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F S Waldrop

Publications and source records attributed to F S Waldrop.

12 recordsLinked to original sources
PubMed1986

Application of current chemical concepts to metal-hematein and -brazilein stains.

Current chemical concepts were applied to Weigert's, M. Heidenhain's and Verhoeff's iron hemateins, Mayer's acid hemalum stain and the corresponding brazilein compounds. Fe bonds tightly to oxygen in preference to nitrogen and is unlikely to react with lysyl and arginyl groups of proteins. Binding of unoxidized hematoxylin by various substrates has long been known to professional dyers and was ascribed to hydrogen bonding. Chemical data on the uptake of phenols support this theory. Molecular models indicate a nonplanar configuration of hematoxylin and brazilin. The traditional quinonoid formula of hematein and brazilein was revised. During chelate formation each of the two oxy- groups of the dye shares an electron pair with the metal and contributes a negative charge to the chelate. Consequently, the blue or black 2:1 (dye:metal) complexes are anionic. Olation of such chelates affects the staining properties of iron hematein solutions. The color changes upon oxidation of hematoxylin, reaction of hematein with metals, and during exposure of chelates to acids can be explained by molecular orbital theory. Without differentiation or acid in dye chelate solutions, staining patterns are a function of the metal. Reactions of acidified solutions are determined by the affinities of the dye ligands. Brazilein is much more acid-sensitive than hematein. This difference can be ascribed to the lack of a second free phenolic -OH group in brazilein, i.e. one hydrogen bond is insufficient to anchor the dye to tissues. Since hematein and brazilein are identical in all other respects, their differences in affinity cannot be explained by van der Waals, electrostatic, hydrophobic or other forces.

Aorta↗
PubMed1985

A comparative study of myosins and prekeratin in epithelial cells of methacarn-fixed tissues.

Around the turn of the century, tonofibrils and contractile myofibrils were observed within the same cells. These findings have been largely forgotten. To clarify the topical relations of these proteins in epithelial cells, duplicate sections of methacarn-fixed human and canine tissues were treated with the tannic acid-phosphomolybdic acid (TP)-Levanol Fast Cyanine 5RN reaction for myosins and the PAP technic for prekeratin, respectively. In bronchi, lingual and sweat glands, liver and pancreas, myosin was confined to the terminal bar-terminal web system, including pericanalicular layers. Prekeratin occurred throughout the epithelium of bronchi and ducts; secretory cells showed little or no reaction. Observations on myosin in kidney confirmed data by Harper et al. (1970). The PAP technic colored transitional epithelium and collecting tubules intensely; convoluted tubules did not react. Staining of segments of Henle's loops varied from case to case. Both reactions colored thymic epithelial cells. In myoid cells of Hassall's corpuscles myosin was gradually replaced by prekeratin and keratin. Basal cells of epididymis reacted strongly with the PAP technic, but did not contain myosin. Prekeratin is apparently identical with epidermin, whose composition and structure were well known in the 1950's. Epidermin undergoes chemical changes as cells move from the stratum basale to the stratum corneum. According to DAKO, the antibodies used in this study were prepared with prekeratin extracted from stratum corneum. Data in the literature and observations in this investigation indicate that some samples of antibodies do not react with all tonofilaments.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetates↗
PubMed1985

A review of light, polarization and fluorescence microscopic methods for amyloid.

Traditional technics for amyloid are not always dependable. Therefore, several reactions, which do not require differentiation, were developed in this laboratory. This review describes technics that proved suitable for diagnostic pathology, including polarization and fluorescence microscopy. Effects of fixation on the reactivity of amyloid are also considered. The chemical mechanism of the alkaline Congo red, Mesitol WLS-Congo red and Phorwhite BBU reaction, and of a modified thioflavine T stain are reviewed briefly. Problems encountered with other methods, which cannot be recommended for diagnostic pathology, are outlined.

Amyloid↗
PubMed1979

Aldehyde-fuchsin: historical and chemical considerations.

