Defects of metabolic processes Flashcards

Question

What is the main treatment for hyperphenylalaninemias?

Answer 1

Restricting dietary intake of phenylalanine-containing foods ## Footnote Phenylalanine is an essential amino acid, so a balance must be maintained.

Answer 2

Fatality ## Footnote Adequate phenylalanine is crucial for normal growth and development.

Answer 3

A phenylalanine-restricted diet for life ## Footnote Life-long treatment is necessary for individuals diagnosed with PKU.

Answer 4

Enzyme substitution therapy ## Footnote This therapy helps reduce phenylalanine levels when dietary restriction is insufficient.

Answer 5

Poor growth, birth defects, microcephaly, and intellectual disability ## Footnote These effects occur regardless of the fetus’s genotype.

Answer 6

Manipulation of the diet ## Footnote This may include substrate restriction, avoiding fasting, and replacing deficient cofactors.

Answer 7

A low-phenylalanine diet ## Footnote Breast milk contains too much phenylalanine to be used as the only nutrient source.

Answer 8

Low-protein food substitutes are introduced ## Footnote This includes low-protein breads and pasta to meet dietary needs.

Answer 9

Three or four slices meet a child's dietary phenylalanine limit ## Footnote Regular bread has a high protein content that contributes to phenylalanine intake.

Answer 10

A warning label ## Footnote Aspartame contains phenylalanine, which is harmful to those with PKU.

Answer 11

A deficiency of fumarylacetoacetate hydrolase (FAH) ## Footnote This enzyme catalyzes the last step in tyrosine catabolism.

Answer 12

Dysfunction of renal tubules, peripheral neuropathy, and progressive liver disease ## Footnote HT1 also has a high risk for developing liver cancer.

Answer 13

Dietary restriction of phenylalanine and tyrosine, and administration of NTBC ## Footnote NTBC inhibits an enzyme upstream of FAH.

Answer 14

Defects in branched-chain α-ketoacid dehydrogenase (BCKAD) ## Footnote MSUD is characterized by a sweet odor in the urine.

Answer 15

Dietary restriction of branched-chain amino acids (BCAAs) ## Footnote Supportive care is also required during crises.

Answer 16

Medium-chain acyl-coenzyme A dehydrogenase (MCAD) deficiency ## Footnote This condition leads to episodic hypoglycemia, especially during fasting.

Answer 17

Accumulation of fatty acid intermediates and exhaustion of glucose supplies ## Footnote This can lead to cerebral edema and encephalopathy.

Answer 18

Avoidance of fasting and ensuring an adequate source of calories ## Footnote Supportive care is needed during periods of nutritional stress.

Answer 19

Catalyzed by long-chain acyl-CoA dehydrogenase (LCAD) ## Footnote This is part of a sequence of steps for fatty acid metabolism.

Answer 20

Advancements in technology ## Footnote This includes the ability to perform inexpensive diagnostic tests.

Answer 21

MCAD deficiency ## Footnote Testing for MCAD deficiency has been added to newborn screening programs in all fifty states of the U.S.

Answer 22

Controlled by long-chain acyl-CoA dehydrogenase (LCAD) ## Footnote This initiates the sequence of steps involved in fatty acid metabolism.

Answer 23

Fatty acid oxidation (FAO) disorders ## Footnote It is characterized by severe liver disease and other systemic complications.

Answer 24

Avoidance of fasting, low-fat diet, medium-chain triglycerides, carnitine supplementation ## Footnote These measures help manage the condition and prevent complications.

Answer 25

Acute fatty liver of pregnancy (AFLP) and HELLP syndrome ## Footnote These conditions are hypothesized to be linked to the fetus's inability to metabolize free fatty acids.

Answer 26

Δ7-sterol reductase (DHCR7) ## Footnote This step is crucial in the production of cholesterol.

Answer 27

Smith–Lemli–Opitz (SLO) syndrome ## Footnote SLO is characterized by reduced cholesterol levels and various congenital anomalies.

