| Question |
Answer |
| take out water | dehydrating |
| replace alcohol w/a reagent miscible w/parafin | clearing |
| impregnation, permeation | infiltration |
| infiltration w/a supporting medium | embedding |
| chem reagent that can be used for dehydrating and clearing steps in tissue processor. | universal solvent |
| volatile oils have odor of plant from which they are made | essential oil |
| water soluble (polyethylene glycols) | carbowax |
| substance that changes one ion for another. used in decalcification and exchange an ammonium ion for the calcium ion removed from tissue | ion exchange |
| absorbs water from air so use it over a drying chemical like drierite or an anhydrous calcium chloriee | acetone |
| removing calcium from bone | decalcification |
| must be mixable with both dehydrating agent and infiltration medium | clearing agents |
| organic compounds that have property of binding certain metals, | chelating agent |
| capable of mixing or being mixed | miscible |
| alcohol, dioxane, acetone, tetrahydrofuran | dehydrating agents |
| xylene, toluene, benzene, acetone, chloroform, cedarwood oil, tetrhydrofuran, dioxane, limonene derivatives, aliphatic hydrocarbons | clearing agents |
| infiltration medium | paraffin |
| dealcoholization agents | clearing agents |
| inadequate clearing | inadequate infiltration |
| soft, mushy tissue | inadequate clearing, inadequate infiltration results in |
| hard, brittle tissue | prolonged period in clearing agent |
| most widely used clearing agent, used in processing and staining | xylene |
| prolonged treatment w/xylene during processing | tissue becomes overhardened |
| rapid in displacing alcohol, mixiable w/paraffin | xylene |
| turns cloudy in presence of water | xylene |
| has PEL of 100ppm, use w/adequate ventilation | xylene |
| doesnt overharden as much as xylene | toluene |
| best aromatic clearing agent | toluene |
| fast acting, doesnt overharden like xylene | benzene |
| hardens muscle,tendon and uterus more than toluene | benzene |
| evaporates rapidly from paraffin bath | benzene |
| when using this clearing agent, the paraffin used for infiltration does not require rotaion and changing as frequently as w/o clearing agents | benzene |
| carcinoge, affects blood and bone marrow | benzene |
| leaves tissue less brittle than xylene | chloroform |
| penetrates slowly, makes clearing a longer process | chloroform |
| use in tightly covered containers | chloroform |
| desiccates (dries) connective tissue | chloroform |
| very volatile, makes fluid levels difficult to maintain in open processor | chloroform and benzene |
| causes formation of phosgene | heating chloroform |
| a toxic gas | phosgene |
| PEL 50ppm, it is carcinogenic | chloroform |
| low boiling point 58C, will boil off and be replaced by paraffin | acetone |
| can also be used for dehydration | acetone |
| Universal solvent | acetone |
| show more shrinkage than those cleared with xylene | tissues cleared w/acetone |
| are very volatile | essential oils |
| volality is not sufficient to allow ready replacment during paraffing infiltration | essential oils |
| if oil remains in tissue, microtomy is difficult | essential oils |
| remove w/an aromatic hydrocarbon clearing agent | essential oils |
| best known most widely used of the oils | cedarwood oil |
| clears alcohol dehydrated tissue quickly and doesnt cause further shrinkage | cedarwood oil |
| hardens and damages tissue less than and other known clearing agent | cedarwood oil |
| tissue may remain in this oil indefinitely | cedarwood oil |
| are expensive reagents and are not used routinely | essential oils |
| have become popular during last dacade and have a strong citrus odor | limonene reagents |
| irritant, sensitizer in concetrated from, causes allergic reactions | limonene reagents |
| causes difficulty breathing, headaches | limonene reagents |
| PELS are unavailable for inhalation toxicity | limonene reagents |
| harden tissue less than xyelene but they cause more contamination of the paraffin | limonene reagents |
| when used in staining, these reagents are greasier | limonene reagents |
| newest class of clearing agent | aliphatic hydrocarbons (alkanes) |
| they are low in reactivity and toxicity | aliphatic hydrocarbons (alkanes) |
| they are nonirritant and nonsensitizing | aliphatic hydrocarbons (alkanes) |
| they have an 8hour exposure limit of 300ppm | aliphatic hydrocarbons (alkanes) |