The staining mechanisms of Gomori's aldehyde-fuchsin are not yet fully understood. It seemed therefore timely to review the history of this dye class in context with current dye and aldehyde chemistry. In 1861 Lauth treated basic fuchsin with acetaldehyde. This dye became known as Aldehyde Blue, but consisted of violet and blue dyes. Schiff (1866) studied several aldehyde-fuchsins; these compounds contained two molecules of dye and three molecules of aldehyde. Acetaldehyde-fuchsin prepared according to Schiff's directions showed staining properties similar to those of Gomori's aldehyde-fuchsin. This dye class was soon superseded by new dyes more suitable for textile dyeing, and chemical investigations of aldehyde-fuchsins ceased around the turn of the century. Gomori's aldehyde-fuchsin has been regarded as a Schiff base. However, according to chemical data, low molecular aliphatic aldehydes and aromatic amines tend to form condensation products. Correlations of chemical and histochemical observations suggest such processes during aging of dye solutions. Models of dimers and polymers of aldehyde-fuchsin could be built without steric hindrance. The nature of the bonds formed by various components of aldehyde-fuchsin solutions is not clear. However, cystine in proteins, e.g. in basement membranes, apparently does not play a role in the binding of aldehyde-fuchsin by unoxidized Carnoy- or methacarn-fixed sections.

Aldehydes↗
PubMed1979

Histochemical observations on Pneumocystis carinii: selective demonstration of honeycomb forms.

Histochemical investigations of pulmonary lesions indicated selective coloration of membranes of honeycomb stages of Pneumocystis carinii by the periodic acid--sodium bisulfite--resorcin-fuchsin reaction for basement membranes; mucus, fibrin and other deposits in respiratory pathways did not react. These membranes were colored selectively also by the picro-Sirius Red F3BA method for collagens; fungi in tissues from patients with candidiasis remained unstained. For simultaneous demonstration of honeycomb and cyst forms of Pneumocystis carinii, sections were prestained with Grocott's modification of Gomori's methenamine-silver nitrate technic and then treated with the periodic acid-Schiff (PAS) or picro-Sirius Red F3BA reaction. In contrast to other Gram-positive microorganisms, cysts of Pneumocystis carinii were immediately decolorized by acetone-ether mixtures; this indicates differences in the mode of dye binding. Frequently, only one stage of Pneumocystis carinii was found in a given area. Hence a combination of reactions showing different stages is recommended for studies of small tissue samples.

Basement Membrane↗
PubMed1979

On the mechanism of Verhoeff's elastica stain: a convenient stain for myelin sheaths.

Verhoeff (1908) recommended an iron-hematein formula containing Lugol's solution for demonstration of elastic tissue; sections are differentiated until desired staining patterns are obtained. Verhoeff's stain colored a variety of tissue structures and showed higher substantivity for myelin sheaths than for elastin. Addition of HCL or omission of Lugol's solution decreased or abolished coloration of pseudo-elastica and thus enhanced selectivity for elastin. Substitution of Fe++ for Fe+++ abolished dye binding by elastin. A review of chemical data indicated interaction of components of Lugol's solution with the dye. Hematein and Fe+++ form a variety of cationic, anionic and non-ionic chelates; the ratio of these compounds changes with time. Dye binding apparently occurs mainly via van der Waals forces and hydrogen bonds. Verhoeff's elastica stain is definitely not specific for elastin and is inferior to orcein and resorcin-fuchsin because of the required differentiation with its inherent bias to produce patterns which conform to expectations. However, Verhoeff's elastica stain is far superior to other metal-hematein technics for myelin sheaths. The combined Verhoeff-picro-Sirius Red F3BA stain can be performed in 30 min and does not require differentiation. It is therefore suggested to reclassify Verhoeff's elastica stain as a method for myelin sheaths.

Aorta↗
PubMed1976

Light microscopic demonstration of myoid material in nuclei.

During the development of configurational staining methods for proteins of the myosin-fibrin group, nuclei showed staining properties similar to those of myofibrils. This dye binding could be attributed to nuclear alpha-helical proteins. More recent chemical and electron microscopic studies demonstrated actomyosins in nuclei of various species. Possible roles of nuclear actomyosin in chromosome movements and condensation and in cell proliferation have been suggested. It seems therefore permissible to assume that the tannic acid-phosphomolybdic acid (TP)-Levanol Fast Cyanine 5RN method and similar technics visualize myosin in nuclei. Comparative studies of actomyosins from various sites indicated significant chemical an histochemical differences. It is therefore suggested that, in analogy to the different classes of collagens, there may be several subgroups of myosin which differ in their physico-chemical properties and sensitivity to fixation procedures and pathological conditions.

