Demonstration of the Ground Substance of Cartilage, Bone, and Teeth

A slab of bone about 5 mm. thick is decalcified in 5% HCl, washed, and placed for several days to 2-3 weeks in 3% KOH in 20% glycerin (if the bone is medium sized); for small bones the KOH should be decreased to 1%, and for large bones it may be increased to 5%. The solution is changed frequently. When the bone begins to dissociate, it should be removed and washed in water till all traces of alkali are removed. The specimen is passed through 3 changes of dioxane into paraffin, and then through a second paraffin bath into the final paraffin. Sections are cut at 10-12 μ and stained with VanGieson's picro-fuchsin or with orcein.     

A new method for identification of cement lines in undecalcified, plastic embedded sections of bone

A gallocyanin method for demonstrating cement lines in thin, undecalcified sections of bone has been developed that is compatible with prestaining with osteochrome before plastic embedding. After sectioning at 5 microns on the Jung K heavy duty microtome, the sections are attached to a microslide using Haupt's adhesive mounting medium, placed on a slide warmer at 37 C until completely dry, and deplasticized in xylene at 45 C for 16-24 hr. Sections are stained with 0.15% gallocyanin-5% chrome alum solution for 30 min, followed by staining in buffered Villanueva blood stain for 1-1 1/2 hr, quickly dehydrated, differentiated in equal parts xylene and 100% ethanol, cleared, and mounted in Eukitt's medium. Reversal lines appear as thin, scalloped, blue or purple lines approximately 0.3 micron wide, and arrest lines as thick, homogeneous, straight or evenly curved, dark blue or purple lines approximately 2 microns wide. The method also demonstrates abnormal halo volumes around osteocytes, old and new bone matrix, osteoid seams, and the granular mineralization front at the osteoid-bone interface. It promises to be valuable in the study of age-related bone loss, osteoporosis, and metabolic bone disease.     

A New Method for Identification of Cement Lines in Undecalcified, Plastic Embedded Sections of Bone

A gallocyanin method for demonstrating cement lines in thin, undecalcified sections of bone has been developed that is compatible with prestaining with ostcochrome before plastic embedding. After sectioning at 5 pm on the Jung K heavy duty microtome, the sections are attached to a microslide using Haupt's adhesive mounting medium, placed on a slide warmer at 37 C until completely dry, and deplasticized in xylene at 45 C for 16-44 hr. Sections are stained with 0.15% gallocyanin-5% chrome alum solution for 30 min, followed by staining in buffered Villanueva blood stain for 1-1 1/2 hr, quickly dehydrated, differentiated in equal parts xylene and 100% ethanol, cleared, and mounted in Eukitt's medium. Reversal lines appear as thin, scalloped, blue or purple lines approximately 0.3 pm wide, and arrest lines as thick, homogeneous, straight or evenly curved, dark blue or purple lines approximately 2 pm wide. The method also demonstrates abnormal halo volumes around ostcocytes, old and new bone matrix, osteoid seams, and the granular mineralization front at the osteoid-bone interface. It promises to be valuable in the study of age-related bone loss, osteoporosis, and metabolic bone disease.     

A Tetrachrome Stain for Fresh, Mineralized Bone Sections, Useful in the Diagnosis of Bone Diseases

Fresh, unprocessed bone is ground to sections 75-100 μ thick, stained in an aqueous solution composed of fast green FCF, 0.1 gm; orange G, 2.0 gm; distilled water, 100.0 ml; and adjusted to pH 6.65, then in a mixture of 1 part alcoholic solution of 0.25% celestine blue B and 9 parts of alcoholic solution of 0.1% basic fuchsin. Surface stain is removed by grinding sections to 50 μ and washing them in 1% invert soap (Zephiran) to remove adherent debris. (Commercial detergents and alkaline soaps may interfere with chromophore groups of the dyes.) Wash in tap water; rinse in distilled water and differentiate in 1% acetic alcohol. Dehydrate in ascending alcohols, clear in xylene and mount permanently in a neutral, synthetic resin. Active osteoid seams stain dark to light green; resting osteoid seams, red to bright orange red; transitional osteoid seams, geenish-yellow, orange red to red; older, partly mineralized matrix, orange; new, partly mineralized matrix, red; osteocyte nuclei, red; osteoblasts and osteoclasts, greenish-blue to dark purple nuclei and green or light green cytoplasm. Hyper-trophic and differentiating cartilage cells are stained light pink and dark red respectively. The staining reactions are consistent; the solutions are stable.     

