Skip to main content

Don't struggle financially

Don't struggle financially
Start investing your small change today

Progressive Types Of Cell Injury & Response

Progressive Types Of Cell Injury & Response

Investigating disease includes collating a clinical history, examination, offering a provisional diagnosis and providing a confirmation of diagnosis via diagnostic or lab investigation.





Cell injury can be caused by:

  • Physical trauma
  • Extreme temperatures 
  • Electrical disturbance  
  • Chemical or radiation poisoning 
  • Biological agents
  • Nutritional issues
Most of the above cause radical production, a decrease in oxygen delivery or an increase in calcium intercellular release. They could be either reversible or irreversible causing necrosis (cell/ tissue injury) or apoptosis (normal physiological process).

Hypoxia conditions can include:

  • Stroke
  • Brain trauma
  • Arteriosclerosis 
  • Injury leading to hypoxia
  • A decrease in ATP production 
  • An increase in sodium and H2O into cells
  • An increase in potassium outside the cell
  • Increased osmotic pressure
  • Vacuoles formed
  • Increased vaculation
  • Increased hydropic degradation 

Progressive types of cell injury and response 

Cellular adaptation - atrophy, hypertrophy, hyperplasia and metaplasia
Active cell injury - immediate response of the cell
Reversible - decreased ATP, oedema, detachment of ribosomes, autophagy of lysosomes
Irreversible- severe vasculation, Calcium moved into the cell, mitochondrial damage
Apoptosis - normal pathological programmed cell death
Chronic cell injury- subcellular alterations
Accumulations - H2O, pigments, lipids, glycogen and proteins
Pathological calcification- dystrophic and metastatic calcification 
Inflammation - a reaction of vascularized tissue to local injury
Non-specific - a defence response of the body, response to tissue damage 
1st line of defence - skin, epithelial cells of the GI tract
2nd line of defence - inflammation 




Types of necrosis

Necrosis involves oedema and breakdown of organelles including tissue damage via lysosomal enzymes
Coagulative necrosis - tissue appears swollen and firm, no autolysis
Liquefaction necrosis - neurons rich in hydrologic enzymes 
Casseous necrosis - tuberculosis and granulomas

Vascular defence sequence 

  1. Immediately there are pattern recognition receptors 
  2. Mast cells
  3. Granulocytes (neutrophils, eosinophils, basophils)
  4. Monocytes/ macrophages 
  5. NK cells
  6. Platelets 
  7. Endothelial cells
  8. No memory involved
  9. Peptides (complement, clotting factors and kinins)
  10. Four physical symptoms (redness and heat due to hyperaemia, increased blood flow, pain due to chemicals (bradykinin),  nerve pressure and damage and swelling due to increased capillary permeability and filtration

3 basic stages of inflammation


  1. Vascular response, 
  2. Emigration of phagocytes from blood to interstitial fluid & 
  3. Tissue repair 

Vascular Response 

  • Changes that occur in the region of tissue injury include:
  • Blood vessel dilation
  • Increased permeability in capillaries 
  • Increased blood flow to remove toxin and dead cells
  • Adherence of white blood cells to inner walls of blood vessels
  • Immediate
  • Swelling
  • Plasma moves out and blood flow slows as blood increases in viscosity
  • Increased blood flow and RBC count leading to redness
  • WBC adhere to capillary walls, biochemical mediators e.g histamine stimulates endothelial cells to retract and more plasma enters leading to swelling.

What substances are involved?

  • Histamine (basophils, platelets and mast cells)
  • Neutrophils attracted to injured site stimulates release of histamine kinins
  • Prostaglandins (lipids are released from damaged cells)
  • Leukotrienes
  • Result in vasodilation and increased 

Labels:

Comments

Post a Comment

Start Investing Your Loose Change

Popular posts from this blog

Vascular & Cellular Changes Produced By Chemical Mediators Causing Inflammation

Vascular & Cellular Changes Produced By Chemical Mediators Causing Inflammation Inflammation is a vascularised response to injury, mostly an immune response to infectious organisms, trauma, surgery, chemicals and extreme heat and cold. The suffix "itis" e.g. appendicitis characterises inflammation, therefore appendicitis is inflammation of the appendix.   Acute inflammation Symptoms Includes vascular and cellular phases including: Redness due to hyperemia (increased blood flow) Heat due to hyperemia Swelling due to increased capillary permeability and filtration Pain due to inflammatory chemicals (bradykinin) and fluid pressure on nerves or nerve injury. The purpose of inflammation is to decrease the spread of pathogens giving the body an increased chance of removing them and damaged tissue debris and to repair the tissue damage.  The sequence of acute inflammation Change in vascular calibre and blood flow Change in vascular blood flow Cellul...
Post a Comment
Read more

Vascular Cellular Repair and inflammation response

Sequence Of Events for Vascular Cellular Repair and the Inflammation Response A break in the skin occurs Bacterial reproduction increases Macrophages engulf bacteria Macrophages secrete cytokines Activated mast cells secrete histamine Histamine and cytokines increase dilation of blood vessels White blood cells (WBCs) adhere to capillary lining (pavementing) WBCs migrate to injured site via endothelial cellular gaps via diapedis movement Monocytes turn into macrophages Macrophages and neutrophils engulf pathogens (phagocytosis) Red Blood Cells increase in concentration causing redness and head An increased amount of fluid migrates to the area causing swelling and pain. Tissue repair commences and systemic responses may be evident e.g. fever What is involved in the tissue repair response? Resolution – the toxin is neutralized, oedema decreases, capillary permeability decreases and vasoconstriction occurs Regeneration & replacement – proliferation...
Post a Comment
Read more

Discipline of Toxicology and Specialty Fields

Many of the different professional groups may be involved in dealing with toxic chemicals including chemists, environmental scientists, food scientists, forensic scientists, clinical scientists, and regulators. Depending on their professional roles, they may take different approaches to dealing with toxic chemicals and their effects.  5 Types of Toxicology Specialty Fields Descriptive toxicology Involves toxicity testing of drugs and chemicals. Decides if a substance is toxic and the level of toxicity. Mechanistic toxicology Involves how toxic chemicals cause toxicity effects at the biochemical and system level e.g. neurochemical site blockage Regulatory toxicology Assessment of therapeutic and consumer chemicals by regulatory bodies. Various federal government agencies set standards for use, transport, and storage.  Clinical toxicology Clinical Toxicologists ask the question, what was the victim poisoned with? Their conduct is in support of medi...
Post a Comment
Read more