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W Bonte

Publications and source records attributed to W Bonte.

At least 19 recordsLinked to original sources
PubMed1999

Stability of RNA transcripts in post-mortem psychiatric brains.

RNA isolated from frozen human post-mortem brain tissue was used for analysis of five gene products with a recently developed sensitive and competitive RT-PCR technique. Samples varying in post-mortem intervals up to four days from controls, schizophrenics and alcoholics were analyzed. Evaluation of three housekeeping genes, as well as Trk B and Trk C demonstrated that the levels of mRNA transcripts were stable in brain samples at all time periods (one to four days) examined. This observation demonstrates that this RT-PCR protocol is a sensitive and reliable method to study relative amounts of mRNAs. The overall stability of housekeeping transcripts implicates the value of post-mortem brain samples for differential gene expression studies.

Actins↗
PubMed1999

DNA-PCR analysis of bloodstains sampled by the polyvinyl-alcohol method.

Among the usual techniques of sampling gunshot residues (GSR), the polyvinyl-alcohol method (PVAL) includes the advantage of embedding all particles, foreign bodies and stains on the surface of the shooter's hand in exact and reproducible topographic localization. The aim of the present study on ten persons killed by firearms was to check the possibility of DNA-PCR typing of blood traces embedded in the PVAL gloves in a second step following GSR analysis. The results of these examinations verify that the PVAL technique does not include factors that inhibit successful PCR typing. Thus the PVAL method can be recommended as a combination technique to secure and preserve inorganic and biological traces at the same time.

Blood Stains↗
PubMed1998

Rapid method for successful HLA class I and II typing from cadaveric blood for direct matching in cornea transplantation.

BACKGROUND: The aim of the study was to establish fast methods for postmortem HLA class I and II typing of cornea donors using cadaveric blood. METHODS: The commercially available reagents Lymphokwik MN and Dynabeads were evaluated here to provide an enriched living mononuclear cell (MNC) population and B-cell population for HLA class I and II typing of cadaveric blood by serology. Cadaveric blood was obtained 1-80 h post mortem. After isolation of living B-cells and B-cell-depleted living MNC's, cells were serologically typed by double-fluorescence cytotoxicity assay for HLA class I and II antigens. RESULTS: In 373 (81%) of 461 cadaveric blood samples HLA class I typing, and in 36 (62%) of 56 cadaveric blood samples HLA-class II typing, by serology was successful and accomplished within 5 h. Results from the serological HLA class I typing were confirmed by the results of HLA class I typing by RNA-based sequencing in seven cases. To improve the HLA class II typing, DNA typing using PCR with sequence-specific primers was performed in 148 samples and reverse hybridization of PCR-amplified DNA to immobilized HLA class II specific primers in 270 samples. These data were confirmed by DNA-based sequencing in five cases and by sequence-specific oligonucleotide hybridization in all cases. CONCLUSIONS: These results lead to the following typing strategy: HLA class I typing should be performed by serology. HLA class II typing should be performed by DNA technology because of its relative independence of the quality of the blood sample. The strategy we have developed is very successful and fast for tissue typing post mortem, thus expanding the time available for ideal HLA matching, increasing the number of available HLA-matched corneas and therefore reducing the number of graft rejections.

Blood Grouping and Crossmatching↗
PubMed1997

Salsolinol and norsalsolinol in human urine samples.

The tetrahydroisoquinoline alkaloids salsolinol and norsalsolinol were found in human urine samples in concentrations ranging from 0.1 to 29.5 ng/ml. Great interindividual variation was found in urine levels of these alkaloids in a collection of chronic alcoholics and in a group of nonalcoholics. Thus, levels of the individual alkaloids are insufficient markers for distinguishing between alcoholics and nonalcoholics. However, by using the concentration ratio of norsalsolinol and salsolinol, the so-called dopamine-aldehyde adduct ratio (DAAR), significant differences between alcoholics (median 1.3) and nonalcoholics (median 0.6) were detected. This concentration ratio could serve as a marker for the processor state of the dopaminergic system.

Alcoholism↗
PubMed1996

Formaldehyde-derived tetrahydroisoquinolines and tetrahydro-beta-carbolines in human urine.

