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Biomedical subjects

B Brinkmann

Publications and source records attributed to B Brinkmann.

At least 91 records · Page 5Linked to original sources
PubMed2001

Pentanucleotide short tandem repeat locus DXYS156 displays different patterns of variations in human populations.

AIM: To establish a database for the pentameric short tandem repeat locus DXYS156 from worldwide populations for routine genotyping in forensic identity testing and evolutionary biology. METHODS: Using polymerase chain reaction with a newly designed primer pair, we analyzed 1,408 male and female samples from 28 populations representing four major geographic groups. RESULTS: We observed 11 different alleles, which we sequenced and used to construct an allelic ladder. CONCLUSION: DXYS156 displays a contrasting pattern of X-linked and Y-linked variation among geographic regions, and between X and Y chromosomes. This complex allele distribution may be forensically useful for the ethnic differentiation of unknown stains.

Alleles↗
PubMed2000

Multiple interchanging of tissue samples in cases of breast cancer.

Due to the suspicion of a gynaecologist, a pathologist was suspected of incorrect diagnoses in cases of breast cancer and the interchanging of tissue samples. Many women applied to the attorney's bureau to clarify the reproaches. The privately owned laboratory for pathology was searched and 926 histological slides, roughly the same number of paraffin blocks and about 20 formalin fixed tissue samples were confiscated. Together with other confiscated material, at least 1236 histological slides and additional 249 paraffin blocks had to be sorted. Histological slides and paraffin blocks were matched with patients as far as possible following the laboratory book. Many of the warranted samples which were diagnosed as containing the carcinoma by the pathologist were missing. A total of 160 samples were chosen and rediagnosed by two independent pathologists. The formalin fixed tissue was negative for DNA most likely due to storage in formalin for years. Most of the histological slides were positive for DNA. On the whole, 18 expertises about histological findings and the DNA results were given. In some cases only DNA results could be presented, as previous experts had only performed DNA examinations without controlling the histological diagnosis. In six cases a carcinoma could be confirmed and the DNA profile matched with patient's DNA; in seven cases a carcinoma was confirmed without match with the patient; in two cases the carcinoma could not be confirmed in the presented samples. A jurisdictional solution was impossible because the accused pathologist died during the investigation. In conclusion, it must be stated that a DNA examination of histological slides should never be performed without a rediagnosis of an independent pathologist and photographic documentation of the findings. Whenever possible, material should be left on the slide.

Biopsy↗
PubMed2000

A short tandem repeat-based phylogeny for the human Y chromosome.

Human Y-chromosomal short tandem repeat (STR) data provide a potential model system for the understanding of autosomal STR mutations in humans and other species. Yet, the reconstruction of STR evolution is rarely attempted, because of the absence of an appropriate methodology. We here develop and validate a phylogenetic-network approach. We have typed 256 Y chromosomes of indigenous descent from Africa, Asia, Europe, Australia, and highland Papua New Guinea, for the STR loci DYS19, DXYS156Y, DYS389, DYS390, DYS392, and DYS393, as well as for five ancient biallelic mutation events: two poly (A) length variants associated with the YAP insertion, two independent SRY-1532 mutations, and the 92R7 mutation. We have used our previously published pedigree data from 11,000 paternity-tested autosomal STR-allele transfers to produce a two-class weighting system for the Y-STR loci that is based on locus lengths and motif lengths. Reduced-median-network analysis yields a phylogeny that is independently supported by the five biallelic mutations, with an error of 6%. We find the earliest branch in our African San (Bushmen) sample. Assuming an age of 20,000 years for the Native American DYS199 T mutation, we estimate a mutation rate of 2.6x10-4 mutations/20 years for slowly mutating Y STRs, approximately 10-fold slower than the published average pedigree rate.

Africa↗
PubMed2000

Microsatellite structures in the context of human evolution.

Six microsatellite - or short tandem repeat (STR) - systems with uniform repetitive sequences (HumTH01, HumCD4, HumFES/FPS, HumF13B, HumTPO, HumLPL) and three compound repeat systems (HumVWA, HumFIBRA, D21S11) were used, including data from the literature, to determine genetic distances among eight populations worldwide. The TH01- and VWA homologous loci in nonhuman primates (chimpanzees, gorillas, orangutans, rhesus monkeys, ring-tailed lemurs) were compared and found to be shorter than in humans. Microsatellites of lower complexity were most efficient for the separation of major ethnic groups. The loci of higher complexity showed a leveling of the diversity differences among populations, which could be attributed to higher mutation rates.