Stain Technology a Bone Stain for Osteoid Seams in Fresh, Unembedded, Mineralized Bone

Fresh, ground, mineralized bone sections 75-100 μ thick are stained 90 minutes or 48 hours in the Bone Stain, a preparation containing fast green FCF, orange G, basic fuchsin, and azure II. Surface stain is then removed by grinding under running water. Sections are washed in 0.1% zephiran chloride (benzalkonium chloride) or in 0.01% mild soap and again washed in tap water, followed with distilled water. Sections are next differentiated in 0.01% acetic acid in 95% methanol, dehydrated in 95% ethanol and 100% ethanol, cleared in alcohol:xylene 1:1, 1:4, 1:9 and 2 changes of xylol, and then mounted permanently in Eukitt's mounting media.

Osteoid seams stain either green to jade green or red to dark red, incompletely mineralized bone red or orange yellow, and the zone of demarcation light green. The walls of lacunae, canaliculae, feathered bone, procedural artifacts and periosteocyte lacunar low-density versions stain red.

The method helps in the differential diagnosis of certain metabolic bone diseases in human biopsy and autopsy material.     

A Versatile New Mineralized Bone Stain for Simultaneous Assessment of Tetracycline and Osteoid Seams

A versatile mineralized bone stain (MIBS) for demonstrating osteoid seams and tetracycline fluorescence simultaneously in thin or thick undecalcified sections has been developed. Bone specimens are fixed in 70% ethanol, but 10% buffered formalin is permissible. Depending upon one's preference, these specimens can be left unstained or be prestained before plastic embedding. Osteoid seams are stained green to jade green, or light to dark purple. Mineralized bone matrix is unstained or green. Osteoblast and osteoclast nuclei are light to dark purple, cytoplasm varies from slightly gray to pink. The identification of osteoid seams by this method agrees closely with identification by in vivo tetracycline uptake using the same section from the same biopsy. The method demonstrates halo volumes, an abnormal, lacunar, low density bone around viable osteocytes in purple. This phenomenon is commonly seen in vitamin D-resistant rickets, fluorosis, renal osteodystrophy, hyperparathyroidism, and is sometimes seen in fluoride treated osteoporotic patients. In osteomalacic bone, most osteoid seams are irregularly stained as indicated by the presence of unmineralized osteoid between mineralized lamellae. The method has been used effectively in staining new bone formation in hydroxyapatite implants and bone grafts. Old, unstained, plastic embedded undecalcified sections are stained as well as fresh sections after removal of the coverslip. This stain also promises to be valuable in the study of different metabolic bone diseases from the point of view of remodeling, histomorphometry, and pathology.     

Hydrogen Chloride Gas for Effecting Staining of Internal Structures in Escherichia Coli.

The cells were smeared in water or water which had stood over about 10 mg. of magnesium powder per ml. for 30 minutes or longer. After the smear was dry and whitish in appearance it was held over a beaker of hot water (60-65° C.) until it was translucent or becoming translucent and exposed immediately to hydrogen chloride (gas) for a few seconds. After drying, it was covered with a 0.1% aqueous solution of neutral red for 5-8 minutes. The excess stain was washed from the slide with water and, while wet, placed in a saturated aqueous solution of mercuric nitrate for 5-15 seconds. The smear was rinsed in water and allowed to dry. When dry the slide was placed on a 50° C. warm plate and covered with a thin film of a 5% aqueous solution of nigrosin adjusted to a pH of about 3. The film dried quickly and upon cooling was ready for study. The stained material in the cells varied in shape and location with the moisture content of the smear and the time of exposure to hydrogen chloride. In the area of the smear directly exposed to the gas, the cells in general possessed a round or oval stained structure. Where there was little, if any, exposure to the gas the cells were uniformly stained. There were various gradations in the location and shape of the stained material in the cells from the one extreme to the other.     

A Naphthol Yellow S and Erythrosin B Staining Procedure for Use in Studies of the Acrosome Reaction of Rabbit Spermatozoa

Rabbit spermatozoa suspended in Krebs-Ringer-phosphate containing 0.25% glucose were smeared on polylysine-coated slides and dried in air at room temperature for 2 hr to overnight. Smears were stained in 0.1% naphthol yellow S in 1.0% acetic acid for 30 min at room temperature, blotted, rinsed in 1.0% aqueous acetic acid for 10-15 sec, drained and stained for 7 min in a mixture of equal parts of aqueous naphthol yellow S and erythrosin B (final concentration of each dye 0.1% w/v) at pH 4.6-5.0 (pH adjusted with acetic acid). Stained slides were well rinsed in distilled water adjusted to pH 4.65.0 with acetic acid, blotted, allowed to dry completely, rinsed in xylene and mounted in synthetic resin. Acrosomal caps were stained cherry-red (apical ridge) to pink (dorsal and ventral aspects); postnuclear caps stained pale pink; nuclei were either unstained or stained a very faint yellowish-pink. The mid-piece and flagellum were stained different shades of pink. The procedure is simple, rapid, and gives highly reproducible results. When present, acrosomes are easily detected regardless of the density of the smear.     