Human urine samples were examined for the occurrence of formaldehyde-derived tetrahydroisoquinolines and tetrahydro-beta-carbolines generated by condensation of the methanol oxidation product with biogenic amines. Positive results were obtained for the tryptamine condensation product 1,2,3,4-tetrahydro-beta-carboline and the serotonine condensation product 6-hydroxy-1,2,3,4-tetrahydro-beta-carboline as well as for the condensation products with tyramine, dopamine, adrenaline and noradrenaline 1,2,3,4-tetrahydroisoquinoline, 6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline, N-methyl-4,6,7-trihydroxy-1,2,3,4-tetrahydroisoquinoline, 4,6,7-trihydroxy-1,2,3,4-tetrahydroisoquinoline, and the metabolite 6-methoxy-7-hydroxy-1,2,3,4-tetrahydroisoquinoline. Negative results were obtained for N-methyl-1,2,3,4-tetrahydroisoquinoline and 6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline, N-methyl-1,2,3,4-tetrahydro-beta-carboline, 6-methyl-1,2,3,4-tetrahydro-beta-carboline, and 6-methoxy-1,2,3,4-tetrahydro-beta-carboline in samples of chronic alcoholics as well as in the urine of healthy volunteers. No correlation between alcohol ingestion or state of alcoholization could be demonstrated.

Alcoholism↗
PubMed1996

German data on the HUMVWA31 locus.

A population study was carried out on Caucasians from Düsseldorf using the short tandem repeat (STR) system HumVWA (von Willebrand factor; locus 12p12-12pter; intron A). After amplification, electrophoresis and silver staining 9 alleles could be detected in the sample of 304 unrelated individuals. No deviations from the Hardy-Weinberg equilibrium could be observed. The results were compared with other population studies.

Alleles↗
PubMed1996

VNTR locus D1S80: allele frequencies and genotype distribution in the region of Düsseldorf.

Hypervariable loci within the human genome are useful tools in several disciplines: for example in forensic medicine (paternity testing and forensic identification). One of these genetical markers is located at chromosome 1 and is called D1S80 (MCT118). The genotype distribution and the allele frequency of the VNTR locus D1S80 have been studied in a population of 378 unrelated Germans living at Düsseldorf. The determination of genotypes has been carried out by using the polymerase chain reaction and subsequent analysis of the amplified products by polyacrylamide electrophoresis followed by silver staining. The data demonstrate that the locus is highly polymorphic with an observed heterozygosity of 75.66%. The frequency distribution found does not meet Hardy-Weinberg expectations. We think that this is not astonishing because we found only 80 of the possible 231 phenotypes (alleles 16-34, 36-37, without anodal and cathodal variants). So before using the D1S80 data in forensic analyses and paternity tests a larger data base has to be established. The data of the Düsseldorf sample are compared with data of studies on other populations.

Alleles↗
PubMed1996

Northrhine Westphalian data on the HumTH01 locus.

A population study was carried out on 302 ethnic Germans from Düsseldorf and 273 ethnic Germans living in Northrhine Westphalia using the short tandem repeat (STR) system HumTH01 (TC11). Seven different alleles were detected. No deviations from the Hardy-Weinberg equilibrium could be observed. The results were compared with other population studies. The pooled sample from Germany can be used as database for forensic purposes.

Adult↗
PubMed1996

Northrhine Westphalian data on the locus F13B.

A population study was carried out on 301 ethnic Germans from Düsseldorf (Northrhine Westphalia) using the short tandem repeat (STR) system HumF13B (Coagulation Factor XIIIB). Five different alleles were detected. No deviations from the Hardy-Weinberg equilibrium could be observed. In spite of the successfulness of the system only a few population data exist. A pooled sample from Northrhine Westphalia has to be used as preliminary database for forensic and anthropological purposes.

Alleles↗
PubMed1996

Düsseldorf data on the PCR-based locus HumFES/FPS (human c-fes/fps proto oncogene).

This paper reports PCR-based genotype distribution and allele frequencies of the locus HumFES/FPS (human c-fes/fps proto oncogene). For this study 300 unrelated Caucasoids of German ancestry living in Düsseldorf were analyzed. Seven of the eight alleles previously described and fourteen of the corresponding thirty-six diploid genotypes were detected. The proportions of heterozygotes and homozygotes observed and expected and the parameters of forensic interest, e.g. the mean paternity exclusion chance, were calculated. No deviations from the Hardy-Weinberg equilibrium were observed. A preliminary German data base (3,238 individuals) was created by using the weighted arithmetical mean which included data from Düsseldorf.

Alleles↗
PubMed1995

[Ethanol-independent methanol elimination in chronic alcoholics].

72% of a collective of chronic alcoholics (DSM-III-R, ICD 9), who were admitted under the influence of alcohol in order to undergo alcohol withdrawal, showed a serum methanol concentration (SMC) above 10 mg/l. This level is usually considered to be the one for the detection of regular alcohol consumption. The SMC values were considerably higher in cases where alcoholic beverages with a higher methanol content were consumed rather than the ones lower in methanol. In the majority of patients a decrease of the methanol concentration could only be detected once an individually varying limit concentration of ethanol (0-0.62 g/kg) was reached. There were, however, a few exceptions where the elimination of methanol independent from the ethanol concentration could be seen. Contrasting the general collective, these 'ethanol independent' methanol eliminators showed a much higher serum level of ethanol and methanol at the time of admission. As a sign of addiction, all patients showed increased beta 60 values for ethanol and preferred high proof beverages, which at the same time have high methanol contents.

