Abnormal: Differing from normal.
Amino Acids: Amino acids combine to form proteins and when proteins are digested amino acids remain – amino acids are either essential (obtained through the diet) or non-essential (made by the body from the essential amino acids).
Amniotic Fluid: The fluid surrounding the fetus inside the uterus.
Arginine: Non-essential amino acid (made only by the urea cycle).
Aspartate: Non-essential amino acid (made only by the urea cycle).
Carrier: Individuals with one abnormal gene in their gene pair. These individuals do not show evidence of the disorder.
Chronic (or Chronically): A situation or disease with a long duration.
Citrulline: An amino acid not used in protein made by the urea cycle.
Concentrations: The level or amount of a substance.
Connective Tissue: Tissue that surrounds other tissues and organs in the body.
Conversion: A change from one state to another.
Crisis: A negative change in the physical and/or mental well-being of a person.
Defects: An abnormality.
Deficiency: A lower amount than necessary for functioning.
Developmental Disabilities: A chronic mental or physical impairment that results in decreased ability of an individuals to reach appropriate age level developmental goals.
Disease: Deviation from a normal state of physical or mental health caused by the body’s response to the environment and/or infective substances.
Disorder: An abnormal physical or mental condition.
Elevation: An abnormal increase in a substance.
Enzymatic Assay: Examination of the enzyme. (Also see: assay)
Experimental: Information based on a scientific study.
Formation: The act of taking shape or form.
Homocitrullinuria or Homocitrulline: A chemical variant of citrulline.
Hyperammonemia: Elevated levels of ammonia in the blood.
Hyperornithinemia: A chemical variant of ornithine.
Intellectual Development: The ability to gain knowledge.
Investigation: An in-depth study.
Liver: A large vascular organ in the body that causes important changes in substances in the body in order for the body to use these substances.
Lysine: An essential amino acid.
Metabolic Pathway: The sequence by which the chemical changes in living cells provide energy for vital processes in the body, resulting in new material mitochondria – found inside the cell and produce energy for the cell.
Molecule: A combination of tiny, invisible particles in the body that are bonded together.
Partial Activity: Not completely active, may be missing vital components.
Prenatal: Before birth.
Primarily: Occurring first, of most importance.
Protein: Essential to all living cells, simplified by body processes to simple alpha-amino acids.
Red blood cells: A type of cell in the body that carries oxygen to the body’s tissues.
Rescued from crisis: Removed from harm or a dangerous situation.
Seizures: A temporary change in brain performance due to abnormal electrical activity of a specific group of cells in the brain that either present with sudden muscle contractions, decreased level of consciousness, and several other symptoms.
Self-select: To determine on one’s own either consciously or subconsciously.
Stressful: Having stress, irritation.
Switching Off: To turn off.
Tissue: A group of cells that have a similar structure and function.
Triggering Event: An episode that causes a reaction or illness.
Urea: A product of protein breakdown of amino acids, excreted in the urine.
Urea Cycle: A metabolic process in which waste (nitrogen) from the breakdown of proteins in the body is changed by the liver into a urea, excreted in the urine.
Voluntary muscles: Muscles of the body that a person can control.
Waste: unusable or excess material, lost by breaking down of the body’s tissues.
X-Chromosome: A sex chromosome in both males and females (males have one X-chromosome, XY=male, and females have two X-chromosomes, XX=females).
The Urea Cycle Disorders Consortium (UCDC) is a part of NIH Rare Diseases Clinical Research Network (RDCRN). Funding and/or programmatic support for this project has been provided by the National Institute of Child Health and Human Development (NICHD) and the NIH Office of Rare Diseases Research (ORDR). Read Disclaimer >