2. +
Introduction
Manifestations of metabolic derangements in cells
Accumulation of abnormal amounts of various substances
Located in cytoplasm , organelles , nucleus
Synthesized by the cells or produced elsewhere
7. +
TYPES OF PIGMENTS
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• They are coloured substances varying in chemical composition
• ENDOGENOUS (Manufactured by special cells of the body)
• EXOGENOUS (absorbed from outside).
12. +
USES OF DOPA REACTION
Incubate melanocytes with tyrosine or DOPA gives rise to melanin
production
Helps diagnose amelanotic melanoma.
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13. + Factors affecting melanin distribution
Site
no of melanocytes in palmar epidermis < dorsum
Racial
↑activity of melanocytes (not much ↑in no )in dark skinned
people
Hormonal control
Pituitary: secretes ACTH which has MSH like activity →may
result in dark skin.
Adrenal gland: inhibits MSH activity
Sex hormones:
Estrogens causes ↑pigmentation
Pregnancy
OC pills
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22. Catabolism of Haem
Haemoglobin →Haem + Globin
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Fe containing fragment.
Goes to Fe stores mainly
as Haemosiderin
Non Fe containing
Haematoidin
Biliverdin
Bilirubin(carried to liver by albumin)
Conjugated by glucuronyl
transferase with glucronic
acid
Dissociates from albumin
Conjugated bilirubin
To protein stores
Urobilinogen in intestine
Carried back to liver
Exc in urine
Exc as stercobilin
23. + Storage iron
60% in Hb
5% in Myoglobin
0.25% in cells (cytochrome,catalase)
Rest in stores (ferritin and haemosiderin)
Ferrous state {FERRITIN}
16% Fe
Combined with βglobulin (apoferritin)
P.B negative
Ferric state {HAEMOSIDERIN}
24-45% Fe
no protein
PB positive.
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24. +
Prussian blue reaction
Section washed free from blood
Dipped in 2% solution of K ferrocyanide
Then in 1% HCl
+ ve test – Blue color
Reaction:-
Ferric iron + 2% K ferrocyanide + 1% HCl → ferric ferrocyanide
(blue).
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25. + Abnormalities with haemosiderin deposition
- Localized
Hemorrhage – breakdown of RBCs – haemosiderin in
macrophages.
Eg. organizing haematoma, fractures, sclerosing
haemangioma
Renal tubules – Hb uria – breakdown of Hb to
haemosiderin – stored in renal tubules
Pulmonary:
Small hemorrhage
occur in lung after MS or LVF
Heart failure cells – haemosiderin in al macrophages
Brown induration – followed by fibrosis in long standing cases
Idiopathic in children and young adults
Pulmonary haemosiderosis associated with AGN - Good
pastures syndrome.
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28. +Abnormalities with haemosiderin
deposition – Generalized
When the body is Fe over loaded
↑Fe in diet (Bantu)
Chronic haemolytic anemia
Haemochromatosis (↑Fe abs)
Parental Fe administration
Repeated blood transfusion
Parenchymatous
Liver, pancreas, kidney, heart
Reticulo-endothelial
Liver, spleen, BM.
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29. +
Haemochromatosis (bronze DM)
AD
Alteration in regulation of Fe absorbtion
More in males, females protected by menstrual loss
Seen (parenchymatous distribution)
Liver cells – cirrhosis
Pancreas – DM
Skin – Bronze skin (melanin + lipofuschin deposits in sweat glands)
Joints – polyarthritis (small joints of hands, wrists, elbow,hips knee, ankle).
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30. +
Bilirubin
Unconjugated
Insoluble (held in sol by albumin)
Indirect Van den bergs +ve
Not excreted in urine
Conjugated
Water soluble
Direct Van den bergs +ve
Excreted in urine if ↑
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32. +
Changes in the organ
Body tissues + fluids – stained yellow
Liver – greenish
Eyes – yellow
Micro:
Bile pigment in hepatocytes, kupffer cells, canaliculi
Fibrosis in later stages
Bile staining of basal ganglia – kernicterus, in children due to poorly
developed BBB.
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33. 33
The yellow-green globular material seen in small bile ductules in
the liver here is bilirubin pigment. This is hepatic cholestasis.
34. +
Porphyrins
Metabolic bi-products which has escaped from the path of
biosynthesis to haem
Genetic/ acquired
Deposited in teeth, bones & other tissues
Urine – bright red .
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37. + Lipofuschins
Peroxidation of unsaturated lipids
Endogenous brown granules
Called as wear and tear pigments:
myocardial fibers
liver cells
epithelial cells
seminal vesicles and prostate
nerve cells
Brown atrophy of heart and liver
seen in old age, malnutrition, wasting …..
Intestinal lipofuschinosis (malanosis coli)
Vit E def, mal-absorption.
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