PubMed Health⌕ Search

Biomedical subjects

W Köhler

Publications and source records attributed to W Köhler.

At least 199 records · Page 11Linked to original sources

Type-specific and non-type-specific reactions of purified M protein preparations.

M proteins of type 1 and type 12 Streptococcus pyogenes were extracted by means of phage-associated lysin and purified by ion-exchange chromatography on CM and DEAE cellulose. Molecular weight distributions were studied by gel chromatography on Biogel A 0.5 m in a 6 molar urea solution and by SDS electrophresis. Serological activities were studied by the complement-fixation reaction and immunodiffusion and were compared with the estimated molecular weights. Type-specific and non-specific activity was found to be located on the same polypeptide chain of a size of 2 X 10(4) daltons (type 1) and 1.5 X 10(4) daltons (type 12). These serologically active chains are in preparations purified by chromatographic methods accompanied by polypeptides of different sizes which are held together by noncovalent bonds thus forming molecules above 4 X 10(4) daltons.

Bacterial Proteins↗

[Influence of the mode of collection on the result of blood cultures].

In a prospective study of 133 patients with suspicion of a septic process the influence of the withdrawal modus on the bacteriologic result was examined using an open blood culture system. For patients without pretreatment with antibiotics or without high temperature the "one time" withdrawal of the blood culture should be preferred to the "multi-time" method. A multi-time withdrawal showed similar and better evidence quotas with patients without fever and under influence of antibiotics. The result depends on the number of blood cultures for each patient. If there is presupposed a minimum of 2 positive blood cultures for each patient as indication of a septic process, a 83 per cent indication quota is attained with 12 one-time blood cultures, a 70 per cent indication quota with 8 blood cultures, and a 53 per cent indication quota with 4 blood cultures. In multi-time withdrawal the comparable indication quotas are 55, 45 resp. 32 per cent.

Anti-Bacterial Agents↗

[Relationship between anti-G-streptococcal titers and the haptoglobin type in human serum--aspects of the observed correlations].

In systematic investigations we found a relationship between the haptoglobin types of human sera and the agglutinability of some group-G streptococcal strains. Sera with the haptoglobin type Hp 1-1 do not agglutinate these strains (or with low titres up to 1:16 only). On the other hand sera with the haptoglobin types Hp 2-1 or Hp 2-2 agglutinate the streptococci with titres from 1:200 to 1:3,200 (or more). The aspects resulting from these findings were discussed in detail. They may have among others practical consequences for the forensic medicine and the role of the haptoglobins must be thought over again.

Antibodies, Bacterial↗

[A photometric method for the diagnosis of pregnancy in blood stains by determination of heat-stable alkaline phosphatase (EC 3.1.3.1). A modification of Oya, Asano and Fuwa's technique (author's transl)].

A quantitative method, described by Oya and coworkers was modified. In this way, venous blood from pregnant and nonpregnant women in blood stains can be reliably differentiated up to at least 19 months storage although as a qualitative test only. 1--3 cm2 of cloth stained with blood is needed and even less from placental blood stains.

Alkalies↗

Increase of the corticosterone level in ducklings during the sensitive period of the following response.

Increased fear may be one of the factors limiting the sensitive imprinting period. Thus, we analyzed corticosterone levels in 121 Peking ducklings during and after this sensitive period using the method of competitive protein binding. The data pointed to a corticosterone increase within a period of 12-28 hr after hatching as well as to the presence of a circadian rythm. The low coefficient of determination of post-hatch age and corticosterone level (8%) pleads for a multi-dimensional system. However, the corticosterone increase may be the basis for an increase in fear and a decrease in the likelihood of imprinting.

Age Factors↗

[The occurrence of cross-reactive antigens in myocardial tissue and in streptococcus pyogenes. IV. Cytotoxic effect of lymphocytes sensitized in vivo to group A streptococci on primary cultures of heart muscle cells (author's transl)].

The cytotoxic effect of rat lymphocytes in vivo sensitized to group A streptococci, rat heart tissue or streptococcal M proteins was investigated in primary cultures of beating rat heart cells. Cytotoxicity was found in 75 to 82% of heart cell cultures in contact with lymphocytes sensitized to streptococcal whole cells or lysates and in 100% of those exposed to lymphocytes sensitized to rat heart tissue. Lymphocytes sensitized to M protein exert a cytopathic effect only in 8 and 12% cultures, respectively, and to a much more limited extent. Controls were affected in 6%. The cytotoxicity test seems to be useful to examine the presence of cross-reactive antigens within streptococcal vaccines.

Animals↗

[Role of B streptococci in perinatal medicine].

Vaginal swabs from 1140 women were investigated for presence of group B-streptococci. In nonpregnant women the carriage rate was 3.3%. During the pregnancy the highest colonisation rate was in the second trimenon. The serotypes were distributed approxmiately the same in both groups of patients, with the exception of types III and R. All strains were sensitive against ampicillin and lincomycin, in 6 cases we found a reduced sensitivity against penicillin. These results are compared with those from other authors and discussed in regard to sepsis and meningitis of the newborn.

Anti-Bacterial Agents↗

[Studies of the heterogeneity of streptokinases of different origin (author's transl)].

