General Pathology

·         INFLAMMATORY RESPONSE:

o   1^st 24 hours = Swelling

o   In 24 hours → neutrophils → peak at Day 3

o   Day 4 → T-cells/MФ → peakat Day 7

o   Day 7 → Fibroblasts → peak at Day 30

§  Takes 6 mos. to finish scarring

o   If Acute = look for neutrophils

o   If Chronic = look for fibrosis/sclerosis

·         Noncaseating Granulomas: SARC FOR FUN

 Sarcoidosis

foreign-body reaction

fungal infections

·         Fibrillar Collagens

type I → skin, bones, tendons, mature scars

type II → cartilage

 type III → embryonic tissue, blood vessels, pliable organs, immature scars

Amorphous Collagens

 type IV → basement membranes

 type VI → connective tissue

·         The fibrillar (interstitial) types of collagen (types I, III, and V) are found within the ECM (interstitial tissue), while the nonfibrillar type IVcollagen is found within the basement membranes,

·         G proteins may be classified into four categories, namely Gs, Gi, Gt, and Gq.

Gs and Gi, regulate the intracellular concentration of cyclic adenosine 5'-monophosphate (cAMP). Gs and Gi regulate intracellular cAMP levels by their actions on adenyl cyclase, an enzyme located on the inner surface of the plasma membrane that catalyzes the formation of cAMP from ATP.

Gt regulates the intracytoplasmic levels of cyclic guanosine 5'-monophosphate (cGMP), and

Gq regulates the intracytoplasmic levels of calcium ions.

ADP-ribosylates G_s = Turn the On, On

• VibriO
• ETEC (E.cOli)

ADP-ribosylates G_i = Turns the Off, Off

• Bordetella pertussis

Ribosylation of EF₂

• Pseudomonas
• Diptheria

In pseudohypoparathyroidism, the activities of the G proteins are reduced and as a result there is a reduced response to parathyroid hormone, T3 and gonadotrophins.

·         Beta-naphthylamine is an exception to the general rule involving cytochrome P450, as the hydrolysis of the nontoxic conjugate occurs in the urinary bladder by the urinary enzyme glucuronidase. There has been an increase in bladder cancer in workers in the aniline dye and rubber industries who have been exposed to these compounds.

·         Amniotic fluid emboli can also lead to DIC which results from the high thromboplastin activity of amniotic fluid.

·         anlage → primitive mass of cells

aplasia → complete failure of an organ to develop (anlage present)

·         Staining reaction of amyloid material

ü  Iodine gives brown- colour and I2 followed by H2S04 gives blue colour Congo red  -red

ü  Methyl violet—rose red while other tissue becomes blue (metachromatic stain).

ü  Von-Gieson’s stain—Khaki shade

ü  PAS stain—red.

ü  Iodide green—(metachromatic stain)—violet red other stained green.

ü  H- & E stain—faintly eosinstained homogenous material.

ü  Fluorescent dyes—to demonstrate amyloid in juxta glomerular area of kidney.

ü  Immunohistological stain—to distinguish between AL and AA.

·         In Fenton reaction, Hydroxyl Radicals are generated by interaction of Hydrogen peroxide with Transitional metals like Iron, Copper.

·         The major antioxidant enzymes are — Superoxide dismutase, catalase, Glutathione peroxidase.

·         Fatty change is due to:-

 In alcohol poisoning — Increased esterification of fatty acids to Triglycerides.

In carbon tetrachioride, phosphorous poisoning and protein malnutrition —Decreased Apoprotein synthesis.

In experimental Fatty liver induced by orotic acid — Impaired secretion of lipoprolein.

Starvation, corticosteroids — Excessive entry of free fatty acids into the liver.