Biomedical subjects

Burkhard Madea

Publications and source records attributed to Burkhard Madea.

At least 19 recordsLinked to original sources

PubMed2006

New trends in hair analysis and scientific demands on validation and technical notes.

This review focuses on basic aspects of method development and validation of hair testing procedures. Quality assurance is a major issue in drug testing in hair resulting in new recommendations, validation procedures and inter-laboratory comparisons. Furthermore recent trends in research concerning hair analysis are discussed, namely mechanisms of drug incorporation and retention, novel analytical procedures (especially ones using liquid chromatography-mass spectrometry (LC-MS) and alternative sample preparation techniques like solid-phase microextraction (SPME)), the determination of THC-COOH in hair samples, hair testing in drug-facilitated crimes, enantioselective hair testing procedures and the importance of hair analysis in clinical trials. Hair testing in analytical toxicology is still an area in need of further research.

Forensic Toxicology↗

PubMed2006

Demands on scientific studies: vitality of wounds and wound age estimation.

Research on vitality and wound age estimation belongs to the classic fields in forensic medicine. Despite large literature data there is still considerable demand of further research and practical transfer of knowledge and techniques to daily casework. Scientific studies must fulfil basic criteria as to appropriate methods, selection of case material, analysis of results and quality control. Nowadays, immunohistochemistry, biochemical tests and molecular biological techniques are mainly used studying questions of vitality and wound age. Investigations can be based on human tissue samples (autopsy material, vital specimens) or animal experiments. The possibilities, advantages and disadvantages of these study designs are described. Indispensable is the use of appropriate control groups or control samples and a sufficient case number which permits statistical analysis. Main strategy is to minimize variations due to methods and investigators as the unavoidable biological variation of vitality processes and wound repair is large enough.

Ethics, Research↗

PubMed2006

Sudden infant death syndrome (SIDS)--standardised investigations and classification: recommendations.

Sudden infant death syndrome (SIDS) still accounts for considerable numbers of unexpected infant deaths in many countries. While numerous theories have been advanced to explain these events, it is increasingly clear that this group of infant deaths results from the complex interaction of a variety of heritable and idiosyncratic endogenous factors interacting with exogenous factors. This has been elegantly summarised in the "three hit" or "triple risk" model. Contradictions and lack of consistencies in the literature have arisen from diverse autopsy approaches, variable applications of diagnostic criteria and inconsistent use of definitions. An approach to sudden infant death is outlined with discussion of appropriate tissue sampling, ancillary investigations and the use of controls in research projects. Standardisation of infant death investigations with the application of uniform definitions and protocols will ensure optimal investigation of individual cases and enable international comparisons of trends.

Bacteriological Techniques↗

PubMed2006

Tasks of research in forensic medicine - different study types in clinical research and forensic medicine.

In the last years the research output of forensic medicine has sometimes been regarded as insufficient and as of poor quality, especially when parameters as impact factors and external funding were taken into account. However, forensic medicine has different tasks compared to clinical medicine. The main difference between basic subjects, clinical and forensic medicine is not a lack of scientific efficiency in forensic medicine but is a result of the questions asked, the available methods and specific aims. In contrast to natural-scientific research, forensic science has furthermore important intersections with arts and socio-scientific disciplines. Etiologic and pathogenetic research is of only limited relevance in forensic medicine. Thus, forensic medicine is excluded from these research fields, which are mainly supported by external funding. In forensic medicine research mainly means applied research regarding findings, the probative value and reconstruction as well as examination at different points of intersection between medicine and law. Clinical types of research such as controlled randomised, prospective cross-sectional, cohort or case-control studies can only rarely be applied in forensic medicine due to the area specific research fields (e.g. thantatology, violent death, vitality, traffic medicine, analytical toxicology, hemogenetics and stain analysis). The types of studies which are successfully established in forensic medicine are comparison of methods, sensitivity studies, validation of methods, kinetic examinations etc. Tasks of research in forensic medicine and study types, which may be applied will be addressed.

Biomedical Research↗

PubMed2006

Estimation of the time since death.