Adaptation of the Millon, Sudan Black B, and Periodic Acid-Schiff Technics for Block Staining of Insect Tissues

Spermatophores and reproductive systems of the beetle, Lytta nuttalli Say, fixed in Bouin's aqueous picroformol or buffered 10% neutral formol were stained in toto by the Millon, Sudan black B and periodic acid-Schiff reactions as follows. Millon: after excess fixative is removed in 70% ethanol, specimens are brought to water, stained in Millon's reagent at 60 C for 1 hr, rinsed in 2% aqueous nitric acid at 40-50 C, dehydrated rapidly, cleared, embedded and sectioned as usual. Sudan black B: specimens are taken to absolute ethanol, stained in a saturated solution of Sudan black B in absolute ethanol at room temperature for 24-48 hr, rinsed and cleared in xylene, embedded and sectioned. PAS: specimens are brought to water, oxidized in 0.5 aqueous HIO₄ at 37 C for 30 min, washed in 2 changes of water, stained in Schiif reagent at room temperature for 1 hr, rinsed in 3 changes of 0.5% aqueous potassium metabisulfite, washed in running water for 10-15 min, dehydrated, cleared, embedded and sectioned. All 3 methods produced their characteristic staining in specimens up to 3 mm thick     

Preparation of Thin Undecalcified Bone Sections by Rapid Manual Method

Sections from 3 μ to over 100 μ thick of fresh, unfixed, unembedded, unde-calcified and undehydrated bone are made by grinding 1 to 2 mm slabs of the desired orientation on waterproof carborundum abrasive paper, grit No. 320, 360 or 400. The manner of controlling the section is the crux of the technique. The section is held by wrapping a fresh strip of sandpaper around a 3″ × 1″ slide and accomplishing the grinding on a used piece of paper. The abrasive points on the fresh paper effectively prevent the section from sliding off the slide. The specimen is kept wet with water during the entire procedure. Sections are then stained, and excess surface stain can be ground off in similar fashion. After washing in dilute detergent solution to remove adherent derbis, the section is air dried and mounted in any nonacidifying resinous media. The method is suitable for wood and for fruit pits also.     

Preparation of Thin Undecalcified Bone Sections by Rapid Manual Method

Sections from 3 μ to over 100 μ thick of fresh, unfixed, unembedded, unde-calcified and undehydrated bone are made by grinding 1 to 2 mm slabs of the desired orientation on waterproof carborundum abrasive paper, grit No. 320, 360 or 400. The manner of controlling the section is the crux of the technique. The section is held by wrapping a fresh strip of sandpaper around a 3' × 1' slide and accomplishing the grinding on a used piece of paper. The abrasive points on the fresh paper effectively prevent the section from sliding off the slide. The specimen is kept wet with water during the entire procedure. Sections are then stained, and excess surface stain can be ground off in similar fashion. After washing in dilute detergent solution to remove adherent derbis, the section is air dried and mounted in any nonacidifying resinous media. The method is suitable for wood and for fruit pits also.     

A naphthol yellow S and erythrosin B staining procedure for use in studies of the acrosome reaction of rabbit spermatozoa.

Rabbit spermatozoa suspended in Krebs-Ringer-phosphate containing 0.25% glucose were smeared on polylysine-coated slides and dried in air at room temperature for 30 min at room temperature, blotted, rinsed in 1.0% aqueous acetic acid for 10-15 sec, drained and stained for 7 min in a mixture of equal parts of aqueous naphthol yellow S and erythrosin B (final concentration of each dye 0.1% w/v) at pH 4.6-5.0 (pH adjusted with acetic acid). Stained slides were well rinsed in distilled water adjusted to pH 4.6-5.0 with acetic acid, blotted, allowed to dry completely, rinsed in xylene and mounted in synthetic resin. Acrosomal caps were stained cherry-red (apical ridge) to pink (dorsal and ventral aspects); postnuclear caps stained pale pink; nuclei were either unstained or stained a very faint yellowish-pink. The mid-piece and flagellum were stained different shades of pink. The procedure is simple, rapid, and gives highly reproducible results. When present, acrosomes are easily detected regardless of the density of the smear.     

