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Biomedical subjects

W Köhler

Publications and source records attributed to W Köhler.

At least 163 records · Page 9Linked to original sources
PubMed1982

[Haptoglobins, streptococcus agglutination and streptococcal infections].

The haptoglobins in man and in mammals react with streptococci bearing the T4-antigen. Hp 2-2 and Hp 2-1 react with high titres like complete agglutinins while Hp 1-1 acts like a blocking antibody. It is surprising to observe the similarity of the behaviour of the haptoglobins and of IgG and IgM. Streptococci carrying Hp 1-1 yield a positive Coombs-test. The Coombs-serum however, is an anti-human-haptoglobin-body from sheep. By means of supplements it has been possible to increase partly considerably the titres of Hp 2-1 and Hp 2-2 against the streptococci.

Agglutination↗
PubMed1982

[Induction of immune interferon by erythrogenic toxins A and B from Streptococcus pyogenes].

By interaction of streptococcal erythrogenic toxins A and B with chick embryo fibroblasts and human amnion (FL) cells an antiviral interferon-like factor was secreted. It inhibited the replication of vesicular stomatitis, vaccinia and Mengo viruses. The streptococcal toxin type B was 50 times more cytotoxic for both cell cultures in comparison with streptococcal toxin A. The maximum tolerated doses of the two types of streptococcal toxins induced approximately the same antiviral protection effect. The production curve of the antiviral factor showed a maximum at the 12th hour after incubation at 37 degrees C with graduate decrease up to the 24th hour using a 6 hours induction time. The interferons induced by the streptococcal erythrogenic toxins A and B were thermostable at 56 degrees C for 30 min and were partially destroyed at pH 2 as tested against Mengo virus in FL cells. The antiviral effect could be reversed by addition of streptococcal erythrogenic toxin A at the maximum tolerated dose simultaneously with the glycosylating inhibitors streptovirudin and D-glucosamine by 90 and 100 per cent, respectively.

Amnion↗
PubMed1981

[Osteoporosis therapy and thyroid function. Influence of 6 months of sodium fluoride treatment on thyroid function and bone density].

26 women were treated for osteoporosis with 40 mg of sodium fluoride twice a day (equivalent 36 mg of fluorine) for a longer period. Mostly by reason of incompatibility, a reduction to half of the dose was necessary in six of these patients. The control of plasma fluoride concentration indicated that only 10 patients took their medicine regularly. Before treatment as well as three and six months after beginning of treatment the patients were examined. In these examinations bone density was measured across the middle phalanx of the middle finger with a I-125-profile scanner. Size and function of the thyroid gland were evaluated by clinical aspects and with in vivo- and in vitro-methods for thyroid diagnostic. The program includes also a check up with a 12 canal-serum-autoanalyzer. In 10 patients with warranted regular intake of the drug the increase of bone density was significant after three months already. In all 26 patients a considerable increase of the alkaline phosphatase after three months was evident. Under the influence of sodium fluoride no change was seen in function and size of thyroid gland. This result verifies the efficiency of sodium fluoride in osteoporosis-therapy without any measurable influence on thyroid function.

Alkaline Phosphatase↗
PubMed1981

Interaction of streptococcal cell wall components with fibrinogen. I. adsorption of fibrinogen by immobilized T-proteins of streptococcus pyogenes.

Immobilized streptococcal T1-, T3- and T4-proteins to AH-Sepharose 4B were tested for their ability to absorb human fibrinogen. Purified fibrinogen and plasma samples were used for affinity chromatography. T1-protein was able to retain specifically fibrinogen from plasma. T4-protein bound fibrinogen in a similar manner, but it was not as specific as T1-protein. T3-protein failed to bind purified fibrinogen as well as fibrinogen from plasma. Adsorption of fibrinogen was accomplished using a 0.05 M phosphate/0.2 M NaCl/0.02% NaN3/pH 7.0 buffer system followed by elution with 0.05 M PO4/1 M NaCl/0.02% NaN3 to remove non specifically bound components. Retained components were eluted with 8 M Urea/0.025 M NaOAc, pH 5 and the fractions analyzed for fibrinogen content by SDS polyacrylamide gel electrophoresis. The presence of fibrinogen was determined by observations of the characteristic A alpha, B beta and gamma chain bands.

Adsorption↗
PubMed1981

[T-proteins of Streptococcus pyogenes. III. Communication: purification of T-proteins extracted with trypsin, pepsin and C-phage-associated lysin by means of immunochromatography (author's transl)].

