PRELIM: CH8 Decal (3)

10%

Which concentration of formic acid is described as the best all-around decalcifier?

Small bone pieces and teeth when good morphology is desired

Which specimen type is particularly appropriate for formic acid decalcification?

It is gentler and generally preserves tissue morphology better than strong acids

Why might formic acid be favored when immunohistochemical staining is planned?

Trichloroacetic acid

TCA stands for:

Small spicules of bone

Trichloroacetic acid is best suited for:

It can function as both a fixative and decalcifying agent

Which statement about chromic acid/Flemming's fluid is correct?

It is highly corrosive and carcinogenic

Why is chromic acid a major laboratory safety concern?

They require appropriate hazardous-waste disposal rather than drain disposal

Which statement about chromium-containing solutions is correct?

Citric acid-citrate buffer

Which decalcifying solution is characterized by a pH of approximately 4.5 and excellent nuclear and cytoplasmic staining?

It acts too slowly for routine purposes

What is the major limitation of the citric acid-citrate buffer solution?

Neutral EDTA decalcification

A researcher needs maximum preservation of DNA for polymerase chain reaction (PCR). Which approach is most appropriate?

Polymerase Chain Reaction

PCR stands for:

Fluorescent In Situ Hybridization

FISH stands for:

It is slow but causes less damage to molecular and tissue components

Why is EDTA particularly useful for research involving IHC (Immunohistochemistry), FISH (Fluorescent In Situ Hybridization), or PCR (Polymerase Chain Reaction)?

14%

What is the approximate concentration of EDTA commonly used for decalcification in the notes?

7–7.6

What is the optimal pH range generally recommended for neutral EDTA decalcification?

The rate of calcium removal and tissue preservation are influenced by pH

Why is maintaining the appropriate pH important when using EDTA?

Tissue maceration may begin because of damage to alkaline-sensitive protein bonds

What may happen when EDTA is used at excessively alkaline pH?

6–8 weeks or longer

Approximately how long may dense cortical bone require for complete EDTA decalcification?

Approximately every 3 days, and daily during the final stage

How often should the EDTA solution generally be changed during decalcification?

Sonication with EDTA

A laboratory wants to accelerate EDTA decalcification but is concerned about preserving tissue for molecular analysis. Which technique has been successfully used for this purpose?

It removes calcium ions from the decalcifying solution, helping maintain the solution's effectiveness

What is the main principle behind an ion-exchange resin used in decalcification?

Formic acid-containing decalcifying solutions

Ion-exchange resin is particularly useful with:

Electrophoresis/electrical ionization

Which method uses a negative electrode to attract positively charged calcium ions during decalcification?

X-ray examination of the specimen

A large femoral head has been undergoing acid decalcification. The laboratory wants the most sensitive and reliable method to determine whether tiny residual calcium deposits remain. Which method should be selected?