Actomyosin↗
PubMed1976

Staining of keratin and keratohyalin with the reactive dye levafix red violet E-2BL.

Demonstration of keratin in Zenker-fixed skin and in tissues stored in formalin can be difficult because such material is unsuitable for histochemical studies. A reactive dye, Levafix red violet E-2BL, proved useful for demonstration of keratohyalin and some types of keratin. Formalin-, Zenker- and methacarn-fixed sections were pretreated with alkaline alcohol, stained one hour at 60 C in an aqueous solution containing 0.25% Levafix red violet E-2BL plus 0.25% NaCl, rinsed in buffer solution pH 9, dehydrated and mounted. Keratohyalin granules and stratum corneum were colored red violet; hair and tonofibrils remained unstained. In sections prestained with Mayer's acid hemalum, keratohyalin was dark blue. Sulfonated monoazo dyes without reactive groups colored no tissue structures under the conditions of this technic; apparently, Levafix red violet E-2BL is bound via its reactive group. Polarization microscopic studies suggest binding of Levafix red violet E-2BL by an amorphous matrix of keratin. Correlations with chemical data indicate that the staining patterns parallel the distribution of proteins formed in the stratum granulosum.

Azo Compounds↗
PubMed1976

Alterations of the myoid pericanalicular layer in liver. A light microscopical pilot study of human autopsy material.

Previous histochemical studies demonstrated a myoid layer along biliary pathways. This report describes alterations of the pericanalicular layer in various lesions. Carnoy- or methacarn-fixed sections of livers from 200 autopsies were treated with the tannic acid-phosphomolybdic acid-dye method for myosins. In other series, methods for myosins were combined with the picro-Sirius Red F3BA stain or the Prussian Blue reaction. In normal liver, bile canaliculi were lined by a narrow myoid layer. In other cases, eg, hepatic cirrhosis, the pericanalicular layer showed slight to moderate thickening. In cases with obstruction or atresia of bile ducts, the dilated canaliculi were surrounded by a prominent myoid layer. These observations support theories that the pericanalicular layer is contractile and promotes bile flow under positive pressure.

Bile Ducts, Intrahepatic↗
PubMed1975

Myoid fibrils in epithelial cells: studies of intestine, biliary and pancreatic pathways, trachea, bronchi, and testis.

Cytoplasmic filaments have been studied extensively by electron microscopy, but the histochemical nature of such fibrils in non-keratinizing epithelia has not been systematically investigated. During studies of early arterial lesions we observed structures with the staining properties of myosins in epithelial cells of various organs. The configurational staining, polarization and fluorescence microscopic properties of these myoid structures were compared with those of myofibrils in smooth muscle and classical myoepithelial cells. The following structures showed the characteristics of myofibrils: the terminal web in columnar epithelial cells of intestine, trachea, bronchi, bile ducts, pancreatic ducts and ductus epididymidis, the pericanalicular layer of bile and pancreatic canaliculi, fibers in the caudal tube of spermatids and the flagella of spermatozoa. Cilia, e.g. of respiratory epithelium, tonofibrils in squamous epithelium and nerve axons did not react. These studies indicate significant histochemical differences between cytoplasmic filaments. Different types of intracellular fibrils can be found in the same cell, e.g. in respiratory epithelium.

Bile Ducts, Intrahepatic↗
PubMed1975

Luxol Fast Blue MBSN-Levafix Red Violet E-2BL. A combined stain for myelin sheaths and glia fibers.

During investigations of reactive dyes, Levafix Red Violet E-2BL was found suitable for staining of glia fibers. Experiments were carried out on 37% formaldehyde-fixed human autopsy material. Paraffin sections were treated with Luxol Fast Blue MBSN as usual, differentiated until glia fibers were decolorized, and counter-stained in a 0.25% solution of Levafix Red Violet E-2BL in 0.25% acetic acid. Myelin sheaths were colored blue. Gila fibers, smooth muscle cells, and nuclei were stained red violet. Axons and connective tissue remained unstained; occasionally, coarse bundles of collagen showed patchy coloration. Polarization microscopic studies proved that Levafix Red Violet E-2BL is bound to well-oriented fibrous proteins in glia fibers. The similar staining and polarization microscopic properties of glia fibers and smooth muscle support previous findings that glia fibers contain a myosin-like protein.

Brain↗