T-proteins of Streptococcus pyogenes type 1 were extracted by enzymatic treatment of cells with trypsin, pepsin or C-phage-associated lysin and subsequently purified by ion exchange chromatography on DEAE cellulose as well as by immuno-adsorption on immobilized anti-T-type 1 antibodies. Immunochromatographical purified T1-proteins which were extracted by the different enzymes showed different properties in immuno-electrophoresis, SDS-electrophoresis and amino acid composition although a serological reaction of identity was found in Ouchterlony precipitation. Tryptic and peptic digestion was efficient for extraction of T protein while the extraction with C-phage-associated lysin was unsuitable for isolation of T-protein. The release of T-protein after treatment of cells with this lysin was very low and the preparation purified by this way exhibited cross-reaction with non-absorbed antisera of other types.

Bacterial Proteins↗
PubMed1981

[Isolation and characterization of erythrogenic toxins of Streptococcus pyogenes 3. communication: comparative studies of type A erythrogenic toxins (author's transl)].

The production of type A erythrogenic toxin was determined in 11 strains of Streptococcus pyogenes (serological group A). All strains produced this toxin, at quantities varying between 16 mg/l (strain "Smith") and 0.03 mg/l (strain T18). The erythrogenic toxins of 5 strains were purified by adsorption to silicate, elution, precipitation with ammonium sulfate, treatment with calcium phosphate, CM-Sepharose chromatography and gel filtration on Sephacryl S200. The preparations were found to be homogenous in SDS electrophoresis and isoelectric focusing (m.w. between 27 000 an 28 000; i.p. 52). They were serologically identical by immunodiffusion (Ouchterlony), and no spur formation was seen with crude concentrates of the toxins produced by the remainder of the strains.

Bacterial Proteins↗
PubMed1981

[Investigations about the immunobiology of m-proteins of Streptococcus pyogenes. IV. Cell-mediated immunity of rhesus monkeys (Macaca mulatta) against streptococcal antigens (author's transl)].

Cell-mediated immunity was tested in monkeys (Macaca mulatta) immunized with highly purified M-proteins by means of the lymphocyte transformation reaction. Lymphocytes from immunized and nonimmunized monkeys were stimulated with PAL-M-Proteins. IC-M-proteins were completely free of mitogenicity and no lymphocyte stimulation was to be found after immunization with 1.6 mg. Erythrogenic toxins of strain NY5 were able to stimulate lymphocytes of monkeys unspecifically.

Animals↗
PubMed1981

[Studies of the heterogeneity of streptokinases; IV. Evidence for isostreptokinases in Streptococcus pyogenes type 1 (author's transl)].

Two strains of Streptococcus pyogenes, originating from the same Griffith strain SF 130/13 but different in M protein synthesis, produce two isostreptokinases. The molecular weights of both isostreptokinases are the same (about 50 000 daltons) as well as the specific activities (38 000 and 43 000 U/mg, resp.). The activity values are influenced by an incomplete removal of ampholytes. The isoelectric points were determined as pI 6.3, and 6.5, resp. The presence of isostreptokinases was concluded by (1) the absence of proteolytic activities in the culture filtrate, (2) the same molecular weights, (3) the same specific activities, (4) the constant quantitative relation of about 1:2.5 between both isostreptokinases after refocusing, (5) a lack of cystein- or cystin residues in the molecule, (6) the appearance of both isostreptokinases in untreated culture filtrates, (7) the separability by disc electrophoresis, and (8) the lack of such double bands in streptokinases of other streptococci. Isoelectric focusing of streptokinase produced by a type 3 strain of S. pyogenes was followed by the appearance of four bands with streptokinase activity. It is unlikely that these four bands represent isostreptokinases. Both streptokinases (type 1 and type 3 streptococci) differ from streptokinases of other types by their relatively high content of tryptophane (table 1) and the high isoelectric points (6.5 to 6.0; streptokinases of other types and groups show pI's between 5.05 to 5.65 (6).

Isoelectric Point↗
PubMed1981

Purification and characterization of erythrogenic toxins. IV. Communication: mitogenic activity of erythrogenic toxin produced by Streptococcus pyogenes strain NY-5.