Silver Staining of Bone Prior to Decalcification for Quantitative Determination of Osteoid in Sections

Slices, 1-2 mm thick, of alcohol-fixed bone are immersed in 2% aqueous AgNO₃ in the dark for 48 hr. After thorough washing in running tap water, the silver phosphate formed at the interface of osteoid and calcified bone is reduced to a black deposit by 5% aqueous sodium hypophosphite containing 0.1 N NaOH, 0.2 ml/100 ml. The blocks are then immersed in 5% aqueous Na₂S₂O₃ and after further washing pass through a routine formic acid decalcification and paraffin wax embedding schedule. Sections cut at 5 μ thickness and counterstained with Van Gieson's picrofuchsin show a clear differentiation between osteoid tissue and the outer limit of calcification in trabecular or cortical bone, thus making them suitable for quantitative studies. The main advantage of the method is the production of intact stained sections without specialised embedding or cutting techniques.     

Permanent Mounts Of Chromosomes After 8-Oxyquinoline and Squashing

Fresh young root tips or free-hand cross sections thereof were placed in 0.002 M 8-oxyquinoline (aq.) at 10-14^oC. for 3 hours. After rinsing in water 1-2 minutes, they were soaked in N HC1 at 55^oC. for 25 minutes, rinsed again and squashed under a cover glass on a dry slide. Slide and cover glass were separated by placing in 70% alcohol and allowed to remain therein at least 0.5 hour after separation. Both slide and cover glass were passed through 50% and 30% alcohol to water and stained by the Feulgen procedure (without further hydrolysis) or with crystal violet after mordanting in 1% chromic acid overnight and washing in running water 3-4 hours. Dehydration and mounting in balsam completed the process. The smear on the slide was covered with a clean cover glass and the cover glass, bearing stained material, mounted separately.     

Carbol Fuchsin as A Stain for Human Chromosomes

Cells derived from cultures of bone marrow or leucocytes were treated with hypotonic citrate solution, squashed in 45% acetic acid frozen with CO₂ to allow removal of the cover glass without disturbing the smear, and stained by the following schedule: absolute alcohol, 5 min; coat with 0.2% parlodion and air dry; 70% alcohol, 5 min; distilled water, 5 min; stain 2-5 min in a mixture of 45 ml of a 0.3% solution of basic fuchsin in 5% phenol, 6 ml of glacial acetic acid, and 6 ml of 37% formaldehyde. Differentiate and dehydrate in absolute alcohol, clear in xylene and cover. The stain is durable for several weeks if slides are stored in darkness when not in use. Results resemble those obtained by Feulgen or aceto-orcein methods.     

A rapid procedure for routine double staining of cartilage and bone in fetal and adult animals

A simple, rapid procedure for dual staining of cartilage and bone in rodents, particularly in late gestation, has been developed for routine use. The procedure involves rapid, complete skinning of fresh eviscerated specimens following a 30 sec immersion in a 70 C water bath. The unfixed specimen is stained in a mixture of 0.14% Alcian blue and 0.12% alizarin red S in ethanol and glacial acetic acid. Specimens are then macerated in 2% KOH, cleared and hardened in 1:1 glycerin and distilled water, and stored in pure glycerin. Rapid staining of cartilage only is done in a mixture of 0.08% Alcian blue, glacial acetic acid, and ethanol, with subsequent maceration, clearing, and hardening as in the double staining procedure. Rapid staining of bone only, concurrent with maceration of soft tissue, can be done by placing fresh, unskinned specimens in a diluted mixture of alizarin red S in 2% KOH, with subsequent clearing and hardening in 1:1 distilled water and glycerin. Good quality fetal specimens can be prepared for examination by any of these procedures in a minimum of 11/2-2 days as compared to a minimum of 4-5 days for other procedures. Double stained specimens can be examined for abnormalities of the cartilage as well as bone.     

