that binds GSH (K value of 1.
View Article and Find Full Text PDFInt J Biol Macromol
September 2003
The binding of glutathione (GSH) to the tyrosine 7 to phenylalanine mutant of Schistosoma japonicum glutathione S-transferase (SjGST-Y7F) has been studied by isothermal titration calorimetry (ITC). At pH 6.5 and 25 degrees C this mutant shows a higher affinity for glutathione than wild type enzyme despite an almost complete loss of activity in the presence of 1-chloro-2,4-dinitrobenzene (CDNB) as second substrate.
View Article and Find Full Text PDFJ Chromatogr B Analyt Technol Biomed Life Sci
January 2003
Angiotensin I converting enzyme (ACE) plays a major role in blood pressure regulation, catalyzing the conversion of angiotensin I to the vasoconstrictor angiotensin II. In this report we describe a two-step affinity chromatography method for preparative purification of ACE from pig lung using Concanavalin-A Sepharose 4B and affinity chromatography on Lisinopril Sepharose 6B. The same purification scheme was used to obtain Cobalt-ACE, where zinc ion located at the active site is replaced by cobalt.
View Article and Find Full Text PDFBackground: beta-Blockers and ACE inhibitors reduce early mortality when either one is started in the first hours after myocardial infarction (MI). Considering the close correlation between morphological changes and prognosis, we aimed to investigate whether the benefit of both beta-blockers and ACE inhibitors might reside in a similar protective effect on infarct size or ventricular volume.
Methods And Results: In a randomized, double-blind comparison between early treatment with captopril or atenolol in 121 patients with acute anterior MI, both drugs showed a similar reduction in mean blood pressure.
Background: Acute respiratory tract infections (ARTIs) are among the main causes of morbidity and mortality in children. The bacterial extract OM-85 BV has shown some protective effect for ARTIs in preschool children and a reduction in exacerbations of chronic bronchitis in adults.
Objectives: This trial reports results of a double-masked, placebo-controlled, parallel-group clinical study that assessed the efficacy and tolerability of OM-85 BV in the prevention of ARTIs in school girls living in an orphanage.
Introduction: Intracranial hemorrhage in acute myocardial infarction, under thrombolytic therapeutic, ranges from 0.3 to 3% in different trials. We carried out a study to stabilised the incidence of this complication in ours patients, as well as to analyze its characteristics and asses the presence the predictive factors.
View Article and Find Full Text PDFBackground: The pneumonias associated to mechanical ventilation present great difficulty in diagnosis and have a high mortality. The invasive diagnostic technique of choice in these patients is bronchial curettage by a double telescopic catheter with distal occlusion (OTC) based on its good sensitivity/specificity relation. Recently, the use of a variant of the classical bronchoalveolar lavage (BRL), bronchoalveolar lavage or protected alveolar lavage (PAL) has appeared in the diagnosis of conventional bacterial pneumonia.
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