Diseases b Flashcards
1
Q
What is Cushing’s syndrome?
A
- Hypercortisolism bc of adrenal hyperplasia (too much ACTH)
- Symptoms: obesity, hypertension, osteoporosis and diabetes
2
Q
What is Cushing’s disease?
A
- Caused by a pituitary tumor that overproduces ACTH
- Commonly men age 40-59
3
Q
What is Androgen insensitivity syndrome?
A
- Due to a defect in androgen receptor
- Mutations of the androgen receptor gene
- XY patients develop testes and females external genitalia and vagina (no uterus)
- Abnormal male phenotypic development, no secondary sex characteristics. May look like woman.
- AR plays crucial role in post-meiotic perm production, so mutation may lead to infertility.
4
Q
What is Kennedy’s disease?
A
- Spinal and Bulbar Muscular atrophy)
- Adult-onset neurodegenerative disease in males -Slow progressive muscle weakness and atrophy caused by the expansion of a CAG repeat in androgen receptor gene
5
Q
What mutation is a major cause of prostate cancer?
A
-Androgen receptor has a central role in the normal growth/development of the prostate gland & carcinogenesis
6
Q
What causes cholera?
A
- Cholera Toxin: covalently bonds & blocks the inactivation of GSα. Cannot hydrolyze GTP (on)
- Symptoms: massive diarrhea and dehydration (water flow from blood to intestine lumen)
7
Q
What is pertussis?
A
- Whooping cough toxin modifies inhibitory complex Giα, which prevents the release of GDP (always OFF).
- Symptoms: respiratory tract is infected, and coughing can lead to vomiting and dehydration
- Treatment: antibiotics and hydration therapy
8
Q
What is diabetes mellitus type 1?
A
-Autoimmune disease with destruction of insulin-secreting beta cells in the pancreas (decreased insulin secretion)
9
Q
What is diabetes mellitus type 2?
A
- Insulin resistance, impaired signaling and action
- Primarily caused by obesity
- Resistance leads to more secretion, but it’s insufficient
- High levels of glucagon worsens hyperglycemia by increasing glucose production in the liver.
10
Q
What is cardiac hypertrophy?
A
- Heart adaptive response to cardiac disease by increasing in cell size and up-regulating fetal cardiac genes
- Ater myocardial infarction, cardiac arrhythmia, -Treatment: inhibitors of Calcineurin (cyclosporin A, FK506)
11
Q
What is hypertrophic cardiomyopathy?
A
-Sustained hypertrophy (normally in L-ventricle) -Can lead to myocellular disarray, increased fibrosis, dilated cardiomyopathy, heart failure, & death.
12
Q
What is Familial hypertrophic cardiomyopathy?
A
- Leading cause of sudden cardiac death in young athletes often caused by mutations in contractile proteins in sarcomeres
- It is associated with increased intracellular Ca2+ released to maintain contractility, but this triggers a hypertrophic response of cardiomyocytes)
13
Q
What are Neuro-cardio-facial-cutaneous syndromes (NCFC)?
A
- Developmental disorder due to germline mutations in Ras signaling cascade
- Symptoms: psychomotor delay, cardiac abnormalities, short stature, facial dysmorphism, skin defects, increased cancer risk.
- Similar mutations in: Neurofibromatosis Type 1, Noonan syndrome, Leopard syndrome, Costello syndrome.
14
Q
What is Familial adenomatous polyposis (FAP)?
A
- Causes numerous polyps in the colon and rectum, which can progress to malignant forms
- Caused by APC mutations, which lead to β-catenin accumulation and abnormal gene transcription
15
Q
What is GRTH syndrome?
A
- Dominant negative mutation in ligand binding domain that cause general resistance to thyroid hormone by inhibiting binding.
- High circulating levels of thyroid hormones
- Hearing defects, mental retardation, learning disabilities, emotional disturbance
16
Q
What is Grave’s disease?
A
- Hyperthyroidism
- Hereditary overactivity of the thyroid gland
- Thyroiditis: inflammation of the thyroid gland
17
Q
What is a thyroid storm?
A
- Thyrotoxic crisis
- Acute, life-threatening because of excessive release of thyroid hormones
- Symptoms: fever, dehydration, rapid heart rate, irregular heart beat, heart failure, nausea, vomiting, weakness, confusion, disorientation
18
Q
What is Hypocalcimic Vitamin D -resistant Rickets?
