Lecture 13

Question 1

a softening of bones in immature mammals due to deficiency or impaired metabolism of vitamin D, phosphorus or calcium, potentially leading to fractures and deformity; among the most frequent childhood diseases in many developing countries.

Answer 1

Rickets

Question 2

family of small cysteine rich cationic peptides. Alpha ______ are highly expressed in neutrophils, beta _______ are secreted by mucosal epithelia. Both are found in saliva and crevicular fluid where they prevent early colonization by pathogens.

Answer 2

defensins

Question 3

Opposes the actions of PTH to decrease calcium levels in the serum.

Answer 3

calcitonin (CT)

Question 4

bone disease usually by 2; normal or high calcitrol, common to observe bone alopecia, multiple milia, epidermal cysts and oligodontia; treated w high dose of calcitrol

Answer 4

Type 2 rickets

Question 5

a softening of the bones, similar to rickets, that can occur in children, but mainly adults.

Answer 5

osteomalacia

Question 6

expression of the TRPV6 calcium channel gene is dependent on _____

Answer 6

Vitamin D3

Question 7

Severe vitamin D3 deficiency is best known to cause

Answer 7

rickets

Question 8

immune mediated disease affecting skin; Vitamin D treatment can help control symptoms; migratory stomatitis in the oral cavity mucosa and tongue are believed to be oral manifestations

Answer 8

psoriasis

Question 9

______ is a plant/fungi form and most commonly found in dietary supplements and many fortified foods; less absorbable, less potent, and shorter acting

Answer 9

ergocalciferol (vitamin D2)

Question 10

produced by the parafollicular cells of the thyroid that decreases Ca2+ levels

Answer 10

calcitonin

Question 11

manifest by age 2 (usually by 6 months); primary defect is in 25(OH)D-1 hydrolase; low circulating calcitrol; treated w massive doses of vitamin D

Answer 11

Type 1 rickets

Question 12

closely related homolog produced by various cells that plays an important role in tooth eruption and endochondral bone formation

Answer 12

PTHrP

Question 13

related antimicrobial peptides are a family of polypeptides found in lysosomes of macrophages and polymorphonuclear leukocytes (PMNs); serve a critical role in mammalian innate immune defense against invasive bacterial infection; broad spectrum antibacterial activity.Have been also studied in terms of a role in periodontal disease.

Answer 13

Cathelicidin

Question 14

Ca2+ levels in serum are sensed by the ______ gland through the _________

Answer 14

parathyroid gland; calcium sensing receptor (CaSR)

Question 15

A pro-hormone which requires metabolic activation to generate the most active chemical form; activation pathway involves a UV-activated step which means that it must either be obtained via the diet or be produced via a sunlight activated step.

Answer 15

Vitamin D3/ cholecalciferol

Question 16

Vitamin D3 plays a major role in control of _____ homeostasis in circulation

Answer 16

Ca2+

Question 17

______ provides the majority of the circulating 1,25(OH)2D3

Answer 17

kidney

Question 18

the active form of vitamin D is commonly referred to as

Answer 18

calcitrol

Question 19

caries risk _______ w insufficiency of Vitamin D

Answer 19

increases

Question 20

biologically active form of vitamin D

Answer 20

1-alpha, 25(OH)2-D3

Question 21

the skeleton, gut, and kidney play critical roles in the homeostasis of _____

Answer 21

Ca2+

Question 22

serum levels of ______ are an indicator of how much vitamin D is entering the host; _____ is transported in serum by Vitamin D binding protein (DBP) which is a member of the albumin family of proteins

Answer 22

25(OH)D3

Question 23

produced by the chief cells of the parathyroid gland in response to low calcium levels in the circulation. It acts to increase Ca2+ levels. Stimulates production of 1,25(OH)2D3, the biologically active form of Vitamin D.

Answer 23

parathyroid hormone (PT)

Question 24

T/F: VDR does not play a role in hari growth

Answer 24

False

Question 25

parathyroid receptor involved in Ca2+ homeostatsis; binds both PTH and PTHrP

Answer 25

PTH1R

Question 26

encoded by the CASR gene and is a gene coupled receptor

Answer 26

CaSR

Question 27

Vitamin D3 exerts its cellular actions by binding to ________ in target cells

Answer 27

Vitamin D receptor (VDR)

Question 28

regulates the release of parathyroid hormone produced by the parathyroid hormone

Answer 28

CaSR

Question 29

produced by the chief cells of parathryroid gland used to increase Ca2+ levels

Answer 29

parathyroid hormone

Question 30

a transcription factor regulating the expression of genes which mediate its biological activity (member of large family of nuclear hormone receptors). widely distributed among tissues, not just the classic targets of vitamin D. Upon binding 1,25-(OH)2D3, forms a heterodimeric complex with other nuclear hormone receptors, particularly the Retinoid-X-Receptor. Heterodimeric complex binds to DNA promoter sequences containing VDRE or vitamin D response element sequences in genes it regulates. Other proteins called co-activators complex with the activated VDR/RXR heterodimers to recruit the proteins required for transcription such as RNA polymerase II to the transcription start site.

Answer 30

vitamin d nuclear receptor (VDR)