In Vivo Staining by Dis and Trisazo Dyes, Especially of Bone and Elastic Tissue

The localization and retention of dis and trisazo dyes in connective tissues and bone was studied in rats and rabbits. Chlorazol fast pink, 5% in 0.9% NaCl. was injected intraperitoneally, 25 mg/kg each day for 2 days in newborn, growing, mature and 17-18 day pregnant rats, and up to 5 days in young rabbits. The dye was also injected at different time intervals during the development of strontium-induced rickets in growing rats, and in animals with abscess walls following subcutaneous injection of 0.1 ml turpentine. Animals were killed at-intervals thereafter, and comparison of in vivo staining of 5% solutions of chlorazol fast pink, chlorantine fast red, chlorazol black E, chlorazol sky blue, chlorazol sky pink, chlorazol green, chlorazol violet, pontamine green and pontamine sky blue was made by intraperitoneal injection in rats. Soft and hard tissue specimens were embedded in polyester resin or in paraffin wax and sectioned at 5-7 μ. Chlorazol fast pink stained some connective tissues and growing bones. The main intensity of staining occurred within 24 hr and gradually decreased but was still detectable after 6 mo in elastic tissues. In thin plastic sections, colouration was brilliant, not in osteoid tissue, but at calcifying bone margins and in elastic fibres. Dye localized at calcifying bone margins was incorporated within calcified tissues and then subsequently lost through remodelling. Such staining was not seen in paraffin-embedded material. Dye uptake was greatly reduced in rachitic rats, and wide osteoid seams were coloured faint pink, but where calcification was still occurring, colouration was brilliant. Similarly collagenous tissue in abscess walls was only lightly stained, in contrast to brilliant colouration of elastic tissues and macrophages. Of the 9 dyes tested, only chlorazol fast pink and chlorazol sky blue stained bone and elastic tissue in vivo. This prolonged retention and staining by these 2 dyes, unlike the others, was associated with their presence in the proximal convoluted tubules of the kidney.     

The effect of diet calcium on fluoride toxicity in growing rats

The effect of dietary Ca in response to fluoride (F) treatment was investigated in rats. Rats were maintained on either adequate (0.5%) or high (2.0%) dietary Ca and given for 5 weeks, NaF in drinking water. The minimum NaF levels that inhibited body growth and reduced survival were 300 mg/L with 0.5% diet Ca and 550 mg/L with 2.0% diet Ca. With these toxic F doses, bone histology showed increased formation surfaces and thickened osteoid seams (osteoid index 6-7%). Fluoride doses 30% below toxic levels (200 and 350 mg/L for 0.5 and 2.0% diet Ca, respectively) had no demonstrable effect on bone. Additional diet Ca reduced F absorption from 76 +/- 3 to 47 +/- 3% for 0.5 and 2.0% diet Ca, respectively. Comparable absorbed doses of F produced comparable effects on bone and body growth but, with additional dietary Ca, these effects were observed with 50% lower serum and bone F levels. Variable response to NaF therapy can be produced in rats by alterations in dietary Ca alone. Results indicate that for clinical treatment the NaF dose needs to be adjusted on an individual basis but neither serum nor bone F levels can be used reliably to establish optimal doses.     

Basic Fuchsin-Crystal Violet; A Rapid Staining Sequence for Juxtaglomerular Granular Cells Embedded in Epoxy Resin

A basic fuchsin-crystal violet staining sequence for demonstration of juxtaglomerular granular cells in epoxy-embedded tissues is rapid and results in slides with excellent contrast and intensity. Procedure: Cut sections 0.3-0.6 μ thick. Hydrate through xylene and alcohol to water. Stain in modified Goodpasture's stain (basic fuchsin, 1; aniline, 1; phenol, 1; 30% alcohol, 100) for 20-30 sec; rinse in tap water; stain in modified Stirling's (crystal violet, 5; alcohol, 10; aniline, 2; water, 88) for 20-30 sec; rinse in tap water and dry on a hotplate; mount in a synthetic resin. Granular cells of the juxtaglomerular apparatus are stained an intense dark blue by the crystal violet. Arterial elastic membranes and collagen are pale blue. Other structures are shades of red.     

Camwood (Baphia nitida) Extract as a Histological Stain for Interglobular Dentine, Striated Muscle, and Counterstaining

The shavings of the dried heartwood of the tree Baphia nitida are ground to a fine powder, and 6 gm of the powder are extracted in 100 ml absolute ethanol at 27-30 for 6-24 hr. The extract is filtered with Whatman No. 1 paper and stored in a screw-capped bottle. For staining the interglobular dentine of nondecalcified sections of formlin-fixed teeth, sawed cross sections 20-30 μ thick were dehydrated in ethanol and stained in the undiluted extract for 6-12 hr at room temperature. The interglobular dentine was stained a bright golden brown on a pale brown background. For staining striated muscle, the extract was diluted 1:1 with distilled water and filtered. After mordanting formalin-fixed paraffin sections with 0.25% KMnO₄ for 5 min, and bleaching with 5% oxalic acid for 10 min, they were washed in water and stained for 2-24 hr at room temperature. The striations were stained light to deep golden brown. For use as a counterstain, a 1:6 dilution of the original extract was required. When applied after haematoxylin for 15-30 min, it stained tissue components in varying shades of golden brown with distribution comparable to that produced by 1% eosin.