The main principle of the determination of the time since death is the calculation of a measurable date along a time-dependent curve back to the start point. Characteristics of the curve (e.g. the slope) and the start point are influenced by internal and external, antemortem and postmortem conditions. These influencing factors have to be taken into consideration quantitatively in order to improve the precision of death time estimation. It does not make any sense to study the postmortem time course of any analyte without considering influencing factors and giving statistical parameters of the variability. Comparison of different methods requires an investigation of the same postmortem interval. For practical purposes, it must be concluded that the amount of literature on estimating the time since death has a reverse correlation with its importance in practice.

Forensic Medicine↗

PubMed2006

Case histories in forensic medicine.

Case histories make up a great part of publications in forensic medicine, especially forensic pathology, although considered low on the hierarchy of evidence based medicine because of its inherent anecdotal nature. Meanwhile some journals exclude case histories categorically from publication. The boom of case histories in forensic medicine has not only opportunity reasons (easily [even mental] and cheap to do) but also structural reasons: due to its tasks in case work many items of forensic medicine can not be simulated experimentally for ethical reasons (violent death, traumatic injuries, sexual assault, poisonings, influence of alcohol and drugs on driving ability and legal responsibility, medical malpractice, adverse events during medical care). In these fields the role of case histories is mainly the augmentation of experience based knowledge. However, quality aspects have to be considered and case histories should be the basis for systematic or hypothesis based research.

Forensic Medicine↗

PubMed2006

Future in forensic medicine as an academic discipline--focussing on research.

Based on a short description of the areas of operation and competence of forensic medicine, current problems, structural deficits of the speciality and possible solutions are discussed. To give future to legal medicine as an academic discipline, research must be given priority over routine casework.

Forensic Sciences↗

PubMed2006

Postmortem biochemistry.

Postmortem biochemistry may provide significant information in determining the cause of death. Due to the rapid postmortem breakdown of metabolism and active membrane transport only analytes which are stable in blood can be determined on this fluid compartment, other parameters have to be analysed on other fluid compartments like vitreous humor (VH). However, using another fluid compartment as a mirror of blood at the moment of death involves severe methodical problems. The conceptual problems of reference values in vitreous humor as a mirror of blood are addressed. Additionally, the necessary steps to be taken before calculating the discriminating values between "normal" and "diseased" are described. For all chemical determinations, a clear definition of the site of sample acquisition is necessary. Up to now chemical determinations on alternative fluids have mainly been carried out using instruments calibrated for urine or serum. Developing calibrated methods for analysis of alternative fluids is a further task for the future.

Biomarkers↗

PubMed2006

Fatal Candida tropicalis infection in an 8-month-old infant with an aplasia of the thymus as a rare cause of death in infancy.

UNLABELLED: Anomalies of the thymus can lead to immunodeficiencies that are often associated with complex syndromes. The clinical relevance of those anomalies varies a lot. Regarding mortality and morbidity, opportunistic infections play a major role in immunocompromised individuals. CASE REPORT: An 8-month-old infant died of a sepsis with multi-organ failure after 32 days in intensive care. At autopsy, no thymus gland could be found; toxicological examinations yielded high morphine concentrations. Autopsy findings and the results of further examinations performed postmortem are discussed in view of the clinical findings, the classification and the cause of death.

Analgesics, Opioid↗

PubMed2006

Time of death dependent criteria in vitreous humor: accuracy of estimating the time since death.

Since more than 40 years reports on the rise of potassium concentration [K(+)] in vitreous humor have been published with different statements concerning the accuracy of death time estimation. In the last years several statistical approaches for a more accurate estimation of the time since death have been reported. While in most investigations the PMI has been used as the independent and [K(+)] as the dependent variable in linear regression analysis between PMI and [K(+)], recently it has been suggested to use [K(+)] as the independent variable for regression analysis. Changing the variables would lead to a higher accuracy of death time estimation. This has also been recommended for regression analysis between hypoxanthine concentration [Hx] and time since death. This hypothesis has been checked on independent cases with potassium and hypoxanthine in vitreous humor. Linear regression with [K(+)] or [Hx] as independent variable has revealed a slightly more accurate death time estimation compared to a linear regression with PMI as independent variable. Thus, e.g. the accuracy could have been improved from +/-25.96 to +/- 23.27h by using [K(+)] as independent variable. Another statistical approach has re-evaluated six large studies on the rise of vitreous [K(+)] using a local regression analysis (Loess procedure). Based on this re-evaluation an accuracy of death time estimation has been recommended (95% limits of confidence of +/-1h in the early PMI and +/-10h, 110h postmortem) which has surpassed even optimistic results of earlier investigations. This recommended accuracy of death time estimation has been checked on a random sample of 492 cases. Only 153 cases have been within the predicted postmortem interval, 339 lay outside with a systematic overestimation of the time since death.