Answer 28

3% to 4% ## Footnote This high frequency suggests a higher incidence of SLO than is commonly observed.

Answer 29

Congenital adrenal hyperplasia (CAH) ## Footnote CAH is primarily caused by mutations in the CYP21A2 gene.

Answer 30

* Glucocorticoids (e.g., cortisol) * Mineralocorticoids (e.g., aldosterone) * Androgens (e.g., testosterone) ## Footnote These hormones play crucial roles in various physiological processes.

Answer 31

X-linked recessive pattern ## Footnote These conditions are caused by mutations in the androgen receptor gene.

Answer 32

Zellweger syndrome ## Footnote Symptoms include severe hypotonia and progressive brain disease, typically leading to death in infancy.

Answer 33

Accumulation of undegraded substrates ## Footnote This accumulation results from enzyme deficiencies within lysosomes.

Answer 34

Reduced ability to degrade glycosaminoglycans ## Footnote These disorders can be distinguished by clinical, biochemical, and molecular analyses.

Answer 35

Coarse face, hepatosplenomegaly, corneal clouding ## Footnote It is one of the mucopolysaccharidoses characterized by intellectual disability.

Answer 36

Mucopolysaccharidoses (MPS disorders) ## Footnote MPS disorders include Hurler, severe Hunter, and Sanfilippo syndromes, which are characterized by intellectual disability.

Answer 37

α-L-Iduronidase ## Footnote Clinical features include coarse face, hepatosplenomegaly, corneal clouding, dysostosis multiplex, and intellectual disability.

Answer 38

Coarse face, hepatosplenomegaly, dysostosis multiplex, intellectual disability, behavioral problems ## Footnote Hunter syndrome is an X-linked recessive disorder.

Answer 39

Behavioral problems, dysostosis multiplex, intellectual disability ## Footnote Sanfilippo syndromes are characterized by similar features but differ by enzyme deficiency.

Answer 40

A distinctive pattern of changes in bone ## Footnote Includes a thickened skull, anterior thickening of the ribs, vertebral abnormalities, and shortened and thickened long bones.

Answer 41

β-Hexosaminidase A ## Footnote Clinical features include hypotonia, spasticity, seizures, and blindness.

Answer 42

Splenomegaly, hepatomegaly, bone marrow infiltration ## Footnote Gaucher disease is caused by a deficiency of glucosylceramidase.

Answer 43

Type 1 ## Footnote Type 1 is nonneuropathic and does not involve the central nervous system.

Answer 44

Bone marrow transplantation (BMT) ## Footnote BMT has shown to improve coarse facial features and mitigate neurological deterioration.

Answer 45

To prevent the accumulation of nitrogenous wastes by incorporating nitrogen into urea ## Footnote Urea is subsequently excreted by the kidney.

Answer 46

Accumulation of urea precursors like ammonium and glutamine ## Footnote This can lead to progressive lethargy and coma.

Answer 47

Ornithine transcarbamylase (OTC) deficiency ## Footnote OTC deficiency is X-linked and can cause significant clinical variability.

Answer 48

Transfers electrons to oxygen (O2) and produces ATP ## Footnote OXPHOS consists of five multiprotein complexes located in the inner mitochondrial membrane.

Answer 49

Leads to complex phenotypes due to varying metabolic requirements ## Footnote More than twenty clinical disorders are associated with OXPHOS defects.

Answer 50

Low-protein diet, ammonia scavenging drugs, and sometimes hemodialysis ## Footnote Goal is to prevent hyperammonemia and support normal growth.

Answer 51

Coarse facial features, skeletal abnormalities, hepatomegaly, corneal opacities, intellectual disability ## Footnote Caused by recognition marker deficiency for lysosomal enzymes.

Answer 52

Encodes glucosylceramidase, mutations lead to Gaucher disease ## Footnote More than 400 mutations have been identified in this gene.

Answer 53

Autosomal recessive pattern

Answer 54

Electron transfer flavoprotein (ETF) and ETF-ubiquinone oxidoreductase (ETF-QO)

Answer 55

* Hypotonia * Hepatomegaly * Hypoketotic or nonketotic hypoglycemia * Metabolic acidemia

Answer 56

Metabolism of pyruvate proceeds through pyruvate dehydrogenase, the citric acid cycle, and the OXPHOS system

Answer 57

Lactic acidemia

Answer 58

* E1 * E2 * E3 * X-lipoate * PDH phosphatase

Answer 59

The disulfide derivative of the amino acid cysteine

Answer 60

* Cystinuria * Cystinosis

Answer 61

Cystinuria

Answer 62

* Pharmacological amounts of water (4-6 L/day) * Alkalinizing the urine * Chelating agents such as penicillamine

Answer 63

A diminished ability to transport cystine across the lysosomal membrane

Answer 64

A disorder characterized by excessive iron storage

Answer 65

An autosomal recessive disorder of iron metabolism

Answer 66

* Fatigue * Joint pain * Diminished libido * Diabetes * Increased skin pigmentation * Cardiomyopathy * Liver enlargement * Cirrhosis

Answer 67

Reducing the accumulated iron in the body

Answer 68

An X-linked recessive disorder characterized by copper deficiency

Answer 69

* Intellectual disability * Seizures * Hypothermia * Twisted and hypopigmented hair * Loose skin * Arterial rupture

Answer 70

An autosomal recessive disorder caused by excess copper accumulation

Answer 71

* Acute or chronic liver disease * Neurological symptoms * Arthropathy * Cardiomyopathy * Kidney damage * Hypoparathyroidism

Answer 72

* Chelating agents such as penicillamine and trientine * Zinc salts

Answer 73

At least twelve trace elements

Answer 74

Reduced incorporation of isotopes of copper into cells cultured in vitro

Answer 75

Cofactor in various enzymes, including tyrosinase and cytochrome c oxidase

Answer 76

ATP7B ## Footnote ATP7B was cloned in 1993 and is predominantly expressed in the liver and kidney.

Answer 77

Supplying copper to various enzymes and mediating copper efflux into the bloodstream ## Footnote ATP7A redistributes to the plasma membrane to pump copper when its levels are high.

Answer 78

Missense, nonsense, splice site mutations, and large deletions ## Footnote Approximately 15% to 20% of mutations in ATP7A are large deletions.

Answer 79

Occipital horn syndrome ## Footnote This syndrome includes mild intellectual disability and skin laxity.

Answer 80

Copper transport and excretion into the biliary tree ## Footnote ATP7B also aids in incorporating copper into ceruloplasmin.

Answer 81

Autosomal recessive ## Footnote WND is characterized by progressive liver disease and neurological abnormalities.

Answer 82

Intellectual disability, seizures, and early childhood death ## Footnote MND results from a lack of copper and impaired enzyme function.

Answer 83

A defect in the absorption of zinc ## Footnote AE is caused by mutations in SLC39A4.

Answer 84

Growth retardation, diarrhea, immune dysfunction, severe dermatitis ## Footnote Dermatitis typically affects the genitals, buttocks, mouth, and limbs.

Answer 85

High doses of supplemental zinc ## Footnote This treatment is curative.

Answer 86

Transport of copper across the blood-brain barrier ## Footnote ATP7A is crucial for maintaining copper homeostasis in the brain.

Answer 87

After weaning ## Footnote AE can be fatal if untreated.

Answer 88

Indicates increased deposition of hemosiderin, associated with liver damage ## Footnote This can lead to cirrhosis and liver cancer.

Answer 89

They are highly homologous genes responsible for copper metabolism ## Footnote Mutations in ATP7A cause MND, while mutations in ATP7B cause WND.

Answer 90

About 40% ## Footnote This highlights the significance of specific mutations in genetic disorders.

Defects of metabolic processes Flashcards

(118 cards)