Biomedical subjects

B Brinkmann

Publications and source records attributed to B Brinkmann.

At least 19 recordsLinked to original sources

PubMed1992

Population genetics and forensic efficiency data of 4 AMPFLP's.

Family studies were carried out in a population sample from north west Germany using 4 amplifiable VNTR polymorphic systems D1S80 (MCT118), ApoB, D17S30 (YNZ22) and COL2A1. Separation was carried out in polyacrylamide gels and visualised using silver staining. In family studies (n = 30) no evidence of new mutations was found. The population study of unrelated individuals (mothers and putative fathers) showed that all 4 systems were highly polymorphic and similar to other population studies. The combined exclusion chance was calculated to be approximately 99% and the combined discrimination index 1.5.10(-4). The Hardy-Weinberg equilibrium was checked by forming groups of alleles and no significant deviations could be found in all systems.

Alleles↗

PubMed1992

Some technical parameters influencing the precision and accuracy of fragment size determination for RFLP's.

A comparison was carried out between 3 computer-assisted systems for the estimation of DNA fragment length: (1) the "Digitab" system (developed at our institute), (2) the FBI analysis system (FBI Quantico, USA) and (3) the BioImage system (Waters/Millipore, USA). Both the FBI system and the BioImage system were found to be much more precise than the manual Digitab system. In an additional experiment, a possible influence of the field strength on the "accuracy" of fragment size measurement was checked. Lowering the field strength to approx. 1V/cm led to a statistically significant increase in the measured fragment size.

Computer Systems↗

PubMed1992

Forensic identification of urine samples.

VNTR polymorphisms were investigated for the possible individualisation of human urine samples with reference to doping cases in sport. Investigations were carried out with the RFLP single locus system YNH24/Hinf I and the PCR-VNTR systems Apo B and COL2A1 (AMPFLPs) as well as SE 33 and TC 11 (STRs). Urine samples were tested using 3 different volumes (10 ml, 1 ml and 0.1 ml) after 2 days and 2-5 weeks storage at 4 degrees C. Positive results were obtained for STR systems in all cases and with the smallest volume of urine tested (0.1 ml). The AMPFLP systems gave positive results in 4 out of 8 (Apo B) and 5 out of 8 (COL2A1) samples and YNH24 was successful in 1 out of 3 samples. Negative results were obtained for the AMPFLP systems and YNH24 after longer storage periods whereas the STRs were positive.

DNA↗

PubMed1992

pMCT 118 (D1S80): a new allelic ladder and an improved electrophoretic separation lead to the demonstration of 28 alleles.

Population data studies carried out on caucasians from Northwest Germany (n = 218) using the AMPFLP system pMCT 118 (D1S80). The method used in a previous study (Rand et al. 1992) for pMCT 118 could be improved by increasing the electrophoretic separation length from 10 to 20 cm and by using an extended allelic ladder which allowed the distinction of 8 additional alleles (a total of 28 alleles). Out of the 8 additional alleles 5 could be differentiated which differed within the 16 bp repeat sequence. The allele frequencies found were compared to population data from American caucasians, Hispanics and black Americans (Eisenberg and Maha 1991). All populations with the exception or black Americans, showed good agreement.

Alleles↗

PubMed1992

Optimized amplification of the polymorphic system COL2A1.

The influence of various amplification parameters on the demonstration of COL2A1 patterns was examined in serial experiments. The combination of 6 optimized parameters (concentration of primers, nucleotides, Taq polymerase, K+, Mg2+, number of cycles) led to an approximately tenfold increase in sensitivity and a decrease in allelic drop-out. In unequal mixtures of DNA from 2 individuals the weakest component was detectable in dilutions down to 1:20. In a small population sample (n = 120) 10 alleles could be demonstrated.

Electrophoresis, Polyacrylamide Gel↗

PubMed1992

ABH-related antigens in human male genital tract. A histochemical examination.

The localization of ABH related antigens in human male reproductive tract was examined using monoclonal antibodies and an avidin biotin complex method. No positive reaction with blood group antibodies on spermatozoa was observed in testis and ductus epididymidis apart from erythrocytes and endothelial cells. The expression of ABH and ABH related antigens in ductuli efferents testis, ductus epididymidis, seminal vesicle and prostate was complexly coded by a combination of H, Se, Le and X genes. The results obtained in this study indicate that the ABH antigens detected on spermatozoa of seminal stains are coating antigens and not inherent to the cell membrane, and the ABO, H, Se, Le and X genes are subjected to a tissue-dependent differential expression.

