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G Geserick

Publications and source records attributed to G Geserick.

17 recordsLinked to original sources

Improvement of BF typing and of BF F subtyping after neuraminidase treatment in the unconverted and converted factor B.

When neuraminidase-treated sera are analyzed by agarose gel isoelectric focusing, the factor B (BF) banding pattern is reduced to predominantly one major band without cathodically positioned bands. This not only makes unequivocal typing of BF allotypes possible but also the reliable distinction of all BF F subtype phenotypes with delimitation of "BF F subtype variants". With this new method, serum aging affects the BF determination to a lesser extent than when applying methods that separate native sera. We show that sialylation is not responsible for the BF F subtype polymorphism. All of the investigated BF allotype bands, including those characteristic of the subtypes, show functional hemolytic activity. The banding pattern after removal of neuraminic acid residues ranges from pH 6.8 to 7.3 for factor B, from pH 5.3 to 5.9 for the Ba fragment, and from pH 8.2 to 8.7 for the Bb fragment. The protein structure of factor B is also discussed. Eliminating the superimposition of bands in different BF allotypes, as demonstrated by these methods, proved to be necessary for the detection of hypomorphic BF gene products (BF QL), which are expressed by assumed BF*Q0 alleles in heterozygous genotypes. This allows investigation of BF*Q0 alleles on a protein level, which complements molecular genetic approaches.

Blood Preservation

Apparently non-expressed alleles of factor B (BF) code for hypomorphic proteins.

In three families with an apparent non-expressed factor B (BF) allele (BF*Q0), advanced methods of isoelectric focusing for the determination of BF F subtypes revealed different hypomorphic BF products (BF QL) with functional hemolytic activity expressed by the assumed BF*Q0 allele. A Taq I and a Msp I restriction fragment length polymorphism as well as the Ba fragment of the expression products showed banding patterns for the BF*QL alleles corresponding to BF S types, whereas an altered Bb fragment was seen in two BF QL products. In one family an intragenic recombination site within the Bb part of the BF gene was assumed. Investigations of factor B and its conversion fragments, as demonstrated by the used methods, allow to complement molecular genetic investigations of BF*Q0 alleles in heterozygous genotypes on a protein level. We conclude that apparently non-expressed alleles of factor B code for hypomorphic but functionally active proteins.

Alleles

[Mass disasters in former East Germany--a forensic medicine retrospect].

The authors report the analysis of mass disasters, which had been dealt with by forensic experts, on the territory of the former GDR. The report comes on the initiative of the Society of Forensic Medicine and with the support of regional institutes. For the period 1960 to 1989, 20 events with 738 casualties were registered. The number of victims was particularly high in aviation and rail disasters as well as in the Zwickau mine disaster. The Forensic Institute of the Humboldt-University in Berlin was engaged in the investigation of the three airplane crashes on Berlin territory and near Berlin (Königs-Wusterhausen 1972, Berlin-Bohnsdorf 1986 and Berlin-Schönefeld 1989) as well as of the railway disaster near Lebus in 1977. As a result of the analysis, the experience gained in three decades regarding the planning, organization and realization of the identification of victims is dealt with in more detail. It emphasizes the significance of close cooperation with dentists and criminalists. Because of ethical, legal and criminalistic reasons the aim should always be a complete examination (including autopsy) of the victims as well as their identification.

Accidents, Aviation

The development of osteosarcoma in four-fold selected group of patients.

Patients with osteosarcoma have been submitted to four-fold selection using parameters previously shown to be associated factors. These are sex, age at onset, haptoglobins and histological type. Further data have been added to the final resulting sequence of patients. In the four-fold selected group there is an age-dependent AB0 distribution which confirms the relevance of the criteria used and, consequently, the influence on sarcoma development. It can be assumed from these investigations that the occurrence of osteosarcoma is modified by several genetically fixed factors (HP type, sex, AB0 group).

ABO Blood-Group System

[Several reliable legal regulations of East German legislation in relation to the forensic medicine specialty].

The authors treat questions involving post-mortem examinations and autopsies, as regulated in the "Order Pertaining to Post-mortem Medical Examinations" in the former GDR. The administrative autopsy is of special importance in this respect. This regulation, which has been demanded by German physicians for more than a century and has existed for a long time in Austria (1857), should finally be introduced in the Federal Republic of Germany as well. It should at least be retained in the new Federal States. In the field of alcohol-related traffic law, the authors advocate a reduction of the blood-alcohol limit throughout Germany, even if the zero limit in the former GDR does not appear to be implementable. The time-tested regulations applying to organ graftings are presented as the third topic. In the GDR there was a uniform order based on the right to object.

Accidents, Traffic

Factor B reference typing report.

In a factor B (BF) Reference Typing of the VIth Complement Genetics Workshop and Conference, Mainz, FRG, 1989, 99 samples from 13 laboratories, including 18 families, were investigated with the majority of presently known typing procedures. Among the major ('standard') allotypes BF SO4 was found to be new. For the group of common BF F subtypes samples from 11 laboratories including complete family data from 5 laboratories were compared. The subtypes BF FA and FB were recognized and confirmed to be identical in the samples from all groups. Within a third group rare subtype variants of F and S were compared and characterized. In samples submitted from individuals with assumed non-expressed (BF*QO) alleles unexpected and hypomorphic gene products were seen. The investigation of DNA samples for restriction fragment length polymorphisms from the same set of individuals revealed a correlation of the Msp I 0.7-kb fragment with BF F, and confirmed the correlation of a Taq I 6.6-kb fragment with BF FA.

