Ancylostoma
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A stenotic valve is removed from an 70 year old man. The value demonstrates hard nodular masses heaped up within the sinuses of vasalva. On microscopic sections acellular masses stain dark blue with eosin. Which of the following is most significan constituent of the masses ?
A Calicum Phophates
B Calcium Oxalates
C Complexed Iron
D Magnesium phophates
E Uric acid
Dont forget explanation
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| MRMAVERICK
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i know the answer as i read it somewhere but will nt be able to explain it appropriately so let someone else try
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| me007
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dystrophic calcification?
A
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| po
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Hematoxylin stains nucleic acids, bacteria, and calcium blue. Eosin stains arginine and lysine (i.e., protein molecules) pink. PAS stains insoluble carbohydrates magenta; d-PAS stain is used to prove something PAS-positive is, or is not, glycogen.
Acid-fast stains selectively stain mycobacteria.
Fatty change is too much fat in business cells which shouldn't ordinarily accumulate it; it's a sign that the cell is sick. Fatty ingrowth is extra fat cells in an organ where they don't usually belong.
Hemosiderin is iron storage pigment. You distinguish it using the Prussian Blue stain.
Melanin is the familiar skin pigment. You distinguish it because it loses its color on being exposed to hair bleach.
Bilirubin pigment generally occurs with bile plugs or bile lakes in the liver.
Lipofuscin is an inert, wear-and-tear pigment. You distinguish it by its location, or by process of elimination.
Dystrophic calcification results from disease at the site of calcification. Metastatic calcification results from disease remote from the site of calcification that has caused elevated blood calcium or phosphate.
"Hyaline" is a generic term for amorphous masses protein (usually a single protein).
Amyloid is beta-pleated anything. You identify it using Congo Red staining.
Hematoxylin and eosin (H&E) is the standard tissue stain.
The pedagogical explanation ("hematoxylin is basic and stains acids, eosin is acidic and stains bases") isn't exactly so.
Hematoxylin (blue-purple) is a metal chelator. We usually use it with aluminum ions, which link it to fixed phosphate groups. Hematoxylin stains nucleic acids, calcium salts, and bacteria blue-purple. (* Hematoxylin comes from an exotic jungle tree.)
Eosin (red) binds to free amino groups and thus stains arginine and lysine pink. (* Eosin, which is fluorescent, is a major component of many colors of lipstick. It's also the red dye on pistachio nuts.)
Air, water, fat, and carbohydrate end up unstained.
The Romanowsky stain family, including Wright and Giemsa, use a similar color scheme, though with somewhat different dyes and some nice metachromasia. You'll encounter these stains when we study blood and bone-marrow smears.
Periodic acid-Schiff (PAS) is a stain based on the familiar * periodic acid (H+IO4-) oxidation (cis-diols to aldehydes) and * Schiff-base reactions.
Anything with a cis-dihydroxy group, i.e., insoluble sugar compounds such as ...
+ glycogen;
+ epithelial mucin;
+ cartilage;
+ fungus wall;
+ basement membranes;
+ reticulin;
+ alpha-1 protease inhibitor (antitrypsin);
+ type I collagen (weak);
+ all amyloids (weak);
... gets stained magenta.
Diastase-PAS ("d-PAS") is the PAS reaction performed on tissue previously digested by diastase, which removes glycogen.
The pathologist can buy diastase, or can spit on the slide before staining. If something is PAS-positive and d-PAS negative, you know it is glycogen.
Reticulin stains the delicate fibers that surround small blood vessels and hold together liver, spleen, and lymph nodes.
* Today's pathologists are more likely to use an immunoperoxidase stain.
Prussian Blue uses a special solution of * ferrocyanide.
By the familiar reaction (college chemistry, laundry bluing, old-fashioned blueprints), it stains all exposed ferric ions very blue.
Congo Red is a special dye that fits tightly into beta-pleated proteins of all sorts.
Beta-pleated proteins in humans are abnormal and are called amyloids. Congo Red stains all amyloids brick red, and everything else pink. Because of the way beta-pleated sheets line up Congo Red, amyloids also acquire an apple green birefringence when stained with Congo Red and then examined under polarized light.
Sudan / Oil Red O are oil-based stains that can only be used on thin slices ("frozen sections") of tissue from which fat has not been removed. (* Future pathologists: Phospholipids are pink).
These stain only fat (usually black or bright red). The principle is of course hydrophobic bonding.
Mucicarmine is a special dye that stains only epithelial mucin (usually red). The actual chemistry remains mysterious.
* Alcian blue stains certain mucoid substances (hyaluronic acid, sulfomucin, maybe carboxymucin depending on the recipe).
Trichrome uses familiar aniline dyes to stain collagen (type I, also basement membranes) blue or green and everything else some other color. The stain depends on the special way collagen is woven.
Acid-fast stains (ZN, auramine O, others) stain certain waxes a permanent red (or some other color). This shows up mycobacteria (TB bugs) and certain other rare substances.
Argentaffin stains test the ability of cell structures to bind and reduce silver, while argyrophil stains demonstrate all sites of silver binding, whether or not reduction occurs. (Everything that is argentaffin is argyrophil, but not vice-versa.)
Methenamine silver is the most sensitive and specific common stain for fungi and pneumocystis. It stains them black.
Elastic stains (Verhoeff, Van Gieson) selectively stain elastic fibers (typically black).
Metachromatic stains take advantage of molecule-stacking. A single dye will impart a variety of hues to different structures. The most important metachromatic dyes are those use to stain blood and bone marrow smears (the various azures); * Bismark brown imparts a metachromatic yellow on pap smears.
* Light green stains RNA green.
* Orange G stains disulfide bonds orange.
* Papanicolaou's stain is used for cytology (i.e., smears of cells on glass slides, "Pap" smears). It contains hematoxylin, eosin, light green, orange G, and sometimes Bismark brown.
* Methyl green pyronine stains RNA red and everything else green.
Immunostaining (immunofluorescence, immunoperoxidase) uses monoclonal antibodies to demonstrate specific antigens (i.e., specific proteins) in tissues.
* Immunostaining, and studying how antigens can be lost and recovered, has clarified the mechanism of formalin fixation. Recoverable antigens involve cross-linking of a tyrosine and an amino-sidechain (usually arginine). Am. J. Clin. Path. 121: 190, 2004.
Nucleic acid probes are now being introduced to stain particular genes and their RNA's. For example, a cancer cell that contains mRNA for albumin must be of hepatocyte origin.
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| po
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Hematoxylin (blue-purple) is a metal chelator. We usually use it with aluminum ions, which link it to fixed phosphate groups. Hematoxylin stains nucleic acids, calcium salts, and bacteria blue-purple.
me007 must be right.
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| po
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since they usually use H&E STAIN
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| Luckyall
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Wow, long explanations... , i read it somewhere, either Q bank or Robbins Review of Patho Qs book... i guess distrophic Calcific..... just a guess
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| Ancylostoma
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A The answer is dystrophic calcification, you can read the really long explanaition or know that kaplan asks you to memorize 4 important things that come up purple on HE DNA, RNA, Calcium, Bacteria. I think its the first chapter of the path book. Anyway after that you then know that your dealing with congenital calcific aortic stenosis, the most common valvular defect, MC cause of syncope w exercise, and one more MC I forgot(sorry). It is caused by old age that lead to damage over time to the valve and dystrophic calcification. You guys probably knew this, just clarifying.
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| po
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q said stains blue with eosin,shud have been h&e both,so wanted to study path stains;ie why long explanation.
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