proteins Flashcards
kwashiorkor or marasmus
- <1 year old
- due to low calorie intake
- severe growth retardation
- severe reduction in body weight
- shrunken abdomen and subcutaneous fat not preserved
- prominent ribs
- voracious feeder
- no fatty liver
- oedema not present
- an old man like face
- no hair changes noted
- dry and wrinkled skin
- alert but irritable
- requires adequate amount of protein, fat, and carbohydrate
marasmus
immunoglobulin
- (?) is the most abundant antibody in plasma and lymph
- (?) is the main antibody in mucous secretion
- (?) is the first antibody that appears in response to antigenic stimulation
- (?) is the antibody for allergic and anaphylactic reactions
- (?) is present mostly on the surface of B cells.
- IgG
- IgA
- IgM
- IgE
- IgD
proteins
- Proteolytic fragments of collagen I formed during bone resorption
- CTX is a biochemical marker of bone resorption that can be detected in serum and urine
cross-linked c-telopeptides
complement
second most abundant
C4
CLINICAL SIGNIFICANCE
* decreased in hepatic damage, acute-phase inflammatory response, and tissue necrosis
- a low level is a sensitive marker of poor nutritional status
- increased in patients receiving steroids, in alcoholism, and in chronic renal failure
prealbumin
- Single polypeptide chain that is a component of the light chain of HLA class I
- Freely filtered by the glomerulus and completely reabsorbed
- Increased: SLE, RA, Renal Failure, Multiple Myeloma, HIV
B2-microglobulin
globulin
Most important function: inhibition of the protease neutrophil elastase Abnormal form of AAT can also accumulate in the liver and cause cirrhosis Major component of a1-globulin band → deficiency of AAT seen as lack of an a1-globulin band on SPE
alpha-1-antitrypsin
globulin
- Natural defense and enhanced immune response by cell lysis
- Synthesize by the liver
complement
globulin
- Synthesized by the developing embryo and fetus, thought to protect the fetus from immunologic atack by the mother
- No known function in normal adults
Clinical significance
* Elevated AFP. neural tube defects (e.g. spina bifda). presence of twins
- Low AFP: increased risk for Down syndrome (trisomy 21)
- Tumor marker for hepatocellular carcinoma, some testicular carcinomas
alpha-1-fetoprotein
significant proteins
- It is a group of proteins consisting of α1, α2, β, and γ fractions.
- It is usually measured by subtracting the value of serum albumin from the total protein concentration.
- Method for measurement: Indirect method
globulin
classification
- Contain peptide chains composed of amino acids linked by peptide bonds.
- These may be fibrous (fibrinogen, troponins, collagen) and globular (hemoglobin, plasma proteins, enzymes, peptide hormones) in shape
simple proteins
proteins
- cysteine protease inhibitor
- New marker for changes in GFR
- Used for screening and monitoring kidney dysfunction
cystatin c
alpha-2-macroglobulin
pitting edema
hypoalbuminemia
globulin
- glycoproteins produced by plasma B cells
- Increased: Humoral response, Autoimmune disorder, Allergic reaction
- Decreased: Hypogammaglobulinemia,
Immune deficiency
immunoglobulins
proteins
- Glycoprotein produced by fetal membranes responsible for the cellular adhesiveness of placenta and membranes to the decidua.
- Fetal (?) is produced at the boundary between the amniotic sac and the decidua (the lining of the uterus) and functions to maintain the adherence of the placenta to the uterus.
- Test for assessment of the risk for preterm delivery in women between 24 to 35 weeks gestational age
fibronectin
alpha-2-macroglobulin
due to the loss of anti-thrombin III
hypercoagulate state
globulin
- Autosomal recessive
- Decreased levels of ceruloplasmin
Excess storage of copper in various organs
* Liver → hepatic cirrhosis
- Brain → neurologic damage
- Cornea → Kayser-Fleischer rings
Other laboratory findings
* Total serum copper
- decreased Free serum copper increased
- Urinary copper increased
wilson’s disease
alpha-2-macroglobulin
may result in fatty casts in the urine
hyperlipidemia and hypercholesterolemia
globulin
- Transports lipids (HDL)
CLINICAL SIGNIFICANCE
* decreased positive risk factor for atherosclerosis and positive risk factor for Carbohydrates
alpha-1-lipoprotein
formula for globulin
total protein - albumin
globulin
- Copper-containing (contains >90% of total serum copper)
- Used in the diagnosis of Wilson’s disease
ceruloplasmin
- Protein present in the highest concentration in serum
Functions:
* Provide nearly 80% of colloid osmotic pressure (COP) of intravascular fluid
- buffers pH
- binds to various substances in blood
- Negative acute-phase reactant
albumin
protein
- Insoluble fibrous protein aggregates form due to alteration in the secondary structure known as B-pleated sheets
- Low (?) and High Tau protein: suggestive of Alzheimer’s Disease
- Abnormal (?) and Tau: Dementia
amyloid