Arginine-guanidinoacetate-creatine pathway in preterm newborns: creatine biosynthesis in newborns.

The phosphocreatine/creatine system is fundamental for the proper development of the embryonic brain. Being born prematurely might alter the creatine biosynthesis pathway, in turn affecting creatine supply to the developing brain. We enrolled 53 preterm and very preterm infants and 55 full-term newborns.

Expression of proinflammatory factors in renal cortex induced by methylmalonic acid.

Background: Methylmalonic aciduria is an inborn error of metabolism that causes renal failure and tubulointerstitial (TI) nephritis as complications. This study aimed to examine the levels of expression of several genes related to inflammation, oxidative stress, and mitochondrial function in the renal cortex of rats receiving methylmalonic acid (MMA).

Methods: Rats received MMA subcutaneously for a month.

Fatty acid profile in patients with phenylketonuria and its relationship with bone mineral density.

Background: Patients with phenylketonuria (PKU) undergo a restrictive vegan-like diet, with almost total absence of n-3 fatty acids, which have been proposed as potential contributors to bone formation in the healthy population. The PKU diet might lead these patients to bone mass loss and, consequently, to the development of osteopenia/osteoporosis. Therefore, we proposed to analyze their plasma fatty acid profile status and its relationship with bone health.

Methylation cycle, arginine-creatine pathway and asymmetric dimethylarginine in paediatric renal transplant.

Background: Hyperhomocysteinaemia represents an important cause of morbidity in recipients of renal transplants, but few investigations have been carried out to evaluate the status of the methylation cycle and its relation with levels of new cardiovascular biomarkers, such as asymmetric dimethylarginine (ADMA).

Methods: Twenty-six children and adolescents aged 7-18 years (17 male, 9 female) with stable renal transplants were recruited for the study. None had received treatment with folate, vitamin B(12) or statins.

Persistence of essential fatty acid deficiency in cystic fibrosis despite nutritional therapy.

To study the evolution of plasma fatty acid composition of patients with cystic fibrosis (CF) in relation to nutritional status, pancreatic function, and development of CF-related liver disease (CFRLD) and diabetes mellitus, 24 CF pediatric patients with stable pulmonary disease were studied before and after an approximate period of 8 y. Nutritional status, pulmonary function, pancreatic function, and presence of CFRLD or diabetes mellitus were recorded. Results were compared with data obtained in 83 healthy children.

Determination of creatine and guanidinoacetate by GC-MS: study of their stability in urine at different temperatures.

Objectives: Evaluation of a GC-MS method using N-tert-butyldimethylsilyl-N-methyltrifluoroacetamide (MTBSTFA) as the silylating agent for GC-MS. Study of the stability of creatine and guanidinoacetate in urine.

Design And Methods: 22 urines were kept at RT, 4 degrees C and -30 degrees C for 15 days.

Fatty acid deficiency profile in children with food allergy managed with elimination diets.

Aim: To evaluate plasma fatty acid (FA) composition of children with food allergy undergoing elimination diets that avoided the offending antigens.

Methods: Twenty-five children (14 male, 11 female) aged 3.8 +/- 1.

The arginine-creatine pathway is disturbed in children and adolescents with renal transplants.

Cardiovascular disease is an important cause of morbidity in recipients of renal transplants. The aim of the present study was to analyze the status of the arginine-creatine pathway in such patients, given the relationship between the arginine metabolism and both renal function and the methionine-homocysteine cycle. Twenty-nine children and adolescents (median age 13, range 6-18 years), who had received a renal allograft 14.

Stability of urinary glycosaminoglycans in patients with mucopolysaccharidoses.

Objective: The aim of this work is to investigate the degradation of urinary glycosaminoglycans (GAGs) at different storage temperatures, in order to identify whether frozen transportation to reference laboratories is necessary. An improved method for the determination of total GAGs with 1,9-dimethylmethylene blue (DMB) is presented.

Design And Methods: Urine samples of 37 patients suffering from mucopolysaccharidoses (MPS) were analyzed in this study (13 Hunter, 6 Maroteaux-Lamy, 6 Morquio, 6 Sanfilippo, 5 Hurler-Scheie, and 1 Sly).

Essential fatty acid deficiency profile in patients with nephrotic-range proteinuria.

Plasma free fatty acids are bound to albumin, filtered through the glomeruli, and reabsorbed at the proximal nephron. The aim of the present investigation was to determine if urinary loss of fatty acids results in essential fatty acid (EFA) deficiency in patients with nephrotic-range proteinuria. We studied 12 patients aged 9 months to 23 years (eight male, four female) four suffering from congenital nephrotic syndrome (NS) and eight from different renal diseases.

Abnormalities in plasma fatty acid composition in human immunodeficiency virus-infected children treated with protease inhibitors.

Aim: To study plasma fatty acid composition in human immunodeficiency virus-infected children treated with protease inhibitors and its relation with other components of the metabolic syndrome observed after this therapy.

Design: Cross-sectional study from collected clinical database.

Subjects: 17 children with HIV infection treated with protease inhibitors.

Influence of diet on atherogenic risk in children with renal transplants.

Cardiovascular disease is one of the main causes of morbidity and mortality in recipients of renal transplants. Although the risk for cardiovascular disease is in part genetically determined, it may also be influenced by diet. The aim of the present study was to analyze the cross-sectional association of dietary intake of nutrients with biochemical markers of atherogenic risk.

Square wave voltammetric determination of the angiotensin-converting enzyme inhibitors cilazapril, quinapril and ramipril in pharmaceutical formulations.

The angiotensin-converting enzyme inhibitors cilazapril, quinapril and ramipril are reduced at a hanging mercury drop electrode in the pH range 3.5-13 using Britton-Robinson buffers as supporting electrolyte and KCl as ionic medium. Square wave voltammetry has proved to be the most suitable electroanalytical technique for the quantitative voltammetric determination of these antihypertensive drugs.

Determination of the angiotensin-converting enzyme inhibitor quinapril and its metabolite quinaprilat in pharmaceuticals and urine by capillary zone electrophoresis and solid-phase extraction.

Quinapril is an antihypertensive drug commonly used in the treatment of hypertension and congestive heart failure. In this work, a capillary zone electrophoresis system is optimized for the analysis of quinapril and its active metabolite quinaprilat in urine, as well as for the determination of the drug and its combination with hydrochlorothiazide in pharmaceuticals. The separation takes place in a fused-silica capillary.