Chromatography, High Pressure Liquid↗

PubMed2006

Enantiomeric determination of tramadol and O-desmethyltramadol by liquid chromatography- mass spectrometry and application to postoperative patients receiving tramadol.

A liquid chromatographic-mass spectrometric assay with atmospheric pressure chemical ionization is presented for quantification (selected-ion mode) of tramadol (T) and O-desmethyltramadol (ODT) in blood plasma after liquid-liquid extraction. The enantiomeric separation was achieved on a Chiralpak AD column containing amylose tris-(3,5-dimethylphenylcarbamate) as chiral selector. The validation data were within acceptable limits. The assay was successfully applied to authentic plasma samples allowing confirmation of diagnosis of overdose or intoxication as well as monitoring of patients' compliance. In postoperative patients receiving T, mean therapeutic plasma concentrations were determined as follows: 422.8 and 440.8 ng/mL for (+)-T and (-)-T, respectively, and 23.7 and 40.7 ng/mL for (+)-ODT and (-)-ODT, respectively. Quantitative results demonstrated a great interindividual variability in postoperative plasma analgesic drug concentrations and, therefore, a wide therapeutic concentration range. The 7.7% of the samples that revealed negative results for ODT are likely explained by genetic polymorphisms resulting in absent enzyme activity of CYP2D6.

Analgesics, Opioid↗

PubMed2006

The significance of putative urinary markers of illicit heroin use after consumption of poppy seed products.

After consumption of poppy seeds various substances were detected in urine or blood samples using an immunoassay and a sophisticated liquid chromatographic-tandem mass spectrometric procedure. These compounds are widely considered to be putative markers of heroin (HER) abuse whereas acetylcodeine was regarded as a marker for illicit preparations ("street HER"). Besides positive urinary opiate immunoassay results during a 48 hours monitoring period, peak concentrations of morphine (MOR), codeine and their glucuronides appeared 4 to 8 hours after ingestion of poppy seeds, and concentrations of total MOR higher than 10 microg/mL were observed. Also, in serum samples taken up to 6 hours after consumption, MOR glucuronides were found. Free MOR was only detected in traces (1 to 3 ng/mL) within 2 hours of consumption. In addition, 3 of 6 onsite opiate sweat tests revealed positive results 6.5 hours after ingestion. Furthermore, it was demonstrated that neither noscapine (NOS) nor papaverine (PAP) was detectable in urine or blood samples after the consumption of poppy seeds containing up to 94 microg NOS and up to 3.3 mug PAP. NOS and PAP were rapidly metabolized, whereas desmethylpapaverine and, especially, its glucuronide were found in urine samples of poppy seed consumers even 48 hours after consumption. According to these results PAP metabolites should not be regarded as markers of illicit HER abuse. In conclusion, only acetylcodeine can be regarded as a specific marker but has the problem of a short half-life. Therefore, we suggest that NOS and PAP, but not their metabolites, might be used cautiously as additional markers of illicit HER abuse as they have not been detected after oral intake of poppy seeds in normal doses. But it must be kept in mind that in some cases poppy seeds with an unusually high content of these alkaloids could be available, and that these substances are also agents in some pharmaceuticals.

Biomarkers↗

PubMed2006

Review of biologic matrices (urine, blood, hair) as indicators of recent or ongoing cannabis use.

