Short note on Ischaemia. [TU 2054]
- Is a state, when a tissue or organ has it’s arterial perfusion lowered relative to its metabolic needs.
- Is simply defined as a condition of inadequate blood supply.
- When ischemia is severe death of tissue results. (necrosis of cells occur)
Short note on Infarction. [TU 2073/7]
Infarction is tissue death (necrosis) due to inadequate blood supply to the affected area. It may be caused by artery blockages, rupture, mechanical compression or vasoconstriction. The resulting lesion is referred to as an infarct.
Types of infarct?
- A. According to color
- - Pale or anemic - Kidney, heart, spleen
- - Red or hemorrhagic - Liver, Lung, Intestine [@ Red LiLI]
- B. According to age
- - Recent or fresh
- - Old or healed
- C. According to presence/absence of infection
- - Bland
- - Septic
What is necrosis?
It is the spectrum of morphological changes that follow cell death in living tissue largely resulting from the progressive degenerative action of enzymes on the lethally injured cell.
- - Coagulative necrosis
- - Liquifactive necrosis
- - Caseous necrosis
- - Fat necrosis
- - Fibrinoid necrosis
Define granulomatous inflammation. List its causes. Define morhphology of tuberculous granuloma. [TU 2063/2]
Short note on Granulomatous inflammation. [TU 2070/5]
- Granulomatous inflammation is a distinctive pattern of chronic inflammatory reaction
- It is a protective response to chronic infection or foreign material, preventing dissemination and restricting inflammation.
- Some autoimmune diseases such as rheumatoid arthritis and Crohns disease are also associated with granulomas.
What is Granuloma?
- Epithelioid cells fuse to form giant cells containing 20 or more nuclei.
- The nuclei arranged either peripherally (Langhans-type giant cell ) or haphazardly (foreign body-type giant cell).
- These giant cells can be found either at the periphery or the center of the granuloma.
What are the types of Granulomatous Inflammation?
2. Foreign Body Granulomas
- 1. Immune granulomas
- Caused by insoluble particles that are capable of inducing a cell- mediated immune response
- Macrophages are transformed into Epitheloid cells and multinucleate giant cells
- a) Bacteria - Tuberculosis,Leprosy
- b) Parasites - Schistosomiasis
- c) Fungi - Histoplasmosis, Blastomycosis
- Don’t incite either an inflammatory or immune response. Epitheloid cells and giant cells are apposed to the surface and encompass the foreign body. The foreign body is usually found in the center of the granuloma. Examples: Metal/Dust Berylliosis Silicosis Foreign body Splinter Suture
3. Sarcoidosis - Bad systemic disease, probably autoimmune disease. Etiologic agent is unknown.
Causes of granulomatous diseases?
- Infectious causes:
- ► Bacteria Tuberculosis Leprosy
- ► Parasites Schistosomiasis
- ► Fungi Histoplasmosis Blastomycosis
- ► Metal/Dust Berylliosis Silicosis
Mechanism of granuloma formation?
- ► Granuloma: bacilli are inhaled by droplets
- ► Bacteria are phagocytosed by alveolar macrophages
- ► After amassing substances that they cannot digest, macrophages lose their motility, accumulate at the site of injury and transform themselves into nodular collections; the Granuloma
- ► A localized inflammatory response recruits more mononuclear cells
- ► The granuloma consists of a kernel of infected macrophages surrounded by foamy macrophages and a ring of lymphocytes and a fibrous cuff (containment phase)
- ► Containment usually fails when the immune status of the patient changes; the granuloma caseates
Define embolus. Describe different types of emboli and their effects. [Tu 2065/12]
Embolus is the detached intravascular solid/liquid/gaseous mass that is carried by blood to distant from its point of origin.
Embollism - Process of partial or complete obstruction of some part of cardiovascular system by emboli.
Describe in brief tumor necrosis factor (TNF). [TU 2064/4]
- TNF-α is chiefly produced by activated macrophages.
- It can be produced by other cells such as CD4+ lymphocytes, NK cells and neurons.
- - Induce tumor cells apoptosis and cachexia (hence the name tumor necrosis factor)
- - Mediate inflammation
- - Protective immune response against the variety of infectious pathogens
- - Being and endogenous pyrogen, it is able to induce fever
- - To inhibit tumorigenesis and viral replication
Describe briefly different types of thrombi. 4 2064/12
- Describe the mechanism of Type I hypersensitivity.
- Factors that influence tissue repair
- Short note on Septic Shock. [TU 2070,72]
- Define anaerobiosis. How do you send a pus sample to the lab for anerobic culture? 2070/12
- Describe morphology of arterial and venous thrombi 2068/5
- Chemical mediators of inflammation
- Describe briefly pathogenesis of HIV infection 2066/1
- List important hypercoaguable states. Describe briefly different types of thrombi 2064/12
- Describe different steps in wound healing by secondary intention. 4 2064/5
- List local and systemic factors that retard wound healing 2063/12
- Pathogensis of acute inflammation 2060/12
- c. Shock 2056
- d. Chemical mediators 2056
- Phagocytosis 2054
- Chemical mediators 2054