Adult↗
PubMed1993

Gas chromatographic-mass spectrometric screening procedure for the identification of formaldehyde-derived tetrahydroisoquinolines in human urine.

A gas chromatographic-mass spectrometric method has been developed for the identification of 1,2,3,4-tetrahydroisoquinoline and six metabolites extracted from urine in the picogram range. The derivatization procedure for the substances, formed by reaction of formaldehyde with biogenic amines, employs propionic anhydride and can take place in aqueous medium. In this way artificial formation of these compounds via condensation of biogenic amines with aldehydes or alpha-keto acids during the work-up procedure is eliminated. The procedure results in hydrophobic compounds, which are quantitatively extractable by liquid-liquid extraction with organic solvents. Further clean-up was performed by solid-phase extraction on C18 sample preparation columns.

Formaldehyde↗
PubMed1993

Gas chromatographic-mass spectrometric screening procedure for the identification of formaldehyde-derived tetrahydro-beta-carbolines in human urine.

A gas chromatographic-mass spectrometric method for the identification of 1,2,3,4-tetrahydro-beta-carboline and four metabolites extracted from urine is described. In a first step the substances, formed by reaction of formaldehyde with biogenic amines, were derivatized in aqueous solution with methyl chloroformate to eliminate an artificial formation of these compounds via condensation of endogenous indole ethylamines with aldehydes or alpha-keto acids during the work-up procedure. This initial derivatization formed stable hydrophobic compounds and improved the extractability for a liquid-liquid extraction. Further clean-up was performed by solid-phase extraction on C18 sample preparation columns. The method can identify these compounds in the picogram range.

Carbolines↗
PubMed1993

Distribution of GC-subtypes in a series of chronic alcoholics.

This article reports on the distribution of GC-(group specific component) subtypes in a series of chronic alcoholics (N = 100). The determination of the phenotypes was carried out by immunoblotting. The results are interpreted and discussed. We observed no association between alcoholism and GC-subtypes.

Alleles↗
PubMed1992

[Forensic assessment of questionable railway suicides].

Railway deaths only seldom give rise to extensive inquiries. For the police there exists no absolute necessity of differentiating between accident and suicide. The reason is that accidents usually do not result in criminal proceedings. For the railway embankment the normal traffic rules are unvalid, and the guilt of the engine driver usually cannot be proven. In consequence these cases very often are declared as suicides without adequate support. This leads to complications in the field of insurance law. Since the "prima facie" principle in these cases was dropped our medicolegal institutes are increasingly engaged with expert opinions dealing with the question of accident or suicide. According to literature only a straight decapitation is regarded as typical for a suicide. But such can be found rather seldom in reality. That was the reason for us to study our own cases and to examine whether there are additional patterns of morphological findings proving a suicidal action. The respective case circumstances and, if available, testimonies were included in our study as well as the special constructional peculiarities of the engine frontages which logically contribute to the appearance of injuries.

Accidents, Traffic↗
PubMed1992

DNA fingerprinting of freeze-dried tissues.

DNA profiling is usually unproblematic when carried out on material sampled shortly after death. Prolonged postmortem intervals and improper storage cause significant DNA degradation, however there are instances where DNA analysis becomes necessary months after the autopsy. In such cases the investigator may be able to revert to material initially stored for toxicological purposes. In some cases such specimens undergo freeze-drying before storage. We have therefore tested DNA fingerprinting of freeze-dried postmortem material. It was found that freeze-drying is a suitable method for preserving tissue samples for DNA profiling.

DNA Fingerprinting↗
PubMed1992

Laryngologic aspects of bolus asphyxiation-bolus death.

Among 12,982 forensic autopsies, 78 cases of café coronary due to bolus impaction in the larynx (bolus death) were observed from 1947 to 1988. In all cases bolus material occluded the entry to the larynx; only once was a singular occlusion of the glottis observed. The bolus frequently extended into the mouth, trachea, and bronchial tree or esophagus. In all cases small amounts of aspirated material were observed in the deeper parts of the bronchial tree. The most commonly observed bolus was not masticated meat or a meat product. In adults and the elderly the bolus was often too large to pass the physiological narrowings of the hypopharynx. It was commonly lodged above the arytenoid cartilages. Forty-five of the bolus events were observed by bystanders. In 43 of the victims vital reactions were observed by bystanders or at the autopsy. This justifies the hope that many lives could have been saved had the right diagnosis and immediate therapy been initiated. The first step should be manual extraction or use of the Heimlich maneuver; in cases of failure of both attempts, immediate tracheotomy followed by hospitalization and bronchial lavage are indicated.

Adolescent↗