ABO Blood-Group System↗

PubMed1992

Evaluation of sperm specific lactate dehydrogenase isoenzyme C4 (LDH C4)--application to semen detection in stains.

The usefulness of LDH C (or LDH X) as a semen-specific marker has been tested. Many different methods have been applied for identification using various electrophoretic methods such as agarose gel electrophoresis, IEF, rocket-immunoelectrophoresis with subsequent enzymatical, immunological and immunochemical detection methods. Further methods applied were dot blot analysis for LDH C and PCR analysis for X/Y-chromosome differentiation. In blood/semen mixtures the LDH C-bands were detectable in dilutions up to 50-fold after staining for total LDH activity. An appropriate extraction procedure was developed. Immunological tests using a polyclonal antibody against LDH C were found to be highly specific and highly sensitive. The immunological test gave positive results with azoospermic stains up to a few weeks and in normal sperm stains positive reactions were obtained even after 8 months storage. A comparison of different detection methods for semen showed that immunological detection methods for LDH C are, at least after longer time periods of storage, superior to microscopical detection. Swabs showed positive LDH C-reactions up to 48 h after intercourse. This reaction was closely correlated to PCR for male cells and to microscopical searching.

Electrophoresis, Agar Gel↗

PubMed1992

A report of an international collaborative experiment to demonstrate the uniformity obtainable using DNA profiling techniques.

This paper describes a collaborative exercise intended to demonstrate whether uniformity of DNA profile results could be achieved between different European laboratories. It was shown that this goal can be obtained provided that a common protocol is followed (specifically the use of a common electrophoretic buffer as being the most important parameter). Generally, lower molecular weight loci (with lower molecular weight fragments) such as YNH24 perform better than higher molecular weight loci such as MS43a. The results of the exercise are discussed in relation to the objectives of the European DNA profiling group (EDNAP).

Autoradiography↗

PubMed1992

Pathological approaches to SIDS. I. Special emphasis on the histopathological differences between SIDS and asphyxia.

Histopathological observation was performed to clarify pathological differences of the lung between SIDS and asphyxia. In regard to pulmonary edema, there was no significant difference between SIDS and asphyxia. Occurrences of microemboli in the pulmonary vessels in cases of SIDS showing aspiration of gastric content into the lung, asphyxia and drowning were significantly high, compared with that of SIDS cases without aspiration.

Adolescent↗

PubMed1991

DNA investigations on fetal material from paternity cases.

Three paternity cases have been investigated where DNA was extracted from fetuses (age: 8-10 weeks old) after interruption of pregnancy. In each case it was possible to clearly identify the putative father using 5 or 6 single locus probes (SLP's). Fetal bands (SLP) could be clearly identified from mixtures of placental and fetal DNA by comparison with the maternal and paternal bands. However, it was very difficult to resolve the fragment patterns of tissue mixtures with one multi locus probe (MLP), because of band overlap. Another advantage of using SLP's was that biostatistical calculations could be carried out and very informative Essen-Möller values for the probability of paternity were obtained.

Abortion, Therapeutic↗

PubMed1991

Problems associated with the DNA analysis of stains.

Selected stain cases are presented which highlight various problems associated with DNA investigations on stain materials, especially risks of artefacts. These cases involve stain materials (blood, semen) which were exposed to different external conditions so that the DNA was partially degraded and of variable quantity. One multi locus probe (MLP) and 4-6 single locus probes (SLP's) were used for individualisation but artefacts such as extra bands, band deficiencies or shifts only occurred with the MLP. In one case where only a few spermatozoa were present in the vaginal swab, DNA extraction was carried out without preferential lysis to avoid loss of sperm DNA. The resulting mixed band pattern could be clearly attributed to the bands from the corresponding blood samples after SLP hybridisation.

Artifacts↗

PubMed1991

Detection of foreign particles in traumatized skin.

The aims of the medico-legal investigation of wounds are a description of the wound morphology, the characterization of the force used and finally identification of the weapon. The demonstration of foreign particles, such as wood particles, paint fragments, synthetic materials, sand or gravel particles, powder residues and rust particles, in the depth of a wound or in the surrounding area can be of great value. In the present series of experiments the suitability of imaging methods (low energy X-ray imaging, direct X-ray magnification, nuclear magnetic resonance) for the detection of relevant foreign particles has been investigated.