Streptokinases of six different strains of group A streptococci (Strep. pyogenes), and of one strain each of streptococcal groups C and G were isolated from supernatants of the cultures. The purified or partial purified streptokinases were characterized by electrophoresis in agar-acrylamidgels, isoelectric focussing in acrylamide gel and by determinations of the molecular weights by means of sodium dodecylsulphate acrylamide electrophoresis and gel filtration on sephadex G-100. Furtheron these streptokinases were compared serologically using human antistreptokinase-antiserum. It was found that all of the streptokinases examined in this study were different in their isoelectric points (5.05-6.5) and that they showed serological cross-reactions. The molecular weights are not significantly different and were determined to about 45 000 daltons.

Cross Reactions↗

[Human haptoglobin type and G-streptococci: a safe and unexpected relation].

By testing 167 human sera a surprising dimorphism could be found. All sera of the haptoglobin type hp 1-1 belong to the group with an anti-G streptococci titer in the range of 1:0 to 1:10 whereas sera of the types hp 2-1 and hp 2-2 do have titers in the range between 1:200 and 1:3200 or more. All tests are carried out in the double blind technique.

ABO Blood-Group System↗

[Secretory antibodies in saliva against group G streptococci (author's transl)].

Saliva of 310 persons were examined for their ability to agglutinate 33 streptococcal strains of the groups A-T. It was found that the saliva of persons with blood group O agglutinated significantly more often streptococci of strain G9 than the saliva of persons with blood group A (33.3%, and 18.75% resp., p less than 0.01). A statistical significant difference between persons of blood group B and O, or A and B did not exist. The agglutination reactions were caused probably by unspecific immunoglobulins because this strain G9 binds unspecifically human IgG. It is known, that some streptococcal strains of the groups A, B, C, D, and G contain receptors for the Fc-fragment of IgG and/or IgA. The results demonstrate that persons of the blood group O secrete more often immunoglobulin than those with blood group A.

Agglutination Tests↗

[Relationship between haptoglobin types and group G streptococci (author's transl)].

A relationship was found between the haptoglobin types of human sera and the agglutinability of some strains of group G streptococci. Sera with the haptoglobin types Hp 2-2 and Hp 2-1 agglutinate these streptococci to high titers, from 1:200 up to more than 1:6400. On the other hand, the sera with haptoglobin type Hp 1-1 agglutinate not more than up to titers of 1:16 (mostly lower). Out of 102 strains of group G streptococci only 3 showed this characteristic phenomenon. This study was undertaken in order to elucidate whether the Hp 2-2 and Hp 2-1 proteins have antibody activity. Incubation of Hp 2-2 or Hp 2-1 sera with antihaptoglobin antisera or with anti-Hp 2-antiserum did not change the agglutinating activity but the haptoglobin was eliminated from the sera. Absorption of Hp 2-2 and Hp 2-1 sera with these group G streptococci lowered the titers significantly but the haptoglobins are detectable as in the non-absorbed sera. Sera with haptoglobin 1-1 contain an inhibitor. Mixing of Hp 2-2 and Hp 2-1 sera with high agglutinating titers with Hp 1-1 sera (low titers) was followed by a significant decrease of the titer.

Agglutination↗

[Demonstration of an agglutination-like nature of haptoglobins against streptococci with T4-antigen through the examination of umbilical cord sera].

The determinability of haptoglobin types is correlated with the titers of agglutination against streptococci carrying the T4 antigen. If the haptoglobin types in cord-sera cannot be determined (as a result of the physiological binding of haptoglobins) the agglutination reaction fails or the titers are greatly diminished. The dimorphism, which was found in sera of adults, can be demonstrated in cord sera, too, if they can be typed. It is concluded that the observed reaction between Hp 2-2 and Hp 2-1 sera with T4-streptococci is caused by the haptoglobin itself.

Agglutination↗

[Relationships between Streptococcus pyogenes T4-antigens and haptoglobin types (author's transl)].

Some strains of beta-haemolytic streptococci were agglutinated with high titers (1:200-1:6400) by human sera of the haptoglobin types 2-2 and 2-1. No agglutination or with low titers (up to 1:20) was observed with sera of the haptoglobin type 1-1. This reactivity depends from the contents of Streptococcus pyogenes T-antigens of the T-complex 4,24... This T4-antigen is present in group A streptococci (Strep. pyogenes) of the types 4, 24, 26, 28, 29, 46, 48 and 60 but it may be present also in some strains of streptococcal groups C and G. During a 10-year period we isolated 12 strains of Strep. equisimilis (group C) carrying the T-4 antigen (1.6%) and 50 group-G streptococci with T-4 antigen (6.4%) of all group G streptococci). These strains were agglutinated without an exception with high titers by Hp 2-2 and Hp 2-1 sera but not by sera of the haptoglobin type 1-1. The same particuliarity was shown by Streptococcus pyogenes types of the T-complex 4, 24... One strain of type 26 (BC 179) has no T antigen and therefore it was not agglutinated in the above mentioned manner. The phenomenon depends from the medium; it occurs after cultivation of the streptococci in Pope broth or in meat-infusion with glucose but not or only reduced in beef heart-proteose-medium. The agglutination reaction is caused by the haptoglobin but not by agglutinins against the T4-antigens.

Agglutination↗