Especially for cannabinoids, analytical procedures for the verification of recent use and generally for the assessment of the extent of drug abuse are of interest in clinical and forensic toxicology. For confirmation of abstinence, urine analysis seems to be a useful tool. Serial monitoring of THC-COOH to creatinine ratios can differentiate between recent drug use and residual THC-COOH excretion (THC-COOH/creatinine ratio > or = 0.5 compared with previous specimen ratio). For an assessment of the extent of cannabis use, the determination of free and bound THC-COOH and especially of THC and 11-OH-THC glucuronides are suggested as useful but need further confirmation. Blood analysis is preferred for the interpretation of acute effects after cannabis abuse. The cannabis influence factor (CIF) was demonstrated as a better tool to interpret the concentrations of THC and its metabolites in blood in forensic cases and therefore it was proposed to assume absolute driving inability because of cannabis intoxication from a CIF > or = 10. Additionally, a higher CIF is indicative of a recent cannabis abuse. Also discrimination between occasional use of cannabis and regular drug consumption is possible by analysis of THC-COOH in blood samples because of the long plasma half-life of THC-COOH and its accumulation in the blood of frequent cannabis consumers. In routine tests, blood samples have to be taken within a prescribed 8-day-period, and a THC-COOH concentration >75 ng/mL is assumed to be associated with regular consumption of cannabis products, whereas plasma THC-COOH concentrations <5 ng/mL are associated with occasional consumption. In contrast to other illicit drugs, hair analysis lacks the sensitivity to act as a detector for cannabinoids. THC and especially the main metabolite THC-COOH have a very low incorporation rate into hair and THC is not highly bound to melanin, resulting in much lower concentrations in hair compared with other drugs. Additionally, THC is present in cannabis smoke and also can be incorporated into the hair only by contamination. For the determination of the main metabolite THC-COOH in the picogram or femtogram per milligram range, which indicates an active consumption, special analytical procedures, such as GC/MS/MS techniques, are required.

Hair↗

PubMed2006

Accidental autoerotic death by volatile substance abuse or nonsexually motivated accidents?

In contrast to typical autoerotic fatalities, when death is due to asphyxia mostly by mechanical compression of the neck, atypical autoerotic accidental deaths (AADs) involve sexual self-stimulation by other means such as electrocution or inhalation of chemical agents. Especially in lethal cases of volatile substance abuse (VSA), a differentiation between suicide or sexually or nonsexually motivated accident is often complicated in practical casework. Considering the small number of AADs involving chemical substance abuse reported in the literature, the number of unreported cases seems to be very high. We report about 5 lethal cases of VSA; analysis was performed using headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC/MS). When headspace sampling is not performed at autopsy, the analysis of volatile substances can be very complicated. In 2 cases, an AAD was diagnosed considering findings at the scene, reconstruction of the event, and discussion of the circumstances of the death. These findings demonstrate the importance of VSA in atypical autoerotic asphyxia. Therefore, in cases of suspected lethal inhalational intoxications, as a matter of principle, headspace asservation should be performed at autopsy and an autoerotic motivational background should be taken into consideration for differential diagnosis.

Accidents↗

PubMed2006

Histological and immunohistochemical study of Wischnewsky spots in fatal hypothermia.

Wischnewsky spots in the gastric mucosa are considered an important finding for the diagnosis of hypothermia-related deaths. In the present prospective histological and immunohistochemical investigation, 14 cases of fatal hypothermia presenting Wischnewsky spots at autopsy were studied. Macromorphologically, the lesions, varying in diameter from 0.1 to 0.4 cm, had a blackish-brownish color and appeared partly lofty, especially on the apex of gastric folds. Histologically, no erosions or ulcers were observed in the gastric mucosa. In some cases, hemorrhages in conjunction with infarctions of the mucosa were observed in the mucosal glands. Those regions, however, did not represent the lesions visible as Wischnewsky spots at the macroscopical level. Immunohistochemical stains were done with a specific antibody against hemoglobin (Dako, Glostrup, Denmark). Wischnewsky spots expressed immunopositivity with antihemoglobin. Concerning the pathogenesis and underlying pathophysiologic mechanisms contributing to the development of Wischnewsky spots, we hypothesize that cooling of the body in the setting of cold ambient temperatures primarily leads to circumscribed hemorrhages of the gastric glands in vivo or in the agonal period, respectively. Subsequently, due to autolysis, erythrocytes are destroyed and hemoglobin is released. Following exposure to gastric acid, hemoglobin is hematinized, leading to the typical blackish-brownish appearance of Wischnewsky spots seen at gross examination. Wischnewsky spots are not equivalent to erosions in terms of histopathological diagnosis but rather represent epiphenomena generated in vivo or in the agonal period of fatal hypothermia.

Adult↗

PubMed2005

Determination of opiates and cocaine in hair using automated enzyme immunoassay screening methodologies followed by gas chromatographic-mass spectrometric (GC-MS) confirmation.