Some in vitro reactions involved in the mitogenic activity of a purified erythrogenic toxin from the group A streptococcus strain NY-5 (ET NY-5) were studied. The optimal dose in the human blood lymphocyte transformation test was 1 to 10(-1) microgram/ml lymphocyte culture, the maximum of 3H-thymidine incorporation was on day 3 or 4. The mitogenic activity showed the signs of nonspecificity, nevertheless, a specific mitogenic effect could not be ruled out either. When Con A and ET NY-5 were added simultaneously in high or low doses at the beginning of lymphocyte cultivation, antagonism or an additive effect was observed, respectively. Incubation of lymphocytes with ET NY-5 resulted in a decrease of mitogenic activity in the supernatants. Erythrocytes had no similar binding activity. ET NY-5 acts as a T-cell mitogen; 98% of ET NY-5-stimulated lymphoblasts formed E rosettes with sheep red blood cells. Thin-layer isoelectric focusing experiments revealed two mitogenic peaks corresponding to toxin types A and C in the ET preparation.

Bacterial Proteins↗
PubMed1981

[Influence of physical parameters on the production of streptococcal extracellular proteins in cultures with stabilized pH. I. Communication: pH-dependence of extracellular protein production (author's transl)].

The influence of the pH of the medium on growth and production of extracellular proteins was examined in a group C streptococcus (SA. equisimilis strain H 46 A). The pH values employed ranged from 5.0 to 8.5 and the analytical methods used included the determination of enzyme activities, isoelectric focusing, crossed-immunoelectrophoresis, and SDS electrophoresis. The strain is able to grow in the entire pH range used, with maximum growth occurring at pH 6.5. The amount of extracellular proteins elaborated depended on both the pH of the medium and the biomass produced. A specific pH range was defined for optimum production of all enzymes examined. With the exception of streptodornase and NAD-glycohydrolase, the pH optimum for product formation was generally in the neutral and weakly alkaline range. Active proteinase was formed only a pH 6.0, leading to gross degradation of most of the other proteins in the culture medium. At pH values ranging from 6.5 to 7.5, isoelectric focusing revealed the production of 28 different extracellular proteins, and crossed immunoelectrophoresis demonstrated 30 to 32 antigens. The number of extracellular products produced greatly declined at pH values above and below this range. Under optimum conditions, the main extracellular product at H 46 A was streptokinase, followed by deoxyribonuclease A.

Antigens, Bacterial↗
PubMed1981

[Purification and characterization of streptococcal hyaluronate lyase (author's transl)].

Hyaluronate lyase of group C strain H 46A (Streptococcus equisimilis) was purified and characterized by isoelectric focusing, sodium-dodecylsulfate-acrylamide electrophoresis, polyacrylamide-gradient-electrophoresis and crossed immunoelectrophoresis. The purification of the hyaluronate lyase was performed successively by adsorption on Florisil, chromatography on DEAE-cellulose, and - for separation of streptokinase - stirring with CPG-pore-glass. The last step was Sepharose 6B. PUrified hyaluronate lyase showed a high specific activity. The purified enzyme was found to be antigenically homogeneous. No contaminating streptococcal components could be detected. The molecular size was determined as to be 90 000 dalton by gel filtration and 110 000 dalton by sodium dodecylsulfate-acrylamide electrophoresis. The amino acid composition was also determined. In the isoelectric focusing, using gels with reducing conditions, one protein band at a pI 4.95 was observed. Under nonreducing conditions two or three diffuse protein bands which showed lower enzymatic activity were found. It might be possible that the hyaluronate lyase exists in two different forms.

Amino Acids↗
PubMed1980

[The significance of blood culture contamination in microbiological laboratories].

Blood cultures in open systems are exposed to an additional danger of contamination, when manifold subcultures are made. The blood tests of 48 patients with suspicion to sepsis were investigated in two parallel series with 6 cultures each. The blood culture flasks of one series were for the first time opened to subculture on the 10th day, those of the second series on the 3rd, 6th and 10th day. The contamination rate which was to be led back to laboratory work was in the first series nearly 1.1% (total contamination rate 2.8%), in the second series nearly 14% (and 15.8%, respectively). For blood cultures closed systems are to be recommended. If with open systems is worked, a subcultivation is to be recommended only after macroscopically visible growth or only on the 10th day.

Blood↗
PubMed1980

[T-proteins of Streptococcus pyogenes. II. Communication: Preparation of specific immunoadsorbents for isolation of anti-T-antibodies and investigations of the T4/24...pattern (author's transl)].

