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G Geserick

Publications and source records attributed to G Geserick.

At least 37 records · Page 2Linked to original sources
PubMed1998

Reference typing report for complement factor B.

Factor B (BF) reference typing was carried out on the occasion of the VIIth Complement Genetics Workshop in Mainz, May 1998. Two different sets of samples were analysed by agarose electrophoresis and/or isoelectric focusing at the protein level, and by PCR-RFLP analysis at the DNA level. These results confirmed the reliability of the standard agarose electrophoresis technique for the identification of the major BF alleles as well as for the identification of cathodic and anodic variants. However, the exact alphanumeric designation of individual variants relative to the reference distance between alleles S and F1 turned out to be more difficult. Using PCR-RFLP analysis, the common alleles F and S as well as the FA and FB subtypes in 6 samples containing an F allele were all assigned correctly. However, the variants F1 and S07 were not detected by this method, as they could not be distinguished from the accompanying S allele. Therefore, a combined application of all three typing methods is recommended for a reliable identification of factor B alleles, variants and FA/FB subtypes.

Alleles↗
PubMed1998

Reference typing report for complement component C3.

A comparison of five C3 variant samples has been performed by conventional high-voltage gel electrophoresis in three laboratories (Palermo, Berlin and Mainz). Local designation was shown within SD = +/-0.75 mm migration distance in the Mainz laboratory. Methodological modifications by laboratories were not accounted for (cooling temperature, relative mobilities between runs). In parallel, all reference samples were also sequenced after exon-specific amplification. As a result, two variants with identical final designations and two variants with different mobilities were shown to conform at the molecular basis exhibiting an amino acid exchange that causes the corresponding change in relative mobility as compared to normal C3F and C3S.

Blood Protein Electrophoresis↗
PubMed1998

Reference typing report for complement component C6: protein typing.

Within the C6/C7/C9 Session of the VIIth Complement Genetics Workshop and Conference, various C6 protein allotypes collected from four laboratories were examined using polyacrylamide gel isoelectric focusing (PAGIF) followed by direct immunofixation. Nineteen different variants including 17 recognized allotypes and introducing two new allotypes were distinguished besides the two common allotypes C6 A and C6 B. They were designated basically according to the previous statement on C6 nomenclature. Details on C6 DNA markers and associations of C6 markers with deficiencies of terminal complement components are published in the preceding paper of this issue.

Complement C6↗
PubMed1996

Phenotype change in polymorphic plasma proteins following liver transplantation.

In 7 patients who received liver transplants, 12 plasma proteins were subjected to phenotype analysis in donor and recipient before and after transplantation. The plasma proteins analyzed were haptoglobin, transferrin, glycoprotein GC, alpha-1-antitrypsin, complement factor 3 (C3), orosomucoid 1, properdin factor B, complement factor 6, alpha-2-HS-glycoprotein (A2HS), plasminogen, factor B of coagulation factor XIII, and interalpha-trypsin-inhibitor (ITI). Classification was done with isoelectric focusing or agarose gel electrophoresis (C3). A change from recipient to donor type was observed for all systems with the exception of C3. This is the first time such data have been obtained for the A2HS and ITI systems. The time is indicated at which the recipient type disappeared and the donor type appeared. In addition to the expected phenotype changes from recipient to donor type, unexpected results were found in some systems. For instance, in 2 patients a mixed type was synthesized, or new phenotypes appeared. Possible explanations include blood transfusions, immunosuppressive therapy, extrahepatic sites of synthesis and disturbed transplant function. The usefulness of phenotype determination as a diagnostic criterion for transplant function is discussed.

Adult↗
PubMed1995

Simple detection of the inter-alpha-trypsin-inhibitor (ITI) polymorphism by isoelectric focusing with direct immunofixation.

The inter-alpha-trypsin inhibitor (ITI) polymorphism was analysed in a German population, using polyacrylamide gel isoelectric focusing with subsequent direct immunofixation with monospecific ITI antisera. Gene frequencies of ITI*1, ITI*2, ITI*3, and ITI*4 were calculated to be 0.6150, 0.3753, 0.0078 and 0.0019, respectively. In our study the allele ITI*4 is described for the first time in a German population.

Alleles↗
PubMed1994

Genomic analysis of the F subtypes of human complement factor B.

Factor B of human complement is encoded within the Major Histocompatibility Complex (MHC) and is polymorphic, with up to 30 alleles defined by electrophoretic mobility. One of the most common alleles, BF*F, is subdivided into the FA and FB subtypes, which differ at the gene level by non-synonymous base substitutions in the seventh codon. We have found at this position a new restriction site polymorphism, as a Bsl I site absent from the FB allele. Using this restriction polymorphism, we have developed a method for BF F subtype determination, based on amplification by polymerase chain reaction of the 5' end of the BF gene, and digestion with Bsl I. This new method has been applied to a panel of 29 selected BF F individuals. A single strand DNA conformation analysis of the same region of the gene allowed us to confirm the above DNA-based BF F subtyping. During this study, two BF*F1 alleles showed discrepancies between protein and DNA typing, which were confirmed by our sequencing data. These were identical, in the 5' region, to BF*S and BF*FB genes, respectively. In a comparison with two protein subtyping methods, identical results were found for only one third of the selected samples. The conflicting results may arise, in part, from previously undescribed molecular heterogeneity within BF F subtypes, or from the presence of a null allele. Our new method allows BF*F subtyping to be used with confidence in the definition of disease-associated MHC haplotypes.

Alleles↗
PubMed1992

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↗
PubMed1992

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↗
PubMed1992

[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↗
PubMed1991

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↗
PubMed1991

[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↗
PubMed1990

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↗
PubMed1990

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↗
PubMed1989

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↗
PubMed1989

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↗
PubMed1989

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↗
PubMed1988

The genetic haptoglobin polymorphism: relevance of paternity assessment.

A practical method for haptoglobin subtyping is described utilizing fast sample preparation by means of batch adsorption to DEAE-cellulose and subsequent isoelectric focusing of reductively cleaved samples. The expanded haptoglobin polymorphism leads to an increase of the theoretical paternity exclusion rate to approximately 33%. Hence, the system appears to be highly attractive for paternity assessment.

Haptoglobins↗