Steven Yannicelli - Academia.edu (original) (raw)

Papers by Steven Yannicelli

TOPICS IN CLINICAL NUTRITION, 1987

Topics in clinical nutrition

Journal of pediatric …, 2001

Background: Investigators in Italy and Spain have suggested that therapy for patients with phenyl... more Background: Investigators in Italy and Spain have suggested that therapy for patients with phenylketonuria (PKU) may result in essential fatty acid (EFA) deficiency. Objectives of this study were to determine if the diets of patients with PKU in the United States provided ...

Archives of Pediatrics & Adolescent Medicine, 1992

Page 1. due to misinformation and lack of support. I believe that a mother who has the resources ... more Page 1. due to misinformation and lack of support. I believe that a mother who has the resources and abilityto providebreast milk to her infant while she is work¬ ing full-time is indeed breast feeding her infant, and in these times qualifies for sainthood. ...

Journal of Inherited Metabolic Disease, Feb 1, 1992

A child with biotin-non-responsive propionic acidaemia treated with a propiogenic amino acid-rest... more A child with biotin-non-responsive propionic acidaemia treated with a propiogenic amino acid-restricted diet presented with an elevated blood mean corpuscular volume (MCV) of 93.1 r, indicative of macrocytosis, and unusual hair texture with hypopigmentation. Plasma selenium concentration at this time was subnormal (45.9/~g/L), and calculated dietary selenium intake was 4.7 #g/day. After 4 months of selenium supplementation (50 pg/day) plasma selenium concentration normalized (97.7/~g/L) in conjunction with a reduced MCV (84.0fl) and a dramatic improvement in hair growth, colour and length. Two additional periods off and on selenium supplementation, of varying time intervals, resulted in similar clinical changes. We conclude that these clinical changes were due to a deficient intake of dietary selenium.

The objective of this study was to evaluate the effects of a new medical food (Phenex-l) on growt... more The objective of this study was to evaluate the effects of a new medical food (Phenex-l) on growth, nutrient intake and plasma phenylalanine (PHE) and tyrosine (TYR) concentrations of infants and toddlers with phenylketonuria (PKU). Ten full-term infants (5F, 5M) with classical PKU were placed on Phenex-l as their primary protein source at a mean age of 11.8 days (range 7-20 days). Two infants received human milk and eight received proprietary infant formula as the source of PHE. Anthropometric measures were obtained by standard techniques, nutrient intakes were calculated using Amino Acid Analyzer 0 software, and plasma amino acids were analyzed by ion exchange chromatography. When compared to NCHS growth curves, mean head circumference and weight of subjects at birth were at the 75th percentile and greater than the 75th percentile at six months of age. Mean length was at the 75th percentile at birth and at six months of age. During the first three months of study mean PHE intake was 47 mg/kg (range 34-67 mg/kg) and mean TYR intake was 154 mg/kg (range 1 19-291 mg/kg). During the second three months of study mean PHE intake was 36 mg/kg (range 27-61 mg/kg) and mean TYR intake was 214 mg/kg (range 181-257 mg/kg). Mean protein intake during the study was consistently above RDAs; mean energy intake, except at month one, was below RDAs and the lowest mean value was 87% of RDA at 3 months of age. Mean plasma PHE (35 samples) during the course of the study was 258 pmol/L (range 6-1054 pmol/L) (NL 19-76 pmol/L). Twenty-three percent of samples were in the normal range; forty percent were < 121 jpmol/L, 66% were < 303 pmol/L and 89% of samples were < 619 Amol/L. Mean plasma TYR was 47 gmol/L (range 16-98 pmol/L) (NL 25-148 gmol/L). Ninety-one percent of the 35 plasma TYR concentrations were in the normal range. Despite energy intakes that were below RDAs and plasma PHE that was < 121 Amoll/L in 40% of the samples, Phenex-I supported excellent growth and normal plasma TYR concentrations.

Journal of inherited metabolic disease, 2002

Children with phenylketonuric (PKU) are at risk for fractures. This study used a PKU murine model... more Children with phenylketonuric (PKU) are at risk for fractures. This study used a PKU murine model (PAH(enu-2)) to evaluate effects of moderate dietary protein restriction and elevated plasma phenylalanine concentration impact upon bone status. Fifty-four male weanling PKU and control mice were assigned to either an elemental phenylalanine (Phe)-restricted diet (treated) or Phe-unrestricted diet (untreated) with low or normal protein levels for 56 days. Untreated mice and control mice received equal amounts of dietary Phe; treated mice consumed prescribed dietary Phe to maintain plasma Phe concentrations between 120 and 480micromol/L. Plasma Phe, osteocalcin, and urine deoxypyridinoline (DPD)/creatinine were analysed at baseline and at days 28 and 56. Femur strength, bone mineral density (BMD) and bone mineral content (BMC) were analysed at day 56. Moderate protein restriction did not significantly affect bone status. Mean plasma Phe concentrations were significantly greater in untre...

Journal of Inherited Metabolic Disease, 1995

Journal of Inherited Metabolic Disease, 1989

A child with propionic acidaemia, after a stormy infantile course complicated by microcephaly, ha... more A child with propionic acidaemia, after a stormy infantile course complicated by microcephaly, has shown normal subsequent growth and development without dietary protein restriction.

