PubHealth Final - Env and Nutr pathology

Coenzyme

small, non-protein organic molecule that temporarily binds to enzymes to help in biochemical reactions

Riboflavin (B2) is essential for the production of coenzymes __ and __.

• flavin mononucleotide FMD

• flavin adenine dinucleotide FAD

Niacin (B3) is the precursor for __ and __.

• nicotinamide adenine dinucleotide NAD

• nicotinamide adenine dinucleotide phosphate NADP

Thiamine (B1) acts as a coenzyme in the synthesis of __ and removes __ from amino acids.

• neurotransmitters

• CO2

Thiamine B1 deficiency can cause either __ or __.

• Dry Beriberi

• Wet Beriberi

Dry Beriberi

weakness, nerve degeneration, poor coordination, and loss of nerve transmission

Wet Beriberi

edema, enlarged heart, and heart failure

Thiamine B1 deficiency typically occurs when __ is the only staple.

polished rice

Pellagra is associated with a deficiency in __.

Niacin - Vitamin B3

Pellagra causes the 4D symptoms:

1. Dementia

2. Diarrhoea

3. Dermatitis

4. Death - if untreated

Niacin VitB3 is found in… (6)

• mushrooms

• enriched grains

• fish

• turkey

• chicken

• beef

__ as a main staple can lead to Niacin VitB3 deficiency.

Corn

A deficiency in __ is associated with megaloblastic anemia and nerve degeneration.

Vitamin B12 - cyanocobalamin

Vitamin B12 (Cyanocobalamin) plays a role in…(3)

1. folate metabolism

2. RBC formation

3. maintenance of myelin sheaths

Vitamin B12 (cyanocobalamin) is found in…(3)

1. organ meats

2. seafood

3. dairy products

Folic acid Vit B9 deficiencies are associated with __.

megaloblastic anemia

Folic acid Vit B9 has a major role in __

DNA synthesis

A deficiency in __ is associated with scurvy.

Vitamin C - ascorbic acid

Vitamin C is __ by humans.

NOT made

Vitamin C helps to enhance __.

iron absorption

Vitamin C plays a role in…(3)

1. immune functions

2. collagen synthesis

3. cancer prevention

Vitamin A deficiency is associated with…(3)

1. night blindness

2. infectious disease susceptibility

3. keratinisation

Vitamin A has a role in…(5)

1. vision

2. protein synthesis

3. cell differentiation

4. reproduction

5. growth

A deficiency in __ can lead to the development of Rickets.

Vitamin D - Calciferol

Vitamin D deficiencies are also known to cause __ and __.

• Osteomalacia - softening of bones

• Hypocalcemia - low Ca

V

Vitamin D has a major role in…(2)

• maintaining Ca blood concentration

• bone growth and remodelling

__ plays an important role in maintaining the integrity of cell membranes.

Vitamin E

Vitamin E isa powerful __ and the primary defence against __-__.

• antioxidant

• free-radicals

A deficiency in __ is associated with abnormal blood clotting as it is involved in the synthesis of __ needed for clotting.

• Vitamin K

• blood proteins

Vitamin K also has a role in the synthesis of __.

bone proteins

Basal Metabolic Rate

minimum number of calories required to perform essential, life-sustaining functions while at rest

The hypothalamus stimulates __ which signal an organism to eat, and __ which signal and organism to stop eating.

• feeding cells

• satiety cells

Juvenile-onset obesity

increase in the number of adipose cells

• develops in infancy or childhood

Adult-onset obesity

fewer adipose cells, but they are larger

• if weight gain is continued, the number of adipose cells will increase

A 43 year-old woman is seen by her local physician with a complaint of fatigue and shortness of breath.  Blood tests reveal a decreased red blood cell (RBC) count and an increase in mean corpuscular volume (MCV), consistent with megaloblastic anemia.  A bone marrow biopsy is performed to confirm the diagnosis.  It shows marked hypercellularity, with numerous immature, enlarged cells (megaloblasts). The woman is treated with injections of vitamin B-12, and she eventually resumes her normal activities.

• Why did this woman complain of fatigue and shortness of breath?

Deficiency reduced the production of healthy RBCs capable of properly transporting oxygen to tissues

A 43 year-old woman is seen by her local physician with a complaint of fatigue and shortness of breath.  Blood tests reveal a decreased red blood cell (RBC) count and an increase in mean corpuscular volume (MCV), consistent with megaloblastic anemia.  A bone marrow biopsy is performed to confirm the diagnosis.  It shows marked hypercellularity, with numerous immature, enlarged cells (megaloblasts). The woman is treated with injections of vitamin B-12, and she eventually resumes her normal activities.

• Why did she have a hypercellular bone marrow?

Vit B12 deficiency can cause hypersegmented neutrophils - as immature RBCs and WBCs are stopped from leaving the bone marrow leading to them over-maturing in the bone marrow

A 43 year-old woman is seen by her local physician with a complaint of fatigue and shortness of breath.  Blood tests reveal a decreased red blood cell (RBC) count and an increase in mean corpuscular volume (MCV), consistent with megaloblastic anemia.  A bone marrow biopsy is performed to confirm the diagnosis.  It shows marked hypercellularity, with numerous immature, enlarged cells (megaloblasts). The woman is treated with injections of vitamin B-12, and she eventually resumes her normal activities.

