摘要:

Two different histochemical methods for blocking the guanidinium group of arginine in formalin fixed, paraffin embedded material are reported here. One procedure uses diacetyl with short incubation times and high pH, the other uses the trimer of the diacetyl reagent and requires longer incubation times but moderate pH. The diacetyl reagent is recommended despite its high pH because the preparation of the diacetyl trimer is laborious and time-consuming.

ISSN:1052-0295    

DOI:10.3109/10520299409106254

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

This paper discusses the impact of both standardization and quality testing of dyes and stains in biology and medicine. After a brief review of why standardized dyes and stains are not presently available commercially, two types of testing and ways of improving dye quality are described. National or international organizations could be established to define standardization of dyes and stains. Standardization would be specifically defined as a list of physico-chemical parameters such as elaborated in this paper. Commercial batches of comparable quality may be labeled by the supplier as“standard dye.”a procedure currently performed by the European Council for Clinical and Laboratory Standardization (ECCLS). Also recommended to improve dye quality is commercial dye testing by independent laboratories with subsequent certification for use. This sort of quality control is currently carried out in the United States by the Biological Stain Commission (BSC). The advantages and disadvantages of both techniques and the use of image analysis for the definition of standards are discussed. A combination of both the BSC testing protocols and the ECCLS standards should be established for extended quality control of biological dyes and stains.

ISSN:1052-0295    

DOI:10.3109/10520299409106255

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

Glycosaminoglycans are identified in tissue sections by various histochemical techniques including staining with alcian blue and its analogues, such as cuprolinic blue and cupromeronic blue, or with high and low iron diamine methods. The variation in staining results is particularly confusing in the case of alcian blue, where not only are several different brands of alcian blue available but also several different staining protocols are used. If the results obtained by these techniques are compared, they often do not match. We have developed a dot blot technique for quality control of glycosaminoglycan histochemistry to standardize the staining protocols. This staining technique enables his-tochemists to test particular batches of alcian blue or its analogues for selective glycosaminoglycan staining, thus improving control of histochemical results. The results obtained using the dot blot assay indicate that it is necessary to test each batch of dye individually to obtain valid results in glycosaminoglycan histochemistry.

ISSN:1052-0295    

DOI:10.3109/10520299409106256

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

The organic solvent octane has been used routinely to permeabilize the hydrophobic vitelline membrane surrounding theDrosophilaembryo, thereby allowing the movement of small molecules into the egg. We present evidence that hexane is a more effective permeabilizing agent than octane and compare the effects of these solvents on uniformity of permeabilization and embryonic viability. The ability of each solvent to make the embryo accessible to a range of biological stains was compared. The effect of octane versus hexane permeabilization on subsequent embryonic viability was measured at seven different stages during early embryogenesis. We found that although hexane is a superior solvent for permeabilizing the vitelline membrane, it decreases the viability of embryos exposed between 0 and 3 hr of age. Older embryos treated with either hexane or octane are usually viable. We also showed that molecules with a molecular mass of 984 Daltons or more did not diffuse into the embryo following treatment with either hexane or octane. Results presented here challenge a phase-partition model that has been proposed previously to explain the molecular basis of permeabilization of theDrosophilaegg. An alternative model is described as well as an optimized protocol for permeabilizing and stainingDrosophilaembryos at any stage during early embryogenesis while maintaining viability for subsequent culture.

ISSN:1052-0295    

DOI:10.3109/10520299409106257

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

In situ hybridization was used to detect intracellularStaphylococcus aureusandS.epidermidisin mouse phagocytic cells after experimental infection of C3H mice withStaphylococcivia abdominal or intravenous injection. Isolated ascites or whole blood were tested by the phagocyte smear technique, using bacteriolytic enzymes to preserve phagocytic cell morphology. The exposed bacterial DNA was visualized as intracellular hybridized signals by use of biotinylated DNA probes and by immunocytochemistry using streptavidin-alkaline phosphatase conjugates as detector molecules. These DNA probes, prepared from randomly cloned genomic DNA fragments ofS. aureusand S.epidermidis, were strain-specific and did not cross-hybridize either in situ or on dot-blot hybridization. This technique of in situ hybridization with phagocyte smears is useful for detection and diagnosis of intracellular bacteria regardless of viability.

ISSN:1052-0295    

DOI:10.3109/10520299409106258

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

A home-made slam freezing device is presented that allows reproducible results in freezing various unfixed tissues. The heart of the device is an aluminium socket, which harbors a plunger that is set in motion by a spring. At the end of the plunger there is an electromagnet which holds the sample on a sheet metal planchette. During stop freezing the electrical contacts are interrupted and the plunger can be withdrawn leaving the specimen on the cooled copper block. This guarantees freezing of not only solid tissues, but also cell suspensions, such as blood or bone marrow.

ISSN:1052-0295    

DOI:10.3109/10520299409106259

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

Chromatography columns filled with Amberlite XAD-16 were used to decontaminate, using a continuous flow-through procedure, aqueous solutions of the following biological stains: acridine orange, alcian blue 8GX, alizarin red S, azure A, azure B, brilliant blue G, brilliant blue R, Congo red, cresyl violet acetate, crystal violet, eosin B, eosin Y, erythrosin B, ethidium bromide, Giemsa stain, Janus green B, methylene blue, neutral red, nigrosin, orcein, propidium iodide, rose Bengal, safranine O, toluidine blue O, and trypan blue. Adsorption was most efficient for stains of lower molecular weight (<600). Adsorption of stain increased as the flow rate decreased: column diameter had little effect on adsorption. Adsorption of stain was greatest when finely ground resin was used, but if the resin particles were too small, column clogging occurred. Limited grinding of the resin gave increased adsorption while retaining good flow characteristics. Amberlite XAD-16 saturated with methylene blue was regenerated to its initial adsorption capacity by passing methanol through the column. The technique described provides an economical, rapid means of removing stains from aqueous solution.

ISSN:1052-0295    

DOI:10.3109/10520299409106260

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

The immunohistological method described here permits re-examination of previously Feulgen stained quail-chick chimera tissues for vascular development using the monoclonal antibody QH1 which specifically recognizes quail hemangioblastic cells. Weigert's iron hematoxylin has been used to restore faded or bleached Feulgen stained chimeric avian tissues. Species-specific differences in nuclear morphology are as evident with iron hematoxylin staining as they are with Feulgen staining.

ISSN:1052-0295    

DOI:10.3109/10520299409106261

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

ISSN:1052-0295    

DOI:10.3109/10520299409106262

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor