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Pheochromocytoma: It is a tumour of the adrenal medulla ( or sympathetic ganglia ) that secretes excess catecholamines ( that is epinephrine and norepinephrine) Adrenal gland has two main layers, cortex and medulla, the cortex is further subdivided into 3 zones and every zone secretes a specific set of hormones. The adrenal medulla secretes epinephrine and norepinephrine. In normal conditions, adrenal medulla secretes catecholamines after the stimulation of the sympathetic nervous system. Hence sympathetic overactivity or adrenal medulla tumour will result in increased secretion of catecholamines. These excessive catecholamines result in symptoms of pheochromocytoma.

Define The Terms: 1) Argyle Robertson Pupil:     It is a pupil that: a) remain constricted b) Doesn't respond to accommodation. Cause : The lesion in the vicinity of the aqueduct of Sylvius and superior colliculi in syphilis of CNS. 2) Horner's Syndrome: It is the collection of symptoms resulting from interruption of sympathetic nerve supply to eyes. Symptoms are; a) Miosis, that is pupil remain constricted. b) Ptosis, that is superior eyelid drops, c) Anhidrosis, that is sweating on the affected side does not occur. d) Vasodilation of blood vessels of the affected side. 3) Xerophthalmia: It is a disease characterized by small triangular white patches on outer and inner sides of cornea. Caused by: Vitamin A deficiency. 4. Keratomalacia: It is a disease in which cornea becomes dull, insensitive and necrotic. Caused by: Severe Vitamin A deficiency. 5. Anisocoria: If two pupils are unequal, this is called anisocoria.

Following disorders predispose to Cor pulmonale or right heart failure. 1. The disease of the pulmonary parenchyma. a) Chronic Obstructive Pulmonary Disease b) Diffuse Pulmonary interstitial fibrosis c) Pneumoconiosis d) Cystic Fibrosis e) Bronchiectasis 2. Disease Of pulmonary vessels. a) Recurrent pulmonary thromboembolism b) Primary Pulmonary Hypertension c) Extensive pulmonary arteritis (eg, in Wegener's granulomatosis) e) Drug, toxin or radiation-induced vascular obstruction f) Extensive pulmonary tumour and micro- embolism 3. Disorders Affecting Chest Movements. a) Kyphoscoliosis b) Marked Obesity (eg, Pickwickian Syndrome) c) Neuromuscular disease 4. Others: a) Metabolic acidosis b) Hypoxemia c) Chronic altitude sickness e) Idiopathic alveolar hypo-ventilation.

Hypothyroidism : Hypothyroidism means " Insufficient secretion of thyroid hormones ( T3 and T4 ) by the thyroid gland. Causes Of hypothyroidism: 1. Thyroid Parenchymal defects: a) A congenital defect in thyroid parenchyma b) Radiation injury to thyroid parenchyma (e.g radio-iodine, external radiation) c) Surgical ablation d) Hashimoto's thyroiditis. 2. Interference with Thyroid hormone synthesis: a) idiopathic primary hypothyroidism (possibly due to immune blockade of TSH receptors) b) Heritable biosynthetic defects c) Iodine deficiency. d) Drugs (e.g iodides, p-aminosalicylic acid, lithium etc) e) Hashimoto Thyroiditis 3. Others: a) Pituitary lesions reducing TSH secretion b) Hypothalamic lesions that reduce thyrotropin-releasing hormone (TRH) secretion. TRH stimulates the pituitary to secrete TSH. Types Of Hypothyroidism: There are three types of hypothyroidism. 1. Primary Hypothyroidism: In primary hypothyroidism, problems lie in the thyroid ...

Spirometry:      It is a process of recording volume movements of air into and out of the lungs. Spirogram: Graphical recording of changes in the lung volume under different              Stages of breathing is called spirogram. Pulmonary Volumes: Tidal Volume: It is the volume of air inspired or expired with each normal breath. its value is 500 ml it means 500 ml of air is inspired in each inspiration and 500 ml of air is expired in each expiration. Inspiratory Reserve Volume: IT is the extra volume of air that can be inspired forcefully over and beyond normal tidal volume. its value is 3000 ml. it means 3000 ml of air can be inspired forcefully beyond tidal volume. Expiratory Reserve Volume. It is the extra volume of air that can be expired forcefully over and beyond the normal tidal volume. Its value is 1100 ml. it means 1100 ml of air other than tidal volume can be expired forcefully. Residual Volume...

Triple Sugar Iron Medium (TSI medium) This medium is prepared in a test tube, the upper portion is called slant and the lower portion is called butt. Composition: 1. Glucose, 2. Sucrose 3. Lactose 4. Ferrous sulphate 5. Tissue extracts (proteins) 6. Phenol red (indicator) Container: Test tube. Colour: Red before reaction (alkaline) yellow after reaction (acidic) Black after hydrogen sulphide gas production due to the formation of FeS. Consistency : Solid medium Uses: This medium is used to differentiate Salmonella and Shigella from other enteric gram-negative rods in stool culture. Micro-organisms/bacteria are cultured. Salmonella and shigella produce:  a). Alkaline slant (red) b). Acidic but with no gas (yellow without bubbles) c) salmonella produces hydrogen sulphide gas but Shigella don't. Other enteric Gram-negative rods produce: a. Acidic slant (yellow) b. Acidic butt with gas ( yellow with bubbles) e.g E. coli Table: Reactions shown by vari...

