Biomedical subjects

B Brinkmann

Publications and source records attributed to B Brinkmann.

At least 199 records · Page 11Linked to original sources

PubMed1993

Forensic validation of the STR systems SE 33 and TC 11.

Population studies on Caucasians from northwest Germany were carried out using the short tandem repeat (STR) systems SE 33 (Locus: ACTBP2) and TC 11 (Locus: 11p15.5). After electrophoresis in PAG 26 alleles could be identified for SE 33 in a sample size of 180 unrelated individuals and 6 alleles were found for TC 11 in 110 individuals. The combined mean exclusion chance for both systems was 0.96 and the discrimination index 0.999. No significant deviations from Hardy-Weinberg equilibrium could be demonstrated. In a small sample of families (SE 33 - n = 21; TC 11 - n = 30) no new mutations could be found. Positive and reproducible results for both STRs could be obtained from 50 pg template DNA.

Alleles↗

PubMed1993

DNA typing of debris from fingernails.

In 3 series paired volunteers were asked to gently scratch each other with the fingernails to produce superficial abrasions only of the stratum corneum. In a 4th series scratch marks were produced in the skin of cadavers but additionally including the deeper epidermal layers. Debris was removed using a thorough technique in series 1 and 2 and a careful technique in series 3. After DNA extraction, the debris was typed using the STR systems HUMACTBP2 (SE33), HUMTH01 (TC11) and HUMVWFA31 (VWA). In the material obtained from series 1 (i.e. scratching with no prior cleaning of the nails) and series 2 (i.e. cleaning of the nails prior to the experiment) the debris was removed with a sharp instrument and only the DNA pattern of the person who carried out the scratching could be detected. In the 3rd series extraneous material was removed very carefully from under the fingernails to avoid contamination with DNA from the nails. In 71% of these cases DNA patterns of the person who had been scratched or mixed DNA patterns of both persons could be detected. In the experiments with postmortem skin the DNA pattern of the cadaver could be detected in all cases. These results show that in crime cases where the perpetrator has been scratched by the victim, sufficient material can be obtained from under the fingernails for DNA typing if removal of the particles is carried out with sufficient care.

DNA↗

PubMed1993

Sudden death due to cardiac sarcoidosis in a case of suspected homicide.

In a case of suspected homicide death due to natural causes--cardiac death (SCD)--was found at autopsy. Despite an extensive replacement of myocardial tissue by sarcoid granulomata there was no history of cardiac dysfunction or preceding symptoms. The transmurally infiltrating granulomata and the concomitant fibrosis were predominantly confluent. They occupied vast areas within the interventricular septum and the adjacent posterior wall of the left ventricle. The only other organs involved were mediastinal lymph nodes, which appeared macroscopically normal.

Adult↗

PubMed1993

The application of selected histochemical and immunohistochemical markers and procedures to the diagnosis of early myocardial damage.

Histochemical (= HIS) methods (haematoxylin-eosin, luxol fast blue, chromotrope aniline blue) and various immunohistochemical (= IH) markers (myoglobin, desmin, fibrinogen, complement C5b-9) were applied in parallel to test the efficiency, specificity and sensitivity for the recognition of early ischemic myocardial damage. The whole series was subgrouped into cardiac deaths (N = 35) and controls (N = 13). Cardiac deaths were sub-divided into 3 groups: 1. infarction visible in gross examination (N = 15), 2. coronary thrombosis without infarction (N = 11), 3. stenosing coronary atherosclerosis without infarction (N = 9). The control group (group 4) consisted of unnatural deaths with presumed short agonal periods (N = 13). Group 1 cases usually exhibited extended coagulation necrosis of the diffuse type and the contraction type in combination (1 exception). Group 2 showed mainly a patchy type of coagulation necrosis and contained 1 cases where all methods failed to react and 3 more cases where only the HIS methods failed to react. Group 3 and 4 were associated with a disseminated type of single and/or grouped fibre necrosis. In addition, the average reaction strengths showed a decrease from group 1 to group 4 which was more pronounced in the HIS reactions compared with the IH reactions. One case in group 1 showing negative IH reactions cannot be explained. Positive IH reactions observed in a few cases in group 2 contrasting with negative HIS reactions would indicate a greater sensitivity of this methodology and this interpretation also applies to groups 3 and 4. From pathophysiological considerations, the positive cases in groups 3 and 4 can be well explained.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

Immunohistochemical alterations after muscle trauma.

The proteins fibrin, fibrinogen, fibronectin and complement C5b-9 were investigated in mechanically damaged skeletal muscle. An accumulation of fibrin, fibrinogen and fibronectin could be observed immediately after intra-vital trauma in damaged fibre zones, later an accumulation at the torn edges of the fibres. The accumulation of complement C5b-9 began one hour after trauma. After post mortem trauma no positive reactions could be observed for any of the proteins. The degree of expression of these proteins can therefore be used to differentiate between vital and postmortem muscle damage as well as the estimation of wound age in the early antemortem time period.

Animals↗

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↗