| used in histo, they penetrate tissue faster, remove fat effectively and allow coverslips to dry in usual manner | light weight (short chains)aliphatics |
| they dont tolerate water and they are incompatible with some mounting media | disadvantage of aliphatics |
| difficult to use in areas of high humidity | aliphatic hydrocarbons |
| can be used on all tissue processors and automated stainers | aliphatic hydrocarbons |
| not recommended for use on automatic coverslippers | aliphatic hydrocarbons |
| dioxane, tertiary butanol, tetrahydrofuran, acetone | universal solvent (dehydrating and clearing) |
| adequate reagent volume must be maintained | to ensure high quality tissue sections |
| have a schedule for the processor. rotate and change the reagents | to ensure consistant section quality |
| holds cells and intracellular structures, while thin sections are cut | embedding media |
| most popular embedding media, large amounts of tissue can be processed in a short time | paraffin |
| is inert mixture of hydrocarbons produced by craking of petroleum | paraffin |
| contains beeswax, rubber and other waxes or plastics | commercial paraffin |
| formed when the firs section cut adheres to microtome knife | ribbons |
| paraffin becomes harder and provides better support for hard tissue | melting point increases |
| wax becomes soft and provides less suport for hard tissue | melting point decreases |
| should be matched to the hardness of tissue to be sectioned | paraffin |
| enhance ability of paraffin compounds to provide support for hard tissues | additives |
| 55C to 58C | melting point of paraffin |
| tissue should remain in it the shortest time necessary for good infiltration | paraffin |
| prolonged heat causes shrinkage and hardening | paraffin |
| keep supply at 2C to 4C above the melting point | paraffin supply |
| tissues exposed to overheated paraffin will overhaden, and section quality will be changed, tissue will not be effected | paraffin |
| must be recorded daily | paraffin temp |
| will become contaminated w/clearing agentm, if it is not changed and monitored frequently | paraffin |
| three changes of paraffin are recommended | for infiltration |
| aided by vacumm | paraffin infiltration |
| staining problems | overprocessing |
| difficult to process on the same processing cycle should be processed overinght on an open processor w/o heat and vaccum | bx, uterus, breast and large specimens |
| dehydrates | alcohol |
| PEL 1,000 ppm | Ethyl alcohol |
| clear,colorless,flammable | Ethyl alcohol |
| drinkable, controlled by federal goverment, troublesome record keeping is required, reliable, fast acting, best dehydrant | Ethyl alcohol |
| is hydrophillic | Ethyl alcohol |
| mixable with water as well as organic solvents in all proportions | Ethyl alcohol |
| should be used in sequence of solutions that gradually increase in concentration | Ethyl alcohol |
| dehydration process is started at 95%, followed by absolute alcohol | Ehtyl alcohol |
| causes excessive shrinkage and hardening | Ethyl alcohol |
| poisonous and rarely used | Methyl alcohol |
| flammable, unpleasant odor, clear, colorless | Methyl alcohol |
| PEL of 200 | Methyl alcohol |
| overexposure causes blindness and death | Methyl alcohol |
| substitute for ethanol | isopropanol |
| no goverment restrictions. doesnt harden or shrink tissue as much as ethanol | isopropanol |
| mildly irratant to eyes, nose, throat | isopropanol |
| PEL of 400 ppm | isopropanol |
| good dehydrant for plant and animal | butanol |
| pronounced odor and low dehydrating power.requires long period for dehydration | butanol |
| excellent dehydrant for slow processing | butanol |
| causes less shrinkage and hardening than ethanol | butanol |
| rapid reacting, less expensive, causes excessive shrinkage | acetone |
| PEL 1,000ppm | acetone |
| flammable, flash point of -17c | acetone |
| referred to as emebedding medium. holds cells and intracellular structures in proper relationship while thin sections are cut | infiltration media |
| Where the tissue cassettes are transported from one solution to next | open system processor |
| no vacuum used | open system processor |
| the tissue is stationary and fluids are pumped in and out of the closed chamber holding the tissue cassette | closed system processor |
| uses vacuum | closed system processor |
| different protocols based on open or closed system | processor solutions and times |
| shorter processing cycle is used for bx specimens so they wont be overhardened | processing time |
