Glossary of terms

Apgar
Test given to infants at one minute and five minutes after birth. Measures activity, pulse, grimace (reflex irritability), appearance, and respiration. A score of 7-10 is normal.

Arginase - ARG
The enzyme that catalyzes the conversion of arginine, a non-essential amino acid, to ornithine and urea.

Argininosuccinate Synthetase Lyase - ASL
The enzyme that catalyzes the conversion of citrulline to argininosuccinate.

Argininosuccinate Synthetase - ASS
The enzyme that catalyzes the conversion of argininosuccinate to arginine.

Blood chemistry
Ammonia level is one of the blood chemistry tests. Normal is generally considered 0-50 μmol/L .

C-reactive protein
A test that measures the concentration of a protein in serum that indicates acute inflammation. Normally there is no C reactive protein in the blood.

Carbamyl Phosphate Synthetase I - CPS
The enzyme that catalyzes the conversion of ammonium and carbonate ions to carbamyl phosphate.

Catabolism
A metabolic process that burns energy.

Chromatin
Substance that gives the nucleus its granular appearance.

Citrulline
Synthesized from ornithine and carbamyl phosphate. Citrulline is then converted back to arginine.

Citrullinemia type II
An adult-onset defect in the mitochondrial calcium-dependent transporter, resulting in a deficiency in ASS (argininosuccinate synthetase) and a build up of ammonia in the bloodstream and tissues of the body.

Combativeness
Tendency to fight.

Complete Blood Count - CBC
Measures red cells, white cells, platelets, etc., in the blood.

Cytoplasm
Gelatinous solution that contains microtubules that serve as the cells' cytoskeleton and organelles (little organs).

Cytosol
The cytosol (as opposed to cytoplasm, which also includes the organelles) is the internal fluid of the cell, and a large part of cell metabolism occurs here. Proteins within the cytosol play an important role in signal transduction pathways, glycolysis, and act as intracellular receptors and ribosomes.

back to toptop

Delusion
An irrationally held belief.

Delirium
An acute mental disorder characterized by delusions, hallucinations, disorientation or extreme excitement.

Dialysis
A process by which blood is cleansed artificially.  Hemodialysis and peritoneal dialysis are the principal methods.  (Also see ECMO/HD)

Disorientation
Loss of awareness of space, time or personality.

ECMO/HD
A pump-driven dialysis technique using a combination of extracorporeal membrane oxygenation (ECMO) and hemodialysis (HD).

Golgi complex
Consists of a series of flattened sacs. Functions include synthesis and packaging of materials for transport in the cell.

Group B Strep - GBS
The most common cause of sepsis (infection of the blood) and meningitis (infection of the fluid and lining around the brain) and is a frequent cause of newborn pneumonia. GBS can cause overwhelming infection and death in a very short time span.

Hallucinations
A false perception of something that is not there.  May affect any of the senses (sight, hearing, touch, taste or smell).

Hemizygote
Nucleus, cell or organism that has only one of a normally diploid set of genes.

Hemodialysis
The process of filtering waste products out of the body and restoring normal constituents to the blood through a dialysis machine.

Heterozygote
An individual with two different alleles at a given locus on a pair of homologous genes. Seen in x-linked diseases.

Homozygote
Two mutant alleles (one inherited from each parent) and no normal alleles. Autosomal recessive diseases occur only in this situation.

Hyperammonemia
A symptom of the inability to break down protein into urea, hyperammonemia (an abnormally high level of ammonia in the blood) is a dangerous condition that, left untreated, will result in brain damage, coma and eventually, death. 

Hyperornithemia, Hyperammonemia, Homocitrullinemia Syndrome - HHH
A defect in the membrane transporter of ornithine.

back to toptop

I/T neutrophil ratio
The ratio of immature to total neutrophil cells. Immature cells are higher in the presence of infection.  Maximum ratio to exclude sepsis is 0.16.

Incidence
Number of new cases of a condition, death or injury during a specified period of time, such as a year.

Lethargy
Mental and physical sluggishness.

Liver enzymes
An initial step in detecting liver damage is a simple blood test to determine the presence of certain liver enzymes in the blood. Normally, these enzymes reside within the cells of the liver. However, when the liver is injured, these enzymes are spilled into the blood stream.

Among the most sensitive and widely used of these liver enzymes are the aminotransferases. They include aspartate aminotransferase (AST or SGOT) and alanine aminotransferase (ALT or SGPT). These enzymes are normally contained within liver cells. If the liver is injured, the liver cells spill the enzymes into the blood, raising the enzyme levels in the blood and signaling the liver damage.

Lysinuric Protein Intolerance - LPI
Defects in the membrane transporter mechanism for the amino acids, lysine, arginine, and ornithine.

Microfilaments
Provide structural support to the cell.

Microtubule
Made up of proteins and adds rigidity to the cells.

Mitochondria
Primary function is the production of ATP (adenosine triphosphate).

N-acetylglutamate Synthase - NAGS
The enzyme that acts as a co-factor in the catalysis of glutamate to phenylacetylglutamate, a compound that is excreted in urine.

Nuclear envelope
Composed of two layers. The outer membrane connects with the endoplasmic reticulum.

Nucleolus
Located within the nucleus, its function is the production of ribosomes.

Nucleus
Located at the center of the cell and is surrounded by cytoplasm. Contains DNA in the form of chromosomes. Primary functions are cell division and control of genetic information.

Orotic acid
A chemical overproduced in an alternative pathway when there is a block in the urea cycle. Excessive amounts of orotic acid are usually found in OTC (ornithine transcarbamylase) deficiency, Citrullinemia, and oftentimes in Argininosuccinic Aciduria. Orotic acid determination is useful in delineating the cause of hyperammonemia.

Orphan drugs
Pharmaceutical products given special development status to encourage the research and development of novel treatments for disorders that are rare. 

Ornithine Transcarbamylase - OTC
The enzyme that catalyzes the conversion of ornithine to carbamyl phosphate.

Peritoneal dialysis
A process that uses the lining of the patient’s peritoneum to filter out waste products and replenish normal constituents.

Plasma membrane
Can include or exclude select molecules and also control movement of molecules into or out of spaces.

Platelets
The smallest formed elements of the blood. They are essential for clotting. Normal range is 130,000-400,000/μL. Decreased levels indicate immune system failure.

Prevalence
The proportion of individuals at any one time that have a particular disease.

Prognosis
An assessment of the future course and outcome of a patient’s illness.

PROM
Premature rupture of membranes (PROM) is an event that occurs during pregnancy when the sac containing the developing baby (fetus) and the amniotic fluid bursts or develops a hole prior to the start of labor.

Psychoses
A group of mental disorders that feature a loss of touch with reality.

Ribosomes
Primary function is to produce proteins.

Rough endoplasmic reticulum
Found within the organelles, it is coated with ribosomes.

Smooth endoplasmic reticulum
Found within the organelles and does not contain ribosomes.

Unstable gait
Loss of balance when walking.

Urea cycle disorders
A group of inherited metabolic disorders that prevents the human body from breaking down protein into non-toxic urea, resulting in the build up of toxic intermediate ammonia levels.

Vacuole
Isolates water from the cytoplasm.

White Blood Count - WBC
Cells that fight infection in the body. Normal range is 3,800-10,800/μL. Elevations over 10,000 indicate the presence of infection.

 

back to toptop