The T4-antigen(s) in Streptococcus pyogenes standard type strains of the T4/24...pattern was (were) investigated in regard to the uniformity or diversity of the antigen(s) in this T-complex. Tryptic T-extracts of types 4, 24, 26, 28, 29, 46, 48, 60 were purified by ion exchange chromatography on DEAE-cellulose. Anti-T4-antibodies were isolated by immunoadsorption chromatography on AH-sepharose linked T4-antigen. Purified T4-antigen showed in SDS-electrophoresis a similar multiple molecular size structure as T1-antigen described earlier. Comparative serological studies of T-antigens of types 4, 24, 29 and 46 revealed reactions of identity to anti-T4-antibodies in Ouchterlony tests. Extracts of types 26, 28, 48 and 60 did not precipitate with anti-T4-antibodies, but types 28 and 48 showed crossreaction to the relevant antisera (anti-T28 and anti-T48, resp.) obviously caused by traces of R-28 antigen in both antigen preparations. Strains of the types 4, 24, 29, 46, 48 and 60 were agglutinated by anti-T4-antibodies. The reaction could be inhibited by T4-antigen. The strains of type 26 and 28 used in our experiments did not contain T4-antigen. Agglutination as well as immunoprecipitation reactions with specific antibodies prepared by immunochromatography proved the existence of common T4-antigenic determinants in type 4, 24, 29, 46, 48 and 60.

Animals↗
PubMed1980

Antistreptococcal antibodies, rheumatoid factors and haptoglobin in apes and monkeys.

Sera of 157 baboons (Papio hamadryas and P. anubis) 21 chimpanzees (Pan troglodytes) five orang utans (Pongo pygmaeus) three mountain gorillas (Gorilla gorilla beringei) and three gibbons (Hylobates lar lar) were examined for the content of antistreptolysin O, antidesoxyribonuclease B, for the presence of rheumatoid factors as well as for the level and type of haptoglobin. The mean antistreptolysin O titer (AST) in baboons was 106 ASU +/- 18 in dextransulfate absorbed sera ("real" AST) and 182 ASU +/- 34 in non-absorbed sera. The mean decrease after absorption was 20% (i.e., 20% inhibitor + 80% antistreptolysin O), a value that is lower than previously found in rhesus monkeys (55%) or in man (40%). Raised values of anti-DNase B were found in two baboons only, and none of the sera of that species displayed presence of rheumatoid factors. In chimpanzees, the mean AST was 68 +/- 29 in absorbed and 87 ASU +/- 57 in non-absorbed sera. Anti-DNase B was raised in three animals, and in two cases the increase was correlated with raised AST. Of 19 chimpanzee sera examined, 13 were found to contain antigammaglobulins ("rheumatoid factors") the titers of which reached 1:64 or more. All primate sera tested so far showed haptoglobin type 1-1 or Hp 1-1-like patterns. The haptoglobin level in chimpanzees and baboons was comparable to that established in man; in rhesus monkey, on the other hand, much lower values (40-62 mg/100 ml) or ahaptoglobinemia were observed. The sera of all monkeys and apes tested so far showed a very low (undiluted, or up to 1:10 titer at most) agglutinating activity against T4-antigen-carrying streptococci. This is in agreement with our observations made previously which indicated that human or animal sera of haptoglobin type 1-1 agglutinated streptococci to a much lower degree than type Hp 2-2 or type Hp 2-1 sera.

Animals↗
PubMed1980

[Purification and characterization of erythrogenic toxins. I. Investigation of erythrogenic toxin A produced by Streptococcus pyogenes strain NY-5 (author's transl)].

An erythrogenic toxin was isolated from culture supernatants of Streptococcus pyogenes, strain NY-5 (type 12) grown in yeast extract-pepton-dialysate medium. After concentration by evaporation, a crude material was obtained by precipitation with ethanol. This material was prepurified by ion exchange chromatography using a DEAE-Sepharose Cl-6B column. After precipitation of the active material with (NH4)2SO4 the redissolved precipitate was dialyzed against acetate buffer and rechromatographed on a CM-Sepharose Cl-6B column. The toxin was obtained by stepwise elution with 0.02 M acetate buffer, pH 5.0, and 0.05 M phosphate buffer, pH 6.5, followed by a last purification step on a Sephacryl S-200 column. The purified toxin behaved homogenously in SDS electrophoresis, the molecular weight being about 28 000. Amino acid analysis showed only one cysteine residue per molecule. The molecule was insensitive to 2-mercaptoethanol and alkylation. Isoelectric focusing yielded two narrow bands having an isoelectric point of 5.2. The toxin showed a serological reaction of identity with an antiserum against streptococcal pyrogenic exotoxin A (SPE-A) but was shown to have a different molecular weight. The purified material (erythrogenic toxin A) was pyrogenic and toxic for rabbits as well as mitogenic for human lymphocytes. A positive skin reaction in guinea pigs could be obtained by as little as 5 X 10(-8) mg.

Amino Acids↗