Tissue Proteins & Body Fluids

Question 1

1. Major proteins of ECM include
2. Structural protein include?
3. How many types of collagens? Composed of how many polypeptide chains?
4. Collagen found in:
   Skin
   Bone

Answer 1

1. Collagen
   Elastin
   Fibrillin
   Fibronectin
   Laminin
   Proteoglycans
2. Keratins
3. 19 types of collagen—-30 distinct polypeptide
4. Skin—-type I
   Bone—-type II

Question 2

1. Collagen has a ____ structure?
2. 1/3rd of amino acids are contributed by?
3. Rigidity of collagen is due to?
4. Strength is due to covalent crosslinkages between?
5. Predominantly collagen is composed of which 2 amino acids?

Answer 2

1. Triple helical
2. Glycine (every 3rd amin o acid in collagen is glycine)
   -polymer of glycine-led tripeptide
3. Proline & hydroxyproline
4. Lysine & hydroxylysine
5. Glycine & proline (Girl Power

Question 3

1. Why wrinkles and sagging of skin with age?
2. Collagen is synthesized in?
3. Precursor form of collagen?
   Converted to procollagen in?

Answer 3

1. Collagen production declines with age
2. In fibroblasts & related cells:
   Osteoblasts
   Chondroblasts
3. Preprocollagen
   - in ER

Question 4

What are the collagenopathies?
Name them?

Answer 4

Inherited Diseases related to gene mutations linked with collagen formation

1.Ehlers-Danlos syndrome (EDS)
2.Alport syndrome
3.Osteogenesis imperfecta (brittle bone disease)
4. Epidermolysis bullosa

Scurvy (vit.C deficiency)
—-NOT GENETIC
also related to improper collagen formation ( bcz vit. C needed for post translational modification of collagen)

Lathyrism
(Bone deformities)

Question 5

1. What is Ehlers-Danlos Syndrome?

Answer 5

• inherited collagenopathy
  (Defective collagen synthesis)

Symptoms

• hyperextensibity of skin
• abnormal tissue fragility

Symptoms such as
joint hypermobility,
stretchy skin,
easy bruising,
chronic pain,
and fragile blood vessels.

Question 6

1. What is Alport’s syndrome?

Answer 6

Alport Syndrome is a genetic disorder
that affects the kidneys and can cause hearing loss and eye abnormalities.

Cause
-defect in collagen Type IV
In the basement memberane of renal glomeruli

Symptoms
-hematouria
- lens dislocation
- hearing loss

Question 7

1. What is osteogenesis imperfecta?

Answer 7

Osteogenesis Imperfecta, also known as brittle bone disease, is a genetic disorder that causes fragile bones that break easily.
- due to decreased formation of collagen

Question 8

What is Epidermolysis Bullosa?

Answer 8

Epidermolysis Bullosa is a rare genetic disorder that causes the skin to be extremely fragile and prone to blistering.
- skin breaks & blisters

Causes
Alterations in type VII collagen (7)

Question 9

What is lathyrism?

Answer 9

Lathyrism is a neurological disorder caused by the excessive consumption of the legume called Lathyrus sativus (kesari dal), also known as grass pea.
It can lead to paralysis and other motor impairments.

Cause
Toxic compund in it
B-oxalyl aminoalanine
(BOAA) interferes with
Cross linking of lysine amino acids in collagen
- BOAA inhibits—-lysyl oxidase

Question 10

Abormailities associated with elastin?

Answer 10

Williams syndrome
genetic disorder

It is caused by a deletion of genetic material on chromosome 7.

• impairment in elastin synthesis

Symptoms
People with Williams syndrome often have distinct facial features, including a
broad forehead,
a flattened nasal bridge,
a small upturned nose,
full cheeks,
and a wide mouth with full lips.
- connective tissue and CNS are effected

Also elastin synthesis is decreased in aging of skin and pulmonary emphysema

Question 11

What is marfan’s syndrome?

Answer 11

Marfan syndrome is a genetic disorder that affects the connective tissue in the body.

Symptoms
It can cause various issues, such as
long limbs,
a tall stature,
heart problems, and
eye abnormalities.
- *hyperextensibility of joints

Cause
Mutation in the gene for fibrillin (found in myofibrils)
On chromosome 15

Question 12

1. What is fibronectin?
2. Why tumor cells can do metastasis?
3. Keratin is hard due to?
   Structure of keratin?

Answer 12

Fibronectin is a glycoprotein that plays a crucial role in cell adhesion and the maintenance of the extracellular matrix.
It helps cells attach to their surrounding environment and is involved in various biological processes, including wound healing and embryonic development.

2. Bcz they are deficient in fibronectin
3. Disulfide bonds
   3 polypeptides in a-helical structure

Question 13

1. What is sarcopenia?
2. Largest protein known?
3. The largest gene?
4. Muscular dysrophy is due to ?

Answer 13

1. Sarcopenia is a condition where there is a loss of muscle mass and strength as a person ages. It can lead to decreased mobility and increased risk of falls.
2. Titin
3. That codes for dystrophin
   (2300 bp)
4. Mutation in the gene on chromosome X That codes for dystrophin

Question 14

1. What are the types of diseases due to protein misfolding
2. Which fluid is not a biological fluid?
3. Why is milk white?
4. What are the major proteins found in milk?
5. Lipids in milk are mostly?
6. If milk is acidified, casein is precipiatated at?
   The supernatant fluid will contain?
7. Milk is poor in which
   minerals
   Vitamins

Answer 14

1. Prion disease (infectious)
2. Amyloidosis (non-infectious)
3. Serum (bcz prepared in laboratory)
4. Milk appears white because it contains tiny particles called casein micelles, calcium caseinate micelles that scatter and reflect light, giving it a white color.
   The proteins and fats in milk also contribute to its creamy appearance.
5. Casein (milk casein—phosphoprotein)
   Lactalbumin
6. Triacylglycerols
7. Isoelectric point (pH=4.7)
   - whey proteins

7.
Poor source of minerals :
Iron & copper
Deficient in Vitamins:
Vitamin C

Question 15

What are prion diseases?