• Why were her bone marrow cells immature and enlarged?

Vitamin B12 deficiency alters RBC synthesis leading to the formation of megaloblasts

A 43 year-old woman is seen by her local physician with a complaint of fatigue and shortness of breath.  Blood tests reveal a decreased red blood cell (RBC) count and an increase in mean corpuscular volume (MCV), consistent with megaloblastic anemia.  A bone marrow biopsy is performed to confirm the diagnosis.  It shows marked hypercellularity, with numerous immature, enlarged cells (megaloblasts). The woman is treated with injections of vitamin B-12, and she eventually resumes her normal activities.

• Why was she treated with injections of vitamin B-12?

She was suffering from vitamin B12 deficiency resulting in megaloblastic anemia. Administering B12 allows for RBC synthesis to return to normal

Megaloblasts

RBC precursors that are large, immature, and poorly transport oxygen

A 63 year-old woman is seen by her local doctor for back pain.  An x-ray of her spine shows several collapsed vertebrae.  Blood tests reveal an increase in calcium and a decrease in vitamin D.  Levels of parathyroid hormone (PTH) are also increased.  The results of a bone density scan are consistent with the presence of osteoporosis.  Exploratory neck surgery reveals a parathyroid adenoma.  Following removal of the tumor, her blood values of calcium, vitamin D, and PTH return to normal, and her bone density gradually increases.

• What did this woman have back pain?

The woman had osteoporosis which caused a weakening of her bones, particularly in the spine, leading to her vertebrae collapsing

A 63 year-old woman is seen by her local doctor for back pain.  An x-ray of her spine shows several collapsed vertebrae.  Blood tests reveal an increase in calcium and a decrease in vitamin D.  Levels of parathyroid hormone (PTH) are also increased.  The results of a bone density scan are consistent with the presence of osteoporosis.  Exploratory neck surgery reveals a parathyroid adenoma.  Following removal of the tumor, her blood values of calcium, vitamin D, and PTH return to normal, and her bone density gradually increases.

• What caused the collapse of her vertebrae?

The severe loss of bone density, which was caused by excess parathyroid hormone which stimulated osteoclasts to break down bone.

A 63 year-old woman is seen by her local doctor for back pain.  An x-ray of her spine shows several collapsed vertebrae.  Blood tests reveal an increase in calcium and a decrease in vitamin D.  Levels of parathyroid hormone (PTH) are also increased.  The results of a bone density scan are consistent with the presence of osteoporosis.  Exploratory neck surgery reveals a parathyroid adenoma.  Following removal of the tumor, her blood values of calcium, vitamin D, and PTH return to normal, and her bone density gradually increases.

• Why was her calcium level increased?

As a result of the excess PTH which activated osteoclasts. Osteoclasts break down bone to release calcium into the blood.

A 63 year-old woman is seen by her local doctor for back pain.  An x-ray of her spine shows several collapsed vertebrae.  Blood tests reveal an increase in calcium and a decrease in vitamin D.  Levels of parathyroid hormone (PTH) are also increased.  The results of a bone density scan are consistent with the presence of osteoporosis.  Exploratory neck surgery reveals a parathyroid adenoma.  Following removal of the tumor, her blood values of calcium, vitamin D, and PTH return to normal, and her bone density gradually increases.

• Why was her vitamin D level decreased?

• Calcium and Vit D levels are inversely proportional, high Ca levels cause Vit D synthesis to decrease

• Abnormal calcium regulation as a result of high PTH activity resulted in altered vit D metabolism

• Vit D is required to regulate calcium levels

A 63 year-old woman is seen by her local doctor for back pain.  An x-ray of her spine shows several collapsed vertebrae.  Blood tests reveal an increase in calcium and a decrease in vitamin D.  Levels of parathyroid hormone (PTH) are also increased.  The results of a bone density scan are consistent with the presence of osteoporosis.  Exploratory neck surgery reveals a parathyroid adenoma.  Following removal of the tumor, her blood values of calcium, vitamin D, and PTH return to normal, and her bone density gradually increases.

• What was the cause of her osteoporosis?

Excess PTH from the parathyroid adenoma 

A 63 year-old woman is seen by her local doctor for back pain.  An x-ray of her spine shows several collapsed vertebrae.  Blood tests reveal an increase in calcium and a decrease in vitamin D.  Levels of parathyroid hormone (PTH) are also increased.  The results of a bone density scan are consistent with the presence of osteoporosis.  Exploratory neck surgery reveals a parathyroid adenoma.  Following removal of the tumor, her blood values of calcium, vitamin D, and PTH return to normal, and her bone density gradually increases.

• Why did removal of her parathyroid adenoma reverse the loss of bone density?

Its removal stopped excess PTH production allowing bone rebuilding to occur

• The parathyroid adenoma was causing the inappropriate release of PTH → elevated osteoclast activity →  bone loss → high blood Ca levels → disturbed Vit D metabolism