The objective of this study was to develop a two-step strategy for analysis of opiates and cocaine in hair samples involving an immunological screening procedure followed by confirmation of results using gas chromatography-mass spectrometry (GC-MS). A semi-quantitative automated competitive enzyme-linked immunosorbent assay (ELISA) methodology using Oral Fluid Micro-Plate Enzyme Immunoassays (Orasure Technologies, Inc.) was developed and validated. Applicability was proven by analysis of authentic head hair samples from drug users (n=103) and from opiate associated fatalities (n=21). The optimum cutoff values for the ELISA tests were 0.1 ng cocaine-equivalents/mg hair and 0.05 ng morphine-equivalents/mg hair using a 50 mg hair sample. Both ELISA tests had a sensitivity of 100%, the specificity was 66% for cocaine-equivalents and 42% for morphine-equivalents. The intraassay precision was 11% for the cocaine and 3% for the opiates ELISA, while interassay precision was 12% for the cocaine and 4% for the opiates ELISA test. The actual analyte concentrations in the hair samples were determined using GC-MS and were between 0.04 and 5.20 ng/mg for heroin (HER), between 0.04 and 30.01 ng/mg for 6-monoacetylmorphine (MAM), between 0.03 and 11.87 ng/mg for morphine (MOR), between 0.02 and 1.84 ng/mg for codeine (COD), between 0.02 and 2.48 ng/mg for acetylcodeine (AC), between 0.01 and 21.37 ng/mg for cocaine (COC), between 0.03 and 10.51 ng/mg for benzoylecgonine (BE) and between 0.05 and 1.26 ng/mg for cocaethylene (CE). The automated ELISA tests were proven to be valid screening procedures for the detection of cocaine and opiates in hair as confirmed by GC-MS. Screening methods provide rapid and inexpensive automated pre-test procedures to detect drugs in hair or other matrices. For forensic purposes screening therefore represents an ideal complement to routinely applied GC-MS procedures.

Case-Control Studies↗

PubMed2005

Noradrenergic modulation of emotion-induced forgetting and remembering.

We used a free-recall paradigm to establish a behavioral index of the retrograde and anterograde interference of emotion with episodic memory encoding. In two experiments involving 78 subjects, we show that negatively valenced items elicit retrograde amnesia, whereas positively valenced items elicit retrograde hypermnesia. These data indicate item valence is critical in determining retrograde amnesia and retrograde hypermnesia. In contrast, we show that item arousal induces an anterograde amnesic effect, consistent with the idea that a valence-evoked arousal mechanism compromises anterograde episodic encoding. Randomized double-blind administration of the beta-adrenoceptor antagonist propranolol compared with the selective norepinephrine (NE) reuptake-inhibitor reboxetine, and placebo, demonstrated that the magnitude of this emotional amnesia and hypermnesia can be upregulated and downregulated as a function of emotional arousal and central NE signaling. We conclude that a differential processing of emotional arousal and valence influences how the brain remembers and forgets.

Adrenergic Uptake Inhibitors↗

PubMed2005

Is there recent progress in the estimation of the postmortem interval by means of thanatochemistry?

Numerous methods have been proposed in the last 60 years for the determination of the time since death by chemical means. Many of them were reviewed by Schleyer in his monograph on the determination of the time since death by means of thanatochemistry about 40 years ago and none of these early methods has gained any practical value since they do not meet the demands in practice (being precise, reliable, giving an immediate result). While the earlier studies were mainly carried out on blood and cerebrospinal fluid (CSF) since the late 60s most investigations have been performed on vitreous humor (VH). This is mainly due to the fact that vitreous humor is topographically isolated and well protected, and thus, autolytic changes proceed slower compared to blood and CSF. The most studied parameter in VH is potassium and even nowadays reports on the postmortem rise of vitreous potassium are published, proposing new analytical methods or statistical evaluations. Chemical parameters studied for the determination of the time since death have to be differentiated according to the underlying process (catabolism, metabolic processes, pure autolysis and diffusion, putrefactive changes). In the present paper, recent studies on thanatochemistry are discussed regarding the underlying process, the analytical methods (for instance H magnetic resonance spectroscopy (1H MR spectroscopy), immunohistochemistry), the studied fluid compartment, the statistical evaluation and the precision of death time estimation. The value of chemical methods for the determination of the time since death is up to now very limited. This is supported by the fact that field studies on the reliability and precision of death time estimation by chemical means are still scarce in the literature.

DNA↗