Journal of Inherited Metabolic Disease, 1992

Journal of Inherited Metabolic Disease, 2006

Failure to thrive has been described in patients with organic acidaemias due to a variety of caus... more Failure to thrive has been described in patients with organic acidaemias due to a variety of causes, both organic and inorganic. Failure to thrive in patients with methylmalonic acidaemia (MMA) and propionic acidaemia (PA) may be related to inadequate protein and energy intake rather than pathology of disease. Inadequate protein intake can also result in decreased resting energy expenditure, clinical signs and symptoms of amino acid deficiency, increased risk of infection, and developmental delay. Amino acid-based formulas (also referred to as &amp;amp;amp;amp;amp;#39;medical foods&amp;amp;amp;amp;amp;#39;) provide a key source of nitrogen, energy, vitamins and minerals which, when prescribed appropriately, can promote anabolism and growth. Although protein requirements in patients with organic acidaemias have not been elucidated, providing an adequate balance of protein, energy and other nutrients will help promote growth.

Nutrition Management of Inherited Metabolic Diseases, 2015

Journal of the American Dietetic Association, 1994

Molecular genetics and metabolism, Jan 20, 2016

In December 2014, a workshop entitled "Nutritional Interventions in Primary Mitochondrial Di... more In December 2014, a workshop entitled "Nutritional Interventions in Primary Mitochondrial Disorders: Developing an Evidence Base" was convened at the NIH with the goals of exploring the use of nutritional interventions in primary mitochondrial disorders (PMD) and identifying knowledge gaps regarding their safety and efficacy; identifying research opportunities; and forging collaborations among researchers, clinicians, patient advocacy groups, and federal partners. Sponsors included the NIH, the Wellcome Trust, and the United Mitochondrial Diseases Foundation. Dietary supplements have historically been used in the management of PMD due to their potential benefits and perceived low risk, even though little evidence exists regarding their effectiveness. PMD are rare and clinically, phenotypically, and genetically heterogeneous. Thus patient recruitment for randomized controlled trials (RCTs) has proven to be challenging. Only a few RCTs examining dietary supplements, singly o...

Biological Trace Element Research, Sep 1, 1993

Plasma molybdenum concentrations were determined in children, ages two to 12 yr, with and without... more Plasma molybdenum concentrations were determined in children, ages two to 12 yr, with and without phenylketonuria (PKU). Mean plasma molybdenum concentrations did not differ significantly between the children with PKU (1.33 + 0.5 p~g/L) and without PKU (1.75 + 0.8 ~g/L). Plasma molybdenum concentrations in both groups of children ranged from <1 to 3 ~g/L.

Journal of Inherited Metabolic Disease, Feb 1, 1989

Treatment for phenylketonuria (PKU) involves using low phenylalanine or phenylalanine-free formul... more Treatment for phenylketonuria (PKU) involves using low phenylalanine or phenylalanine-free formulas and supplementation with sufficient phenylalanine for normal growth and development. Eighteen infants with phenylketonuria who received breast milk as their primary phenylalanine source were compared with ten other infants with PKU who received their phenyla[anine primarily from infant formulas. There were no significant differences between breast-fed and formula-fed infants for serum phenylalanine, serum tyrosine, length, weight, head circumference, haematocrit, haemoglobin, serum iron, total iron binding capacity, percentage iron saturation, ferritin, plasma zinc and total calorie intake. Breast-fed infants did show lower mean corpuscular volume at 3 months and 6 months of age. Breast-fed infants had lower phenylalanine intake at 2, 4, 5 and 6 months of age. Breastfed infants at 1, 2, 3, 4, 5 and 6 months of age had lower protein intake. Breast feeding may be continued in the newly diagnosed phenylketonuric infant without any apparent adverse nutritional consequences.

Mol Genet Metab, 2004

Individuals with phenylketonuria (PKU) have been reported to have altered trace mineral status. I... more Individuals with phenylketonuria (PKU) have been reported to have altered trace mineral status. In this study, we evaluated in a murine PKU model whether protein level and level of phenylalanine (PHE) restriction could modulate iron, copper, and zinc status. Fifty-four male weanling PKU and control mice were assigned to receive for 56 days an elemental low or normal protein diet; PKU mice also were assigned to receive PHE restriction (treated) or no restriction (untreated). PHE-restricted mice consumed a prescribed dietary PHE to maintain plasma PHE concentrations between 120 and 480 μmol/L. PHE-unrestricted and control mice received equal amounts of dietary PHE. Intestinal and hepatic copper, iron, and zinc were measured at day 56 and fecal minerals measured at baseline and day 56. Mean plasma PHE concentrations were significantly greater in PKU PHE-unrestricted versus PKU PHE-restricted mice and control mice. Mean intestinal weights when normalized for body weight were significantly greater in PKU mice versus control mice. PKU PHE-unrestricted mice had significantly lower hepatic copper and zinc than PKU PHE-restricted mice, and significantly greater hepatic iron than control and PKU PHE-restricted mice. PKU PHE-unrestricted mice on a low protein diet had hepatic iron concentrations about 1.5 times that of the other mice. Fecal iron concentrations in all mice were significantly greater at day 56 than at baseline. No animal group effects or protein level effects were found for fecal copper, iron, or zinc contents. We conclude that hyperphenylalaninemia alters the metabolism of iron, copper, and zinc in PKU mice.