Manar Hajeer, , MD, FRCPath th Unive vers rsity ity of Jordan - PowerPoint PPT Presentation

Manar Hajeer, , MD, FRCPath th Unive vers rsity ity of Jordan an , school ol of medicine cine

Cells Tissues Organs Systems Organism

 Physiologic adaptation  Pathologic adaptation.

➢ Many forms: ➢ Increase in cell size. ➢ Increase in number of cells. ➢ Change into another type of cell  Adaptation to stress can progress to cell injury if the stress is not relieved.

• Inc ncreased eased size e & & fu funct nctio iona nal l capacit pacity • Pure e or mixed xed • Inc ncreased eased struc uctural tural protein teins and d organe anelles. lles. • Pathologic hologic vs vs physio siolo logic gic • Due e to • hormon ormonal al stimu mulat latio ion • Growth owth fa factor ctor sti timu mula latio tion • inc ncreased eased function nctional l deman mand

• Increase in number of • Path tholo logi gic c hyperplas perplasia ia cells • excessive hormonal stimulation • Tissues that have • Viral Infections proliferative ability • Pure vs Mixed  Pathologic hyperplasia • Physiologic vs constitutes a fertile soil in Pathologic vs cancer which cancers may eventually arise. • Physiolo iologic gic hyper erpla plasia ia: • hormonal stimulation • Compensatory

 Physio siolog ogic ic  Breast in puberty and pregnancy  Liver after partial resection  Pa Pathol hologi gic  Endometrial hyperplasia, estrogen induced.  Benign prostatic hyperplasia, androgen induced.  Warts (HPV).

➢ Decreased cell size & function ➢ Mechanism: ↓ Protein synth ↑ Degradation ↑ Autophagy ➢ Atrophic cells can still function

 Decreased workload (immobilization of a limb after fracture)  Loss of innervations  Diminished blood supply,  Inadequate nutrition  Loss of endocrine stimulation  Aging (senile atrophy)

 Ph Phys ysio iologi ogic  Loss of hormone stimulation in menopause (endometrial atrophy)  Pathol hologi gic  Denervation injury.  Chronic ischemia.

➢ Change from one cell type to another ➢ Reprogramming of stem cells NOT differentiated cells ➢ Persistent change increases risk of cancer ➢ New cell type copes better with stress but function less. ➢ Reversible ➢ Causes: Smoking , Vitamin A deficiency, GERD.

➢ Oxygen Deprivation (Hypoxia Vs ischemia) ➢ Chemical Agents ➢ Infectious Agents ➢ Immunologic Reactions ➢ Genetic Factors ➢ Nutritional Imbalances ➢ Physical Agents ➢ Aging