Alleles

Factor B (BF) nomenclature statement.

A common nomenclature for factor B (BF) allotypes is recommended as a result of the BF Reference Typing of the VIth Complement Genetics Workshop and Conference, Mainz, FRG, 1989. It has generally been agreed that the alphanumeric BF nomenclature according to Mauff et al. should also be used in the future for all major BF allotypes distinguishable by standard agarose gel electrophoresis (AGE). The common BF F subtypes and further described rarer subtype variants are not detectable by standard AGE. Therefore, the nomenclature had to be extended. For the subtypes of BF F an alphabetical designation with capital letters will now be used: FA and FB. The designation of the five rarer subtype variants was modified after the reference typing to FB1, FB2, SB1, SB2, and SB3. Hyposynthetic variants detected in samples with previously assumed non-expressed (BF*Q0) alleles are now designated as SQL, M1QL, and M2QL, HQL' characterizing their lower concentration.

Complement Factor B

Human BF*F-subtypes: segregation analysis with inclusion of MHC haplotypes.

The segregation of factor B(BF)F subtypes was analyzed in conjunction with other MHC markers in 15 families with 89 offspring. Informative data for BF F subtypes were obtained from 11 families, 6 of them with known recombinant individuals for the HLA-B/DR/GLO region. The subtypes did not contribute further to the localization of the cross-overs, but followed the known segregation of conventional BF allotypes. In 2 families of one kinship, the recognition of heterozygous BF*FAFB individuals could be established following the inclusion of three generations. The rarer of the two BF F subtype alleles, BF*FA, is positively associated with the HLA haplotypes BW62, CW3, C4A*3 and A29, CWX, B44, C4A*3, B*1, DR7. BF F subtypes are regarded as a very useful additional tool for studies of MHC organization and disease association.

Alleles

The BF F subtypes are detectable in the Ba fragment of factor B.

The unanimous recognition of the two subtypes FA and FB of the BF*F allele has repeatedly been challenged. In the present investigation we are reporting about the unequivocal and simple detection of the subtypes on the Ba fragment of factor B by immunofixation isoelectric focusing after conversion with inulin. The common BF phenotypes F, S, and FS could be diagnosed in addition to the subtypes of BF*F which were observed in two regions acidic of the F major band. By comparison of standard phenotypes the subtypes in the Ba fragment corresponded to those of native factor B. All BF bands could be attributed to the Ba fragment by developing Western Blots with monoclonal antibodies directed against Ba. The distribution of the major BF phenotypes and alleles and the BF F subtypes in a population sample of 527 unrelated individuals from F.R.G. was in Hardy-Weinberg equilibrium. The allele frequency was determined to be 0.0731 for BF*FA, and 0.1053 for BF*FB. The advantages of determining the subtypes on the Ba fragment are: broadening of the FA/FB corridor, a more reliable diagnosis of phenotypes, improved distinction between homozygous FA and heterozygous FAFB types, and recognition of common BF phenotypes as well as subtypes in aged sera. It is suggested that the problem in the designation of BF F subtypes by different groups should be resolved by an international reference typing.

Alleles

Detection of a new BF F subtype variant by isoelectric focusing.

The paper reports a new BF F variant which was observed in a family, i.e. in the father and in 2 of the 4 children. The variant can only be seen by means of isoelectric focusing and appears as an additional cathodic band of the BF subtype FB. We suggest FB1 as a preliminary name for this variant. The family studied suggested an autosomal-codominant inheritance.

Complement Factor B

[Quantitative determination of the alpha-feto-protein in the practice of perinatal medicine. 1st communication: the physiology of the alpha-feto-protein and its quantitative proof by means of electrophoresis in antibody containing gel according to Laurell (author's transl)].

The alpha-feto-protein (AFP) ist described on the basis of the available literature; its diagnostic use up to the present is outlined, and an immunological method of its quantitative determination is presented. The results obtained by quantitating the level of AFP in the cord serum of 50 mature newborns (-x = 9,9 mg/100 ml) are in good agreement with other reports.

Birth Weight

[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

[The question of the validity of haptoglobin/G-streptococci relations in nonhuman sera].

The relationship between haptoglobin type and the agglutinability of some group G streptococci, which was observed in humans, could also be demonstrated in animal sera. In humans the haptoglobin type Hp 1-1 is correlated with a lacking or very low agglutinability. Sera of 10 rhesus monkeys showed Hp-type 1-1 and agglutinated the streptococci only to dilutions of the serum up to 1:4. The sera of 48 pigs contained an Hp 1-1 like type and a streptococcus agglutination titer of max. 1:10. Seven ahaptoglobinaemic sera gave the same values. Fifty examined sera of rabbits showed also an Hp 1-1 like pattern and did not agglutinate or in undiluted state only.

Agglutination Tests

[Group-specific component imaging from trace material using isoelectric focussing and electroblotting].

GC-subtyping was carried out on blood stains, that had been made on glass and stored under room temperature-conditions. Using isoelectric focusing in polyacrylamide gel, followed by transfer to nitrocellulose membrane by semi-dry-electroblotting and detection with enzyme-linked antibody complex the GC-detection was possible even after 64 days. Methodical problems are discussed.

Blood Grouping and Crossmatching