A
-Mineralization defect due to mutations in VDR
19
Q
What is Inclusion-cell Disease, (I-Cell)?
A
- Rare, inherited lysosomal storage disorder
- Lack of hydrolases leads to build up of materials because of faulty targeting of lysosomal enzymes (no GlcNAc-phosphotransferase)
- Symptoms: Failure to thrive, developmental delays, abnormal skeletal development, coarse facial features, & restricted joint movement
20
Q
What is Fabry’s disease?
A
- X-linked recessive lysosomal storage disease caused by a deficiency in a-galactosidase
- Results in the accumulation of ceramide trihexoside
- Peripheral neuropathy of hands/feet, renal disease, angiokeratomas; cardiac, cerebral, & vascular involvement
21
Q
What is Fanconi’s anemia?
A
- Autosomal recessive disorder
- Defective DNA repair causes increased chromosomal breakage & deletions
- Sensitivity to alkyalting agents,
- Abnormal/absent thumbs, kidney malformations, hypogonadism, microcephaly, & high fetal Hb, apastic anemia that can lead to AML
- Pancytopenia: cured with bone marrow transplant
22
Q
What are some characteristics of squamous cell carcinoma?
A
- Strongly related to smoking
- Presents with centrally located mass
- Ectopic parathyrid hormone-related peptide production
- Cough with blood, hypercalcemia
23
Q
What is Pernicious anemia?
A
- Megaloblastic anemia caused by loss of gastric parietal cells, which are responsible for the secretion of intrinsic factor
- Due to an antibody against parietal cells
- This leads to vitamin B12 deficiency
- Fatigue and numbness of lower extremities
24
Q
What causes CML?
A
- Abnormal gene product due to Philadelphia chromosome (translocation 9:22) produces a bcr-abl fusion protein
- bcr-abl: act as a constitutively active tyrosine kinase to promote leukemia growth
- Increased neutrophils & metamyelocytes
- Treated with Gleevec (tyr-kinase inhibitor)
25
What is B-Thalassemia major?
- Condition caused by absence of both B-chains
- Severe hemolysis, ineffective erythropoiesis, , iron overload -> iron deposits
- Requires frequent blood transfusion
26
What is congenital adrenal hyperplasia (CAH)?
- Deficiency in enzymes for adrenocortical steroid synthesis. Female pseudo-intersexuality/ female pseudohermaphrodism.
- Excess androgens -> Masculinization of tissue
- 11β-Hydroxylase deficiency: hypertension
-21β-Hydroxylase deficiency: (most common) no aldosterone -> hypotension & hypovolemia. Deficits in glucocorticoid & mineralcorticoids. Increase in sex steroid production.
27
What happens in the case of 17-β-Hydroxylase deficiency?
- Male pseudo intersexuality
- Enzyme normally converts androstenedion to testosterone
- Small penis & scrotum, w/ normal male organs
28
What happens in the case of 5-a-Reductase deficiency?
- Male pseudo-intersexuality
- Enzyme coverts testosterone to DHT for development of male genitalia in normal men
- XY individuals have no external male genitalia until puberty
29
What is Klinefelter's syndrome?
- 47XXY, males phenotype
- Male infertility because of non-functional testes
- Low testosterone levels, and increase of gonodotropin levels (FSH and LH) due to lack of negative feedback
30
What is obstructive liver disease?
- Obstruction of intrahepatic or extrahepatic bile ducts with subsequent liver injury
- Conjugated hyperbilirubinemia, increase in urine bilirubin, decrease in urine urobilinogen
31
What is Turner's syndrome?
- 45XO, infertile women
- Ovarian dysgenesis "streak ovary"
- Presents with poorly developed 2ry sexual characteristics, amenorrhea, heart disease, short
32
What is McArdle's disease?
- Glycogen storage disorder
- Glycogen phosphorylase is deficient in muscle
- Onset during adolescence
- Muscle cramping, rapid fatigue, poor endurance
33
What happens in the case of 17-a-Hydroxylase deficiency?
- Female lack amenorrhea, lack secondary characteristics, and have hypertension
- The elevated levels of aldosterone lead to hypokalemia.