Animals↗
PubMed2000

Post-mortem orthopantomography--an aid in screening for identification purposes.

Ante-mortem orthopantomograms may be of great value in the identification of human remains. This x-ray technique provides an overall view of the teeth and jaws and thus of numerous individual structural characteristics within a short time. Standardised post-mortem orthopantomography has previously not been feasible in the forensic practice. The present study shows how orthopantomography can be applied to identification procedures. The reproduction of ante-mortem x-ray conditions is implemented here in the production of post-mortem x-rays, using a purpose-designed radiographic tripod. For the first time, account is taken not only of the size and structure but also of the nature of the soft tissue covering of exhibits. For post-mortem preparation of these radiographs, appropriate positioning aids, a spinal column substitute and a soft tissue filter were constructed. Individual macerated jaws as well as the complete cranium can now be positioned correctly in the upright orthopantomograph (OPG). The method presented expands the spectrum of forensic radiology for the individual case and in our opinion also offers a reliable aid for victim identification in the wake of mass disasters, aircraft crashes and terrorist attacks, where a large number of bodies have to be identified under great pressure.

Cadaver↗
PubMed2000

Demonstration of myocardial necrosis in the presence of advanced putrefaction.

Samples of heart tissue were investigated in two series for the detectability of myocardial necrosis after artificial and natural putrefaction, respectively. In the first series heart tissue with and without infarction was artificially subjected to humid and dry autolysis and putrefaction. In the second investigation heart tissue was obtained from exhumed bodies after periods of burial ranging between 10 and 929 days. Besides histology a variety of immunohistochemical markers were applied and C5b-9 gave positive results even after long periods of artificial and natural putrefaction. From the methods tested, this was by far the most sensitive method with a high robustness against putrefaction. NP57, which indicates neutrophilic leucocytes could be demonstrated considerably longer after humid putrefaction than after dry putrefaction. The time limits of detection were considerably longer than for H&E. These two methods are the methods of choice for the detection of myocardial infarction and leucocyte infiltration in advanced stages of putrefaction.

Adult↗
PubMed2000

Development of haemoglobin subtypes and extramedullary haematopoiesis in young rats. Effects of hypercapnic and hypoxic environment.

The influence of repeated hypoxia on the development of haemoglobin (Hb) subtypes and on extramedullary haematopoiesis (EMH) was investigated in young Wistar rats of different ages. The rats were exposed to hypercapnic/hypoxic and to "simple" hypoxic conditions. The results obtained were compared to those of an untreated age-matched control group. Different globin chains were measured using HPLC and time-of-flight (TOF) mass analysis. The number of EMH cells was evaluated by cell counting. By determining the proportions of alpha- and beta-chains, fetal, neonatal and mature types of globin chain composition could be differentiated. The beta-2 chain levels were significantly higher in hypercapnic/hypoxic environments than in the controls and simple hypoxic environments. The numbers of EMH cells in the two groups subjected to hypercapnia/hypoxia decreased significantly more slowly compared to the controls and simple hypoxia groups. Therefore, the development of Hb subtypes and the EMH activity in rats were influenced by both repeated hypercapnia and hypoxia.

Animals↗
PubMed2000

Influence of different staining techniques on the DNA analysis of histological sections.

The use of stained histological sections as a source for DNA may be necessary in forensic case work if confusion of tissue is suspected, for identification or paternity cases. To elucidate the influence of different staining techniques on the PCR amplification of DNA, histological sections of liver tissue were prepared using eight different staining techniques and two histochemical methods. The DNA of the sections was extracted by a modified Chelex extraction and amplified using a commercial triplex kit. Staining with hematoxylin-eosin, hemalum-eosin, azan, periodic acid-schiff and prussian blue showed no adverse effect on the amplification of DNA while the extracts of tissue stained by Masson-Goldner, Ladewig and elastica-van Gieson methods had to be purified before amplification was possible. Staining with phosphoric tungsten acid hematoxylin and Gomori led to a degradation of DNA probably due to the use of potassium permanganate solution.

