Test Android StudyStack App
Please help StudyStack get a grant! Vote here.
or...
Reset Password Free Sign Up

Free flashcards for serious fun studying. Create your own or use sets shared by other students and teachers.


Decalcification

Quiz yourself by thinking what should be in each of the black spaces below before clicking on it to display the answer.
        Help  

Question
Answer
Removal of calcium salts from bone or calcified tissues   Decalcification  
_____ tissue w/large amounts of calcium results in torn/ragged sections and damage to the cutting edge of microtome   Failure to decalcify  
for routine dx purposes use formalin, use it unbuffered since calcuim phosphate present in the bone serves as an adequate buffer to keep the pH above 6.0,   Fixation  
Nucleic acids are suscpetible to ribonuclease digestion or digestion by mineral acids,if formalin fixation is prolonged more than two days   Nucleic acids  
acid methods (acid, ion exchange, electrolytic method) chelating method   Two Routine decalcification methods  
The stronger the acidity of solution,the longer the specimen remains in it, the more subsequent staining will demonstrate injurious effects of the decalcification. most pronounce effect-nuclear bsophilia   Acid method  
may result in a total lack of nuclear staining   over decalcification  
calcium salts dissolve and then ionize.   principle of acid method  
soluble at a pH of 4.5   calcium salts  
pH between 0.5-3.0   decal solutions  
used in concentration of 5%-10%   simple acids  
decalcify fairly rapidly   hydrochloric and nitric acids  
can cause serious deterioration of tissue beyond 48 hours   Nitric acid  
slower acting, can remain in solution for two weeks   Formic acid  
great for simultaneous fixation and decal   formic acid and formaldehyde  
should be suspended in an embedding bag to expose all the surfaces of the specimen   specimen  
at the initial stage aids in infiltrating the specimen w/decal solution and will draw off carbon dioxide bubbles that form on the specimen surface   Vacuum  
migrate out of the tissue into the surrounding solution. solutions around the tissue may become saturated, so the solution should be changed frequently   calcium ions  
change frequently   solution  
never use _____to speed up decal process.   heat  
it increases the effects of decalcifying fluids on other tissue components, swelling and maceration will most likely occur   heat  
involves use of formic acid over a layer of an ammoniated salt of a sulfonated resin   Ion exchange resins  
exchanged for calcium ions, this keeps solution free of calcium ions and speeds up the reaction. solution doesnt need to be changed frequently   ammonium ions  
the best decal method   ion exchange resins  
utilizes a mixture of formic and hydrochloric acid placed in an apparatus based on a simple ectroplating device   electrolytic method  
The bone is attached to the anode (+) and a current is passed through the solution. The calcium ions (+ charge) are attracted to the cathode (-).   electrolytic method  
decal process takes 2-6hours, one sample per day can be processed.   electrolytic method  
heat generated by this method has a potential for tissue destruction, a total loss of cellular detail and stainability   electrolytic method  
organic compounds that have the property of binding certain metals   chelating agents  
ethylenediaminetetraacedic acid   EDTA  
solution should be between 5.0-7.2   Chelating agents  
Binds calcium ions   EDTA  
Very slow method but many enzyme methods can be used   chelating agents  
sectioning is difficult   underdecalcification of tissue  
stain is very poor   overdecalcified tissue  
three basic method - mechanical/physical, chemical, radiographic   end of decalcification  
testing flexibility of specimen, probing the specimen with needle or pin,   Mechanical method  
least desirable method, it is inaccurate and can create artifacts   mechanical method  
depends on the precipitation of calcium oxalate   Chemical method  
mixing a sample of the used decal solution w/a solution of ammonium hydroxide and ammonium oxalate. if solution remains turbid it indicates the presence of calcium   Chemical method  
keep retesting decal solution until free of calcium   Chemical method  
Yields a visual evidence that demineralization is complete. most accurate method.   Radiography  
Do not use on metallic fixed tissue such as Zenker or B-5 solution. metal will render the specimen radiopaque   Radiography  
wash tissue w/running wather or lithium carbonate to neutralize any remaining acid, then routinely process the specimen   after decalcification  
Glycol methacrylate is the most frequently used embedding media.   undecalcified bone  
section of bone may be ground with waterproof sandpaper to a thick of 75-100 microns. these ground sections may be stained and mounted on glass slides   undecalcified bone  
alcohol, buffered formalin or calcium formalin   fixatives of choice  
interefere with most techniques   metallic fixatives  
examined for diagnosis of metallic bone disease   undecalcified bone  
neutralizes remaining acid before processing the specimen   lithium carbonate  


   





 
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how
Created by: nperez on 2008-10-31



bad sites Copyright ©2001-2014  StudyStack LLC   All rights reserved.