Cause? Alteration in?

Diseases caused by prion proteins?

Answer 15

Prion diseases are a group of rare and fatal neurodegenerative disorders caused by abnormal proteins called prions.
They can affect both humans and animals and lead to progressive damage to the brain and nervous system.

Cause
Prion proteins (infectious)
-altered tertiary structure (replacement of a-helices by B-sheets)

Diseases

Humans:________________________

Transmissible spongiform encephalopathies (TSEs)
( accumulation of abnormal (misfolded) prion proteins in the brain, leading to the formation of sponge-like holes and tissue damage)

Creutzfeldt Jacob disease
- (degenerative neurological disorder that belongs to the group of transmissible spongiform encephalopathies (TSEs).
It is caused by the accumulation of abnormal prion proteins in the brain, leading to the progressive destruction of brain cells. )

ANIMALS:______________________

Scrapie
Scrapie is a disease that affects sheep and goats. It is caused by abnormal proteins called prions and can lead to neurological damage.

Bovine spongiform encephalopathy
Bovine spongiform encephalopathy (BSE), also known as “mad cow disease,” is a neurodegenerative disease that affects cattle.
It is caused by the accumulation of abnormal prion proteins in the brain.
BSE can lead to behavioral changes, difficulty in coordination, and ultimately, death

BSE is not contagious to humans, but consuming infected meat products can lead to a human form of the disease called variant Creutzfeldt-Jakob disease (vCJD)

Question 16

What is Kuru?

Answer 16

A prion disease

Kuru is a rare and fatal neurodegenerative disease that was once prevalent among the Fore people in Papua New Guinea.

It is caused by the consumption of human brain tissue infected with abnormal prion proteins (cannibalism).

Kuru is characterized by progressive neurological symptoms, such as tremors and loss of coordination.

Question 17

1. What is amyloidosis?
2. How many proteins are involved in amyloidosis?
3. What is the disease caused by amyloidosis?
   Causative agent? Formed by?

Answer 17

Amyloidosis is a condition where abnormal proteins (misfolded) ,altered with B-sheets) called amyloids build up in different organs of the body.

2. 15 different proteins
3. Alzheimer’s disease
   a neurodegenerative disorder that primarily affects memory and cognitive function.
   It is the most common cause of dementia, and symptoms include memory loss, confusion, and difficulty with daily tasks.
   - accumulation of amyloids in the form of amyloid plaques

• causative agent:
  B-amyloid
  Formed by apolipoprotein E
  (a-amyloid—-B-amyloid)

Question 18

1. CSF originates in the?
2. Returns to blood thru?
3. Which organ has no lymphatic system?
4. How is CSF collected?
5. What is tuberculosis meningitis?
   What happens to CSF in tuberculosis meningitis?

What happens in case of brain tumor?

Answer 18

1. Choroid plexus
2. Returns thru arachnoid villi

3 Brain
So CSF drains into ventricular system

4. By spinal puncture in lumbar region
   Btw 3rd & 4th or 4th or 5Th lumbar vertebrae
5. Tuberculosis meningitis is a serious infection that affects the membranes covering the brain and spinal cord. It is caused by the bacteria Mycobacterium tuberculosis and can lead to symptoms such as headache, fever, neck stiffness, and confusion.

• CSF—–Opalescent & slightly yellow colored
  Also
  Total cell count & protein content—-increased
  Glucose conc—-Decreased

6. Brain tumor:
   Total cell count—-unchanged
   protein content —-increased

Question 19

1. What is amniocentesis?
2. How amniotic fluid can assess neural tube defect?
3. How amniotic fluid can assess fetal maturity?
4. How amniotic fluid can assess lung maturity?

Answer 19

Amniocentesis is a procedure where a small amount of amniotic fluid is extracted from the uterus during pregnancy.
It is usually done to check for genetic disorders or other abnormalities in the developing fetus.

2. By increased levels of a-fetoproteins
3. Staining of fats cells +
   Estimation of creatinine conc
   (>1.6 mg/dl——fetal maturity)
4. Lecithin/sphingomyelin ratio
   (2:1 or >——lung maturity)

Question 20

What is transudate & exudate pleural fluid?

Answer 20

Transudate pleural fluid
refers to a type of fluid that accumulates in the pleural space due to an imbalance in fluid pressure.
Observed in:
-nephrotic syndrome( due to low osmotic pressure in plasma)
- congestive cardiac failure
(Increased hydrostatic Pressure)

It is usually a clear and watery fluid, low in protein content.
- no clot
- no inflammation
- ratio of protein content < 0.5
- specific gravity < 1.015

Exudate pleural fluid
is a type of fluid that accumulates in the pleural space due to inflammation or infection.
Observed in;
Tuberculosis
Pneumonia
Rheumatoid arthritis
Lung cancer

It is often cloudy or thick and contains a higher protein content compared to transudate fluid.

• ratio of protein content > 0.5
• specific gravity > 1.015

Question 21

1. What is aqueous humor?
2. What happens when blockage to aqueous flow?

Answer 21

Aqueous humor is a clear fluid that fills the front (anterior) portion of the eye, between the cornea and the lens.
It helps maintain the shape of the eye and provides nutrients to the surrounding tissues.

–maintains intraocular pressure
–secretes by ciliary body

2. Glaucoma
   Glaucoma is a condition that affects the eyes and can lead to vision loss. It occurs when there is increased intraocular pressure, damaging the optic nerve.