Adult↗
PubMed2000

Stability of carbohydrate deficient transferrin (CDT) in stored blood samples.

The alcoholism marker CDT was determined on 257 blood samples 1-2 days after the blood samples were taken and again after storage for 7 months at +4 degrees C. The differences between the pairs of CDT values were so large that the determination of CDT after long term storage of the blood sample has no evidential value.

Alcoholism↗
PubMed2000

Suicide of a diabetic by inducing hyperglycemic coma.

Deaths due to hyperglycemic and hyperosmolar coma in diabetics are usually disease-related. In the exceptional case reported here there was evidence for an intentional ingestion of a sugar solution, the person was a diabetic and known to be depressive suggesting a suicidal intention. The autopsy findings were inconspicuous and only further laboratory findings led to the final diagnosis.

Aged↗
PubMed2000

Criminal anticipation of DNA investigations resulting in mutilation of a corpse.

A corpse of a female was found in her apartment in a state of advanced putrefaction. Both hands were amputated, the external genitals were excised and the body parts had been removed from the scene. The subsequent investigations proved that the body parts had been severed post mortem. The cause of death was determined to be manual strangulation. A 33-year-old man later confessed that he had strangled the victim 9 days prior to discovery of the body and that he had had sexual intercourse post mortem. According to the confession, the rational motive for the subsequent mutilation was to eliminate biological stains (e.g. semen inside the vagina, epithelial cells below the fingernails from scratching) suitable for forensic DNA analysis. This constitutes a new type of defensive mutilation intended to prevent the identification of the perpetrator. An increase in the occurrence would be detrimental to the elucidation rate of homicides: in a total of 171 homicides investigated at this institute, DNA analysis of biological stains gave reliable evidence in 45 cases.

Adult↗
PubMed2000

Suicides by sharp force: typical and atypical features.

A total of 65 consecutive cases of suicide by sharp force were investigated by evaluating the autopsy and prosecution department records. Suicides constituted 17% of all fatalities from sharp force autopsied between 1967 and 1996. Young males and persons with a psychiatric history predominated among the persons who chose this "hard" method of suicide. The most common implements used were knives (62%) and razor blades (15%). Cutting injuries in isolation were present in 26, stab injuries in isolation in 24 and a combination of both in 15 fatalities. The number of injuries per case varied from 1 to 37 but 1/3 showed one injury. More than 85% of the cutting injuries were located at the wrist, elbow crease or neck whereas 79% of the stab injuries involved the ventral aspect of the trunk. Perforation of clothing was present in 16 (52%) out of 31 stab injuries to the trunk. Injuries to more than one body region were observed in 34 (52%) cases. Tentative marks were present in 50 (77%) fatalities and the number varied from 1 to 60 per case. Superficial incisions of the fingers were found in 15% with razor blades constituting the weapon in half of these cases. Deviations from these typical patterns occurred not infrequently. The utter determination of the victim to carry it through or the use of unusual weapons resulted in a few bizarre cases which are outlined briefly.

Abdominal Injuries↗
PubMed2000

A comparative study on the immunohistochemical detection of early myocardial damage.

The study was undertaken to evaluate the kinetics and distribution patterns of several immunohistochemical markers in ischemically and hypoxically damaged myocardium. The myocardium of 8 cases of acute myocardial infarction (AMI), 8 cases of diagnosed acute cardiac death (ACD) and 12 cases of acute exogenic hypoxia (AEH) due to CO poisoning or hanging were analysed for depletion of the cardiac antigens FABP, troponin C and T, desmin and myoglobin, loss of CD59 and deposition of the plasma antigens fibrinogen, fibronectin and the terminal complement complex C5b-9. The visualisation of the terminal complement complex was positive as early as 30 min after onset of symptoms of AMI. Depletion of cellular antigens started earlier than the deposition of plasma antigens. The deposition of fibronectin and fibrinogen began earlier than the detection of C5b-9 but later than the depletion of the cellular antigens. Our findings indicate that for the immunohistochemical detection of very early myocardial damage, the depletion of myoglobin is at least of the same rank or better than depletion of FABP and troponin.

Adolescent↗
PubMed2000

Thickness of the air-blood tissue barrier in infants.

