What are the systemic effects of inflammation?

Inflammation, even if it is localized, is associated with cytokine-induced systemic reactions that are collectively called the acute-phase response.

1. Fever: Cytokines (TNF, IL-1) stimulate production of PGs in hypothalamus.

2. Production of acute-phase proteins: C-reactive protein & others; synthesis stimulated by cytokines (IL-6 & others) acting on liver cells.

3. Leukocytosis: Cytokines (CSFs) stimulate production of leukocytes from precursors in the bone marrow.

4. In some severe infections, septic shock: Fall in blood pressure, disseminated intravascular coagulation, metabolic abnormalities; induced by high levels of TNF and other cytokines.

How free radicals are initiated? What are their effects on cells?

How free radicals are produced:

Free radicals are chemicals species that have a single unpaired electron in an outer orbit. Unpaired electrons are highly reactive and attack and modify adjacent molecules, such as inorganic or organic chemiclas proteins, lipids, carbohydrate, nucleic acids many of which are key components of cell membranes and nuclei.

Free radicals may be generated within cells in severals ways:
1. The reduction oxidation reactions that occur during normal metabolic processes.
2. Absorption of radiant ebergy(e.g. ultraviolet light, x-rays)
3. Rapid bursts of free radicals are produced in activated leukocytes during inflammation.
4. Enzymatic metabolism of exogenous chemicals or drugs can generate free radicals that are not reactive oxygen specices but have similar effects.
5. Transition metals such as iron and copper donate or accept free electrons during intracellular reactions and catalyze free radical formation.
6. Nitric oxide an important chemical mediator generated by endothelial cells, macrophages, neurons and other cell types.

Effects of free radicals:
1. Lipid peroxidation in membranes.
2.Oxidative modification of proteins
3. Lesions in DNA

What are the defficiency effects of Vit-D?

Deficiency effects of Vit-D:

• Rickets in children
• Osteomalacia in adults

What are the effects of Vit-A defficiency?

Deficiency effects of Vit-A:

• Night blindness
• Xerophthalmia
• Blindness
• Squamous metaplasia
• Vulnerability to infection, Particularly measles.

Describe the effects of cellmembrane damage.

Plasma membrane damage results in loss of osmotic balance and influx of fluids and ions as well as loss of proteins, enzymes, co-enzymes and ribonucleic acids. The cells may also leak metabolites, which are vital for the reconstitution of ATP thus further depleting net intracellular high energy phosphates. Injury to lysosomal membranes results in leakage of their enzymes into the cytoplasm and activation of these enzymes. Activation of these enzyme leads to enzymatic digestion of cell components resulting in loss of ribonucleoprotein, deoxyribonucleoprotein and glycogen and the cells die by necrosis.