Forensische Altersdiagnostik mittels Niederfeld-Magnetresonanztomographie

Hintergrund

Ein rechtlich zulässiges medizinisches Altersfeststellungsverfahren mit möglichst schonenden und zuverlässigen Methoden bei unbegleiteten und fraglich minderjährigen Ausländern ist erforderlich, um den tatsächlich Minderjährigen den für sie gesetzlich vorgesehenen besonderen Schutz zukommen zu lassen.

Ziel der Arbeit

Studiendesign und erste Ergebnisse einer Studie zur forensischen Altersdiagnostik mittels Niederfeld-Magnetresonanztomographie werden vorgestellt.

Material und Methoden

Geplant ist die prospektive Untersuchung von 650 Studienteilnehmenden, gleichmäßig verteilt innerhalb der Altersgruppe 12 bis 24 Jahre zu je 25 Personen je Geschlecht. Es sollen Entwicklungsstadien von distalem Radius, distaler Ulna, distalem Femur und proximaler Tibia mithilfe eines 0,31-Tesla(T)-Niederfeld-MRT-Scanners erfasst und mittels Anwendung der Vieth-Klassifikation ausgewertet werden.

Ergebnisse

Nach Auswertung der Untersuchungen der bisher 487 untersuchten Studienteilnehmenden ist ersichtlich, dass die gewählten Sequenzen die für die Vieth-Klassifikation relevanten Charakteristika der Ossifikation der untersuchten Epiphysen erfassen. Die Untersuchungen erweisen sich überdies als einfach in der Durchführung.

Schlussfolgerung

Untersuchungen zur forensischen Altersschätzung am Lebenden unter Anwendung der Vieth-Klassifikation sind mit Niederfeld-MRT-Scannern bei einer Feldstärke von 0,31 T durchführbar. Es bleibt zu klären, ob die mit einem 0,31-T-Niederfeld-MRT-Scanner nachweisbaren Ossifikationsmerkmale am Handgelenk und am Knie einen zweifelsfreien Volljährigkeitsnachweis erlauben.

What are depressive symptoms in acutely ill patients with schizophrenia spectrum disorder?

Background:

Aim was to examine depressive symptoms in acutely ill schizophrenia patients on a single symptom basis and to evaluate their relationship with positive, negative and general psychopathological symptoms.

Methods:

Two hundred and seventy-eight patients suffering from a schizophrenia spectrum disorder were analysed within a naturalistic study by the German Research Network on Schizophrenia. Using the Calgary Depression Scale for Schizophrenia (CDSS) depressive symptoms were examined and the Positive and Negative Syndrome Scale (PANSS) was applied to assess positive, negative and general symptoms. Correlation and factor analyses were calculated to detect the underlying structure and relationship of the patient’s symptoms.

Results:

The most prevalent depressive symptoms identified were depressed mood (80%), observed depression (62%) and hopelessness (54%). Thirty-nine percent of the patients suffered from depressive symptoms when applying the recommended cut-off of a CDSS total score of > 6 points at admission. Negligible correlations were found between depressive and positive symptoms as well as most PANSS negative and global symptoms despite items on depression, guilt and social withdrawal. The factor analysis revealed that the factor loading with the PANSS negative items accounted for most of the data variance followed by a factor with positive symptoms and three depression-associated factors.

Limitations:

The naturalistic study design does not allow a sufficient control of study results for the effect of different pharmacological treatments possibly influencing the appearance of depressive symptoms.

Conclusion:

Results suggest that depressive symptoms measured with the CDSS are a discrete symptom domain with only partial overlap with positive or negative symptoms.

Unraveling the effects on lithium-ion cathode performance by cation doping M-Li2CuO2 solid solution samples (M = Mn, Fe and Ni)

Cation doping is one of the most dynamic strategies to enhance the electrochemical properties of cathode materials for lithium-ion batteries. Nevertheless, the maximum partial substitution capacity depends on the solubility of each metal ion, and so the formation of impurities is a very common consequence. Thus, the correlation between electrochemical performance and the doping effect is frequently unknown. In this study, the effect of the partial substitution of copper by manganese, iron or nickel in Li2CuO2 is evaluated, as well as the effect on the electrochemical performance of the modified Li2CuO2 samples as lithium ion battery cathode materials. XRD characterization confirmed single phase formation for all samples, and the incorporation of the transition metal in the Li2CuO2 structure was evaluated by XRD profile fitting, EPR and 7Li-NMR. The results showed modifications in intra- and inter-chain interactions, associated with the variations in the Cu-O-Cu bond angle and changes in magnetic order, due to the presence of the doping transition metal. Among all samples, only manganese partial substitution reveals a drastic improvement in the electrochemical stability during the charge/discharge processes even at potentials higher than 3.9 V. It was corroborated that the higher stability is attributed to (i) the increase in the superexchange interactions between the copper sites and manganese, directly modifying lithium diffusivity and electronic conductivity, both inferred from dynamic thermogravimetric analysis for CO2 sorption and conductivity tests, respectively and (ii) