O2 Transport and Utilization in Health and Lung Disease
COPDTetrahydrobiopterin Deficiency1 moreSkeletal muscle dysfunction is a frequent and clinically relevant systemic manifestation of Chronic Pulmonary Obstructive Disease (COPD), which is still poorly understood. Therefore, the focus of this study is on the role of a deficit in tetrahydrobiopterin and nitric oxide synthase uncoupling induced by chronic oxidative stress on metabolic and vascular abnormalities in skeletal muscle of patients suffering from COPD.
The Effects of Sapropterin Dihydrochloride Supplementation on in Vivo Redox Status in Patients With...
Classical Phenylketonuria(PKU)This study is an independent sub-study of the protocol titled PKU-016: A double-blind, placebo-controlled, randomized study to evaluate the safety and therapeutic effects of sapropterin dihydrochloride on neuro-psychiatric symptoms in subjects with phenylketonuria (PKU ASCEND). The primary objective of this study is to determine oxidative stress in patients with classical phenylketonuria (PKU) enrolled in PKU-016, using a brain scan (called an HMPAO SPECT) at baseline and 26 weeks, and blood redox biomarkers.
Nutrition Status of Adults Treated With Pegvaliase
PhenylketonuriasConduct a cross-sectional analysis of the nutritional status of individuals with PKU treated with pegvaliase for one or more years or who have followed an unrestricted diet for 6 or more months while on pegvaliase treatment. We will evaluate laboratory markers of nutritional status, including markers of protein and micronutrient nutriture. In addition, a three-day food record and food frequency questionnaire will be obtained to assess protein intake and overall diet quality.
Follow-up of Adult Phenylketonuria (PKU) Patients
Nutritional DeficienciesPhenylketonuriaAdult patients with phenylketonuria (PKU) at the age around 40 years belong to the first patients generation with early treatment of the disease. PKU is caused by an inborn error of the amino acid metabolism and the so far best suitable therapy is an early and strict diet, which is low in phenylalanine. Besides an early and continuously treatment in childhood, the nutritional and medical support during adolescence and adulthood have been suggested to influence the long-term physical health of adult PKU patients. As many adult PKU patients tend to neglect the necessarily strict diet, they do not get a balanced diet. For PKU patients some nutrients, which may be rare in an unbalanced diet, might help to improve health status, physical and neurological performance and quality of life. Information about the longitudinal development of the patients status and the influence of the type of their medical care is not available. In this 5 year follow-up the investigators aim to study the quality of life and the medical, nutritional and psychological status of adult PKU patients, in whom corresponding information has already been collected previously.
Remote Neurocognitive and Psychological Assessment in PKU
PhenylketonuriasPKU is a rare autosomal recessive condition associated with disruption in dopamine synthesis. Although early diagnosis and treatment prevent the severe impairments associated with untreated PKU, individuals with early-treated PKU (ETPKU) nonetheless experience significant sequelae, including impaired working memory and increased risk for anxiety problems. Past research with other clinical populations (e.g., generalized anxiety disorder) suggests that the two phenomena may be linked, with increased anxiety contributing to poorer WM performance. Currently we propose to initiate an exciting new line of research examining the potential relationship between anxiety and WM in ETPKU. The proposed study will also apply remote neuropsychological performance-based assessment to the study of ETPKU and thus overcoming the geographical limitations/challenges associated with recruitment of participants with this rare disease.
Testing of Four Home Phenylalanine Monitoring Prototype Devices
PhenylketonuriasThe objective of this study is to test four home phenylalanine monitoring prototype devices, selected out of a pool of candidates by the National PKU Alliance Scientific Committee.
The Early History of Universal Screening for Metabolic Disorders
PhenylketonuriaGalactosemia1 moreWe are doing this study to learn more about the early history of universal screening for metabolic disorders such as PKU and galactosemia. In particular, we are interested in learning from our past experience to inform our current plans to expand universal newborn screening. Following standard historical research methodology, we will begin with a review of the historical scholarship on PKU and galactosemia, including more general works on mental retardation, genetics, public health screening, and metabolic disorders. We will also obtain scientific publications and archival sources on the early screening and treatment of these disorders. Lastly, we will conduct oral history interviews with key participants in teh early screening and treatment of PKU and galactosemia.
Observational Study of Endothelial Dysfunction in Phenylketonuria
PhenylketonuriaEndothelial DysfunctionThe purpose of this study is to determine whether adolescent and adult patients with phenylketonuria who are on long-term phenylalanine-restricted diet suffer from endothelial dysfunction.
Phenylketonuria and Hyperphenylalaninemia Nutrition Study
Phenylketonuria (PKU) and HyperphenylalaninemiaThe mainstay of PKU treatment is a low-phenylalanine diet (i.e restriction of natural protein), and supplementation with a protein substitute (a mixture of amino acids free from phenylalanine, also containing micronutrients and vitamins) and special low-protein foods, to meet the patient's energy requirements. When diet and treatment is relaxed after childhood, adult and adolescent patients with phenylketonuria are at risk for malnutrition, depending on the compliance with treatment and the intake of amino acid supplements. In this study, nutrition status of patients with PKU and hyperphenylalaninemia is systematically assessed under ongoing current treatment, in relation to Phe-tolerance, compliance with treatment, and psychosocial issues. Study participants do not undergo any specific therapeutic or diagnostic intervention.
Sapropterin Expanded Access Program
PhenylketonuriaThe Purpose of this study is to provide patients with hyperphenylalaninemia (HPA) due to Phenylketonuria (PKU) access to sapropterin dihydrochloride and to collect more information about the safety of the drug in an expanded access program (EAP) until commercial product is available.