| casting or blocking | embedding |
| enclosing the tissue in the infiltration medium used for processing and then allowing the medium to solidify | embedding |
| is determined by the embedding medium used | method of processing |
| side down in the cassette is the side down in the mold | embedding reminders |
| upside can be notched or inked | embedding reminders |
| tissue should be in center of mold | embedding reminders |
| light pressure should be applied over the entire tissue during orientation and light chilling | embedding reminders |
| wipe forceps inbetween samples to prevent forcep metastasis | embedding reminders |
| place in a line parallel to the longer axis on the mold | multiple pieces |
| shuld be facing one side of the mold not up or down | the epithelium |
| embed on diagnol to aid in the ease of sectioning | bone |
| GI tract, cysts and gall bladder | tissue w/a wall |
| embed on an edge so all layers are showing | GI tract, cysts and gall bladder (tissue w/a wall) |
| fallopian tubes, appendix and arteries | Tubular structures |
| embed in a cross section so that the lume and all mucosa, submucosa and external muscle layers are obvious | fallopian tubes, appendix and arteries (tubular structures) |
| micible w/ lower alcohols, water, ether, chloroform, acetone, benzene, toluene, xylene and melted paraffing | tetrahydrofuran |
| same as dioxane in use but less expensive | tetrahydrofuran |
| acts rapidly w/o causing excessive shrinkage and hardening | tetrahydrofuran |
| can be used to dehydrate and clear stained slides | tetrahydrofuran |
| best universal solvent | tetrahydrofuran |
| very volatile, offensive odor, explosive peroxides may form, can cause conjuntivities, use in well ventilated room | tetrahydrofuran |
| produces less shrinkage than ethanol | dioxane |
| faster dehydrant than ethanol but m/b used in larger volumes | dioxane |
| can be reused by treating anhydrous calcium chloride or calcium oxide | dioxane |
| it has water in it, so if itis left in the tissue, it may shrink it up to 50% during infiltration | dioxane |
| cummulatively toxic, pronounced odor, rarely used | dioxane |
| Osha PEL 100ppm, NIOSH PEL 1ppm, carcinogen, flammable | dioxane |
| expensive, tends to solidify at room temp | tertieary butanol |
| most satisfacory method of obtaining F.s. from formalin fxd tissue | 30% sucrose |
| micible w/ lower alcohols, water, ether, chloroform, acetone, benzene, toluene, xylene and melted paraffing | tetrahydrofuran |
| same as dioxane in use but less expensive | tetrahydrofuran |
| acts rapidly w/o causing excessive shrinkage and hardening | tetrahydrofuran |
| can be used to dehydrate and clear stained slides | tetrahydrofuran |
| best universal solvent | tetrahydrofuran |
| very volatile, offensive odor, explosive peroxides may form, can cause conjuntivities, use in well ventilated room | tetrahydrofuran |
| produces less shrinkage than ethanol | dioxane |
| faster dehydrant than ethanol but m/b used in larger volumes | dioxane |
| can be reused by treating anhydrous calcium chloride or calcium oxide | dioxane |
| it has water in it, so if itis left in the tissue, it may shrink it up to 50% during infiltration | dioxane |
| cummulatively toxic, pronounced odor, rarely used | dioxane |
| Osha PEL 100ppm, NIOSH PEL 1ppm, carcinogen, flammable | dioxane |
| expensive, tends to solidify at room temp | tertieary butanol |
| inital paraffin infiltration must be half tertiary butanol and half paraffin | tertiary butanol |
| can be used as a dehydrant in the staining process | tertiary butanol |
| odorus, PEL 100ppm | tertiary butanol |
| Dealcoholization | clearing |
| the removal of alcohol, to make tissue receptive to the infiltration medium | clearing |
| used for processing of tissue and staining of microscopic sections | clearing |
| hard brittle tissue, sectioning difficult | excessive clearing |
| reduces crystal size and increases stickiness and adhesion | beeswax |
| reduces brittleness, increases stickiness and maes the formation of ribbons during sectioning | rubber |
| other waxes produce smooth texture and smaller crystal size | Paraffin composition |
| beeswax,rubber and other waxes | Paraffin composition |
| increases the hardness and support | plastics |
| infiltrate tissue directly from aqueous fixative | water soluble waxes |
| will not infiltrate tissue containing large amounts of fat | carbowax |
| cryoprotectant | 30% sucrose |
mr. charles11
