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Biomedical subjects

H Franz

Publications and source records attributed to H Franz.

At least 91 records · Page 5Linked to original sources
PubMed1980

Electron microscopic visualization by the unlabelled lectin/antiferritin-antibody/ferritin method of lectin receptors on cell surfaces.

For electron microscopic demonstration of carbohydrate moieties on cell surfaces of HeLa-cells the lectins from Viscum albumin, Canavalia ensiformis and Dolichos biflorus have been used. The staining experiments were performed by reaction of the cell surface receptor localized lectin with purified antiferritin-antibody followed by ferritin. The three-step reaction cell surface receptors leads to lectin leads to antiferritin antibody leads to ferritin is proposed as general method for electron microscopic localization of lectin receptors without covalent coupling.

Antibodies↗
PubMed1980

[Purification and specificity control of labelled antibodies (author's transl)].

A review is given about causes of unspecific binding and the possibility of its prevention. Unspecific binding can be caused by: binding of proteins and glycoproteins on cells or tissues by non-covalent links, undesirable antigen-antibody-reactions, non-immune affinity reactions, changes of the charge of antibodies depending on the labelling procedure. A method for fractionation of labelled antibodies by using precipitation with protamine sulphate is described.

Animals↗
PubMed1979

Combination of immunological and lectin reactions in affinity histochemistry: proposition of the term affinitin.

Using the series system cell receptor leads to mistletoe lectin leads to antiferritin-antibody leads to ferritin, the possibilities for combination of lectin and immunological reactions for histochemistry are discussed. The system cell antigen leads to antibody leads to labelled mistletoe (or other) lectin is recommended for visualization of cell antigens (mistletoe lectin as common immunoglobulin reagent). It is pointed out that lectin reactions do not belong to immunhistochemistry but to affinity histochemistry. For all receptor specific proteins (antibodies, lectins, enzymes, haptoglobin and other) the term affinitin is proposed. In consideration of this new definition a common scheme is formulated: Affinitin reacts with affinitin receptor forming affinity product.

Animals↗
PubMed1979

Affinity chromatography of human serum proteins using matrix bound lectin from Viscum album L.

The D-galactose specific lectin from Viscum album L. reacts with serum proteins that contain the corresponding D-galactopyranosyl residues. By affinity chromatography of human serum on lectin-sepharose IgM, alpha 2-macroglobulin, haptoglobin and beta-lipoprotein were quantitatively retained. Only parts of IgA, IgG and transferrin were retarded. The other serum proteins are unbounded as albumin, beta 1 A- and beta 1 C-globulin.

Chromatography, Affinity↗
PubMed1979

Affinity chromatography of human serum proteins using matrix bound lectins from Viscum album and Vicia faba.

The D-galactose specific lectin from Viscum album and the D-mannose specific lectin from Vicia faba react with serum proteins which contain the corresponding carboyhydrate moieties. By affinity chromatography of human serum using the combination of insolubilized lectins coupled to Sepharose it is possible to fractionate serum proteins in 3 groups: 1. proteins which react with both of the lectins; 2. proteins which react only with one of the lectins; 3. proteins which do not display any affinity for one of the two lectins.

Blood Proteins↗
PubMed1979

Chemical modification studies on the D-galactopyranosyl binding lectin from the mistletoe Viscum album L.

The role of amino, sulfhydryl, disulfide, carboxyl, phenolic, imidazole and indole groups on the agglutination of human erythrocytes by the lectin from Viscum album has been determined using specific chemical modification techniques. The results indicate that tyrosine residues participate in the hemagglutination reaction. Subunits of the lectin possess only reduced hemagglutinating ability.

Borohydrides↗
PubMed1978

[Electronmicroscopic-histochemical demonstration of acid mucopolysaccharides using cationic ferrocenyl compounds (author's transl)].

Long-chain ammonium compounds with ferrocenyl groups were synthesized and used for the light (sudanophilia) and electron microscopic (electron dense staining by the iron of the ferrocenyl group) localisation of acid mucopolysaccharides. At least 5 of the 39 prepared ammonium salts produce a very good contrast. Cetyl-ferrocenylmethyl-dimethyl ammonium chloride has been found to be the best blocking agent and stain for acid polysaccharides.

Animals↗
PubMed1978

[Use of ferritin conjugates of a lectin from mistletoe (Viscum album L.) for the electron microscopic localization of cell surface receptors].

Ferritin conjugates of a lectin from mistletoe (Viscum album L.) were used for the electron-microscopic demonstration of carbohydrate receptors on the cell surface of human erythrocytes and murine tumor cells. Human A1 erythrocytes showed only a slight focal binding of ferritin. Cells of the mouse ascites tumor strain L 1210 were labelled very tightly on their surface and incorporate the ferritin by pinocytosis. Furthermore they showed cytotoxic changes in their ultrastructure. In the presence of galactose the labelling on the surface, the incorporation of the conjugate within the cell as well as the cytotoxicity were inhibited.

Animals↗
PubMed1977

[Apoplexy (author's transl)].

Apoplexy is a common clinical picture. The clinical diagnosis is unsatisfactory. The procedure hitherto, in which angiographic clarification of the intracranial space-occupying lesions and of the extracranial vascular changes is almost always performed, will change with the introduction of computer tomography in favor of the bloodless method (Doppler echography). Angiography will then only be carried out in proven hemodynamically active stenosis after the neurological symptoms have receded. The treatment of ischemic cerebral disease is a task for the hospital. Transient ischemic attacks also require hospital supervision, preferably under conditions of intensive care. In addition to support from infusions and digitalization, Actovegin infusions are standard therapy.

Acute Disease↗
PubMed1977

Sudan Black B: chemical structure and histochemistry of the blue main components.

Sudan Black B contains two blue main components, SSB-I and SSB-II. Their chemical structures were determinated by the aid of two-dimensional thin-layer chromatography, column chromatography, absorption, IR, mass, H1-NMR, and C13-NMR spectroscopy and were proved by alternate synthesis. SSB-I has been found to be 2,3-dihydro-2,2-dimethyl4-[(4-phenylazo-1-naphthalenyl)-azol]-1H-perimidine. For SSB-II was confirmed the known structure 2,3-dihydro-2,2-dimethyl-6-[(4-phenylazo-1-naphthalenyl)-azo]-1H-permidine. Relations of chemical structure of SSB-I and SSB-II to their staining properties are discussed.

Azo Compounds↗
PubMed1977

Immunochemical studies on phenylalanyl-tRNA synthetase from Escherichia coli.

Antibodies against the alpha and beta subunits of phenylalanyl-tRNA synthetase were fractionated by ion exchange chromatography into different classes and then digested with papain to yield the respective Fab fragments. The preparations obtained were used to investigate (i) whether the alpha and beta polypeptides share any common antigenic determinants and (ii) whether immunological methods are able to resolve the catalytic function of the subunits of this enzyme (or principally of oligomeric enzymes). As to the first problem, immunodiffusion and complement fixation experiments showed that there is no immunological relatedness between the subunits which argues against the existence of sequence homoligies. As to the second question investigated, it was found that any binding of immunoglobulins of Fab fragments to the alpha or the the beta subunit affects enzyme activity either in the direction of activation or inhibition. These results therefore show that the immunological approach is not appropriate for resolving subunit-specific funcitons, possibly as a consequence of conformational changes induced in the enzyme by the binding of the immunoglobulins of Fab fragments.

Amino Acyl-tRNA Synthetases↗