MacConkey's Medium: Composition: 1. Nutrient agar 2. Bile salt (sodium taurocholate) 3. Lactose 4. Neutral red (indicator) Container : Petri dish Colour : Transparent, reddish-brown or pink colour Consistency: Solid medium. Micro-organism cultured? It is used for: 1. growth and isolation of bacteria of family Enterobacteriaceae and to differentiate between lactose fermenters, non-lactose fermenters and late lactose fermenters. Lactose Fermenters: form pink colonies, for example; E. coli, Klebsiella species, Enterobacter species Non-lactose fermenters: from colorless colonies, for example, shigella species except shigella sonnie, salmonella species, proteus species and pseudomanas species. Late lactose fermenters: form pink colonies after 2-3 days of inoculation. for example, Vibrio cholera, Serratia, Citrobacter, Shigella sonnei. Important Culture Media: a) Nutrient agar b) Blood agar c)Chocolate agar d)McConkey's Medium e) Lowenstein Jensen (LJ) m...

Blood Agar: Composition: 1. Sterile defibrinated blood 5-10 % 2. Melted agar 3. Beef extract 4. Peptone water 5. NaCl container: Petri dish Colour: Opaque red. Consistency: Solid medium. Micro-organism Cultured. This media is used to determine the haemolytic properties of bacteria. 1. Complete (beta) hemolytic bacteria :- Streptococcus pyogenes, 2. Incomplete (alpha) hemolytic bacteria: - Streptococcus viridans, Streptococcus pneumoniae 3. No (gamma) hemolysis:- Staphylococcus Albus, staphylococcus citrus, Staphylococcus epidermidis, etc. Important Culture Media: a) Nutrient agar b) Blood agar c)Chocolate agar d)McConkey's Medium e) Lowenstein Jensen (LJ) medium f) Loeffler's Coagulated Medium g) Robertson's cooked meat medium ) Tripple sugar iron (TSI) medium i) Christensen's Urea Medium j) Simmon Citrate Medium k) Peptone Water l) Nutrient Broth m) Sugar Media

Chocolate Agar: Composition: its composition is the same as blood agar . that is 1. sterile defibrinated blood 5-10 % 2. Melted agar 3. Beef extract, 4. Peptone water 5. NaCl A blood agar plate is put in boiling water for about 1 hour until its colour changes from red to chocolate brown. Heating converts Haemoglobin into hematin. Container: petri dish. Colour : Opaque Chocolate colour Consistency: solid medium Micro-organism Cultured. 1. Haemophilus influenzae 2. Neisseria gonorrheae 3. Neisseria meningitidis 4. streptococcus pneumoniae. Important Culture Media: a) Nutrient agar b) Blood agar c)Chocolate agar d)McConkey's Medium e) Lowenstein Jensen (LJ) medium f) Loeffler's Coagulated Medium g) Robertson's cooked meat medium h) Triple sugar iron (TSI) medium i) Christensen's Urea Medium j) Simmon Citrate Medium k) Peptone Water l) Nutrient Broth m) Sugar Media.

Loeffler's Coagulated Medium: Composition: 1. Ox, sheep or horse serum 2. 1% glucose broth Container: Test tube. Colour: milky white Consistency: Solid medium Micro-organism/bacteria cultured: Corynebacterium diphtheria Important Culture Media: a) Nutrient agar b) Blood agar c)Chocolate agar d)McConkey's Medium e) Lowenstein Jensen (LJ) medium f) Loeffler's Coagulated Medium g) Robertson's cooked meat medium h) Triple sugar iron (TSI) medium i) Christensen's Urea Medium j) Simmon Citrate Medium k) Peptone Water l) Nutrient Broth m) Sugar Media.

Christensen's Urea Medium: Composition 1. Monopotassium phosphate 2. Agar 3. Phenol red 4. Peptone Water 5. NaCl. Container: Test tube Colour: Pink before reaction. red after urea-splitting in urease positive organisms. Consistency. Liquid Medium Uses and bacteria cultured. To demonstrate urease activity by Proteus species Morganella morganii and Helicobacter pylori. Important Culture Media: a) Nutrient agar b) Blood agar c)Chocolate agar d)McConkey's Medium e) Lowenstein Jensen (LJ) medium f) Loeffler's Coagulated Medium g) Robertson's cooked meat medium h) Triple sugar iron (TSI) medium i) Christensen's Urea Medium j) Simmon Citrate Medium k) Peptone Water l) Nutrient Broth m) Sugar Media.

Simmon Citrate Midium: Composition: 1. Mineral Salt solution (bactor agar) 2. Bactro-bron thymol blue (indicator) Container : Test tube. Colour: 1. Green before reaction 2. Blue after reaction Consistency: Liquid medium Bacteria cultured: It is used to demonstrate citrate utilization by; Klebsiella and Proteus species. Important Culture Media: a) Nutrient agar b) Blood agar c)Chocolate agar d)McConkey's Medium e) Lowenstein Jensen (LJ) medium f) Loeffler's Coagulated Medium g) Robertson's cooked meat medium h) Triple sugar iron (TSI) medium i) Christensen's Urea Medium j) Simmon Citrate Medium k) Peptone Water l) Nutrient Broth m) Sugar Media.

Nutrient Broth: Composition 1. Beef extract 2. Peptone water 3. NaCl Container. Test tube Colour Light yellow Consistency  Liquid medium Uses: Used for 1. bacterial growth 2. Coagulase test. Important Culture Media: a) Nutrient agar b) Blood agar c)Chocolate agar d)McConkey's Medium e) Lowenstein Jensen (LJ) medium f) Loeffler's Coagulated Medium g) Robertson's cooked meat medium h) Triple sugar iron (TSI) medium i) Christensen's Urea Medium j) Simmon Citrate Medium k) Peptone Water l) Nutrient Broth m) Sugar Media.

Sugar Media: Composition: 1. Nutrient Broth 2. Peptone water 3. Bromocresol purple (indicator) 4. Sugar (eg. glucose, sucrose, lactose, maltose xylose, mannitol, for which fermentation is to be determined) Container: Test tube. Colour. 1. Purple before reaction 2. Yellow after reaction consistency: Liquid medium Uses: To determine which sugar is utilized by bacteria. Type of sugar contained in a test tube is known by the colour of the cotton plug of the test tube, which are. 1. glucose - green 2. sucrose- white 3. Lactose- red 4. Maltose- Blank 5. Xylose- Blue 6. Mannitol- Violet. Important Culture Media: a) Nutrient agar b) Blood agar c)Chocolate agar d)McConkey's Medium e) Lowenstein jensen (LJ) medium f) Loeffler's Coagulated Medium g) Robertson's cooked meat medium h) Tripple sugar iron (TSI) medium i) Christensen's Urea Medium j) Simmon Citrate Medium k) Peptone Water l) Nutrient Broth m) Sugar Media.

Hydatid Cyst: Hydatid cyst is a fluid-filled cyst present most commonly in the liver. other sites where hydatid cyst may develop include lungs, brain and other organs (where oncosphere settles , discussed here in life cycle ). It contains fluid and from the inner side of the cyst number of brood-capsules develop. With in each brood capsule, thousands of protoscolices are developed. ( to find out what are protoscolices and brood capsule click here ) Cause:

Embolism:             It refers to a condition in which there is complete or partial occlusion of some parts of the cardiovascular system (e.g, arteries or veins) by impaction of some mass (embolus) that has transported to the site through the bloodstream. Emboli : It refers to the mass that occludes the blood vessels and is transported to the site of occlusion through the bloodstream. Classification Of Emboli. (A) Classification According to consistency. 1. Solid Emboli for example part or whole of dislodged thrombus Atherosclerosis debris that is cholesterol emboli. Tumour fragments bits of bone marrow Foreign bodies that gain entry to the bloodstream for example bullet. 2. Liquid Emboli: for example Fat Droplets  Amniotic Fluid 3. Gas Emboli for example Nitrogen bubbles (caisson disease) Air that enters with IV injection. (B) Classification according to the site Of Origin. Venous Emboli: ...

Venous Emboli: Sources Of Venous Emboli; 95 % of venous emboli arise from  thrombi in deep veins of the leg ( that are deep calf, popliteal, femoral and iliac veins) Rarely venous emboli arise from pelvic veins, inferior vena cava or elsewhere. Some special types of venous emboli. 1. Saddle embolus.               It refers to "large snake-like venous embolus that becomes coiled upon itself and impinges on bifurcation of the main pulmonary artery and sits astride the two major subdivisions of the pulmonary artery. such embolus is very dangerous and may cause pulmonary infarction. there is a point to be noted here that lungs also get partial blood supply from bronchial arteries which are branches of aorta hence, complete occlusion of the pulmonary artery is needed to cause pulmonary infarction. 2. Paradoxical Embolus.          It refers to a venous embolus that enters from right side of the heart t...

Fat embolism: It refers to the presence of minute fat globules in the blood circulation. These globules circulate freely in the circulation and block smaller arteries and cause infarction of the organ supplied. Causes of Fat embolism Fracture of shafts of long bones; shafts of long bones contain fatty bone marrow. fracture is also associated with rupture of blood vessels at the injured site, hence some minute fat globule enter in to the circulation through the ruptured blood vessels. Soft tissue trauma Burns Fat embolism syndrome; it occurs in 1 %of individuals following skeletal injuries. Clinical Manifestations: symptoms vary according to the site of emboli lodgment. pulmonary insufficiency, resembling acute respiratory distress syndrome marked by sudden onset of tachypnea, dyspnea and tachycardia Neurological symptoms include irritability, restlessness, delirium or coma Petechial skin rash Anemia. Pathogenesis: Micro-aggregates of neutral fat cause occlusion of pul...