Foreign Bodies↗

PubMed1991

Immunohistochemical investigations to demonstrate vital direct traumatic damage of skeletal muscle.

The muscle proteins actin, myosin, desmin and myoglobin were investigated in traumatically damaged human and animal skeletal muscle using an immunohistochemical PAP-method. A depletion of all the proteins investigated was observed in muscle fibres damaged in the antemortem period. The antigens could however also be demonstrated in the otherwise empty sarcolemma, the discoid disintegration zones of the fibres and between the fibres. The depletion begins immediately after the trauma and myoglobin is the first to be affected. No such changes could be observed after post mortem muscle damage. The antigens could be demonstrated until 72 hours post mortem. The demonstration of protein depletion is an important addition to the light microscopical findings in vital muscle alterations.

Actins↗

PubMed1991

Population and family data of RFLP's using selected single- and multi-locus systems.

The multi-locus systems (MLS) 33.15 and 33.6 (Jeffreys et al 1985a) and the single-locus systems (SLS) MS 1, MS 8, MS 31 and MS 43 (Wong et al. 1987) were investigated. The number of bands and the rate of band sharing were determined for both multi-locus systems and compared to the results of an English survey. Additionally 73 families were investigated using the multi-locus probes and the results compared to those obtained for the traditional blood grouping systems. The results were in full agreement so that no evidence of new mutations could be found. The fragment distribution was calculated for each of the 4 single-locus systems and compared to the values reported in an English survey (Smith et al. 1990b). Distinct discrepancies were seen in the systems MS 1 and MS 8. Family analyses were carried out for the 4 single-locus systems and compared to English data (Jeffreys et al. 1988) to look for any indications of possible new mutations. Only one isolated exclusion could be demonstrated with MS 1.

Chromosome Mapping↗

PubMed1991

Diethylene glycol (DEG)-associated myocardial changes: a pilot investigation of chronic intoxication in guinea-pigs.

The myocardium of guinea pigs fed on sublethal doses of diethylene glycol (DEG) over a period of 2-11 days was examined for microscopical and ultrastructural changes. Coagulative myocytolysis and loss of myofibrils, not observed in the controls, was patchily distributed throughout the myocardium. The accompanying ultrastructural features included swelling, pleomorphism and hyperplasia of mitochondria with an associated distension of the interfibrillary spaces and a displacement, distortion and rupture of adjacent myofibrils.

Administration, Oral↗

PubMed1991

Paternity testing--quo vadis?

The basis and efficiency of paternity testing using conventional markers (alloantigens or electrophoretically defined polymorphisms in blood) for individuals involved in cases of affiliation are shown. A possible use of DNA polymorphisms in paternity cases is discussed. Due to the fact that the formal genetics of DNA polymorphisms have not been fully validated by the analysis of large numbers of informative meioses, it is not yet possible to include these systems in routine paternity testing. As the vast majority of cases can be resolved by conventional markers, the inclusion of DNA polymorphisms is not usually necessary; in some cases, however, they can provide additional information.

DNA Fingerprinting↗

PubMed1991

[Direct radiographic magnification in forensic medicine].

The aims in medico-legal investigation of wounds are description of the wound morphology, the characterization of force applied and the identification of the weapon used. The detection of foreign bodies (paint fragments, glass particles, sand or gravel particles, rust particles and powder residues) in or around the wound can be of great value. The suitability of X-ray magnification for the detection of such foreign bodies was investigated in the present study. Other possible applications of this method in forensic practice are discussed.

Foreign Bodies↗

PubMed1990

[Ultrastructural pathology of mechanical skeletal muscle damage].

In continuation of previous light microscope investigations the question has been raised whether the criteria determined for vital muscle damage using light microscopy, could be verified and perhaps extended for the ultrastructural region. In addition to existing human pathological material taken early post mortem, muscle tissue obtained from animal experiments was also examined. The evaluation concentrated on the muscle cells, the cell organelles and the contractile apparatus. An evaluation of semi-thin-sections was carried out in parallel. The following reaction patterns could be defined as vital reactions: hypercontraction bands, zones of rupture in narrow topological relationship to organelle changes, microstructure changes with disintegration of the fibre structure, subsarcolemmic and interfibrillary oedema, decomposition of the sarcolemma. The earliest vital reactions were detectable after only a few minutes survival time. The comparison between the results of animal experiments and human pathology and the application of the results to forensic pathology will be discussed.

Animals↗