The harmonic mean barrier thickness of the alveolar air-blood tissue barrier was measured in nine SIDS cases, six cases of unnatural death (three with asphyxiation, three without asphyxiation) and six cases showing interstitial pneumonia (IP, three cases with lymphomonocyte infiltration of alveolar walls, three cases with peribronchiolar infiltration). Approximately 550-600 measurements were carried out in each case using micrographs with a final magnification of 11,000. The Th values ranged between 0.37 micron and 0.39 micron in the SIDS group, in deaths due to asphyxiation and IP with a peribronchiolar type of infiltration, were lowest in the unnatural deaths without asphyxiation (0.32 micron) and highest in cases showing IP with alveoloseptal infiltration (0.44 micron). The differences between the groups were significant (H-test, Hcor = 5.927). Compared to "normal" unnatural deaths (Th = 0.32 micron), cases with interstitial cell infiltration of the alveolar septa showed a nearly 40% increase of the barrier thickness which indicates a corresponding decrease of the diffusion capacity. A decreased diffusion capacity can cause hypoxemia which could be an additional trigger mechanism in the death process.

Age Factors↗
PubMed2000

ROC analysis of alcoholism markers--100% specificity.

A combination of 4 so-called markers of alcoholism, i.e. methanol, acetone + 2-propanol, gamma-glutamyltransferase and carbohydrate deficient transferrin, was investigated in 341 blood samples from alcoholics and non-alcoholics. From the history of alcohol consumption, four defined subgroups were formed: non-alcoholics divided into (A) 33 persons with no ethanol consumption during the past year and (B) 60 persons with daily consumption less than 40 g ethanol. Alcoholics were divided into (C) 177 persons with no ethanol at the time of admission/first blood sampling (withdrawal therapy) and (D) 71 persons with positive ethanol levels on admission/first blood sampling. All markers showed different extents of overlap between the collectives of alcoholics and non-alcoholics. By logistic regression, a formula was developed combining these markers with different mathematical weights. Thus an "Alc-Index" could be calculated for each individual. The ROC curve connecting all individual values gives an ideal form with 100% specificity and nearly 93% sensitivity. The threshold between the collectives of alcoholics and non-alcoholics was defined by the Alc-Index value 1.7. This was associated with no false positives among the non-alcoholics while nearly 93% of the alcoholics exceeded this index. The ROC-based calculation of the Alc-Index thus seems to be the most effective method for the diagnosis of alcoholism.

1-Propanol↗
PubMed2000

The carbohydrate deposits detected by histochemical methods in the molecular layer of the dentate gyrus in the hippocampal formation of patients with schizophrenia, Down's syndrome and dementia, and aged person.

Post-mortem brain tissue was obtained from 28 patients with brain disorders, of which 15 had clinically diagnosed schizophrenia, 6 Alzheimer type dementia, 5 dementia with tangles and 2 cases of Down's syndrome. The controls were 22 cases from autopsies without brain disorders or with no known episodes of brain disorder. The tissues were stained for the detection of carbohydrate deposits in the hippocampal formation, using lectin, immunohistochemical and conventional staining methods. The staining revealed the existence of spherical deposits in the inner and middle molecular layers of the dentate gyrus in the hippocampal formation which contained fucose, galactose, N-acetyl galactosamine, N-acetyl glucosamine, sialic acid, mannose and chondroitin sulfate. The number of the deposits was higher in patients with brain disorder such as schizophrenia, Alzheimer type dementia, dementia with tangles or Down's syndrome, and in some aged individuals, in comparison to those in younger individuals. No deposits were detected in a few younger or aged individuals. Spherical deposits 3-10 microm in diameter may be an immature form of the corpora amylacea, since they were similar in the histochemical characteristics with lectin, immunohistochemical and conventional staining methods. However, differing staining ability by hematoxylin, periodic acid Schiff's reagent and antibodies against the intracellular degraded proteins such as ubiquitin and tau-protein was observed. The antibodies against ubiquitin and tau-protein showed clear reactivity with the corpora amylacea and no reactivity with spherical deposits, indicating that the corpora amylacea has an intracellular origin and spherical deposits an extracellular matrix origin. The results obtained in this study indicate that not only neuronal degeneration but also unusual glycometabolism in neurons may disturb the neuronal function and cause brain disorders, and that spherical deposits may cause dysfunction of the neuronal network in the dentate gyrus of the hippocampus which is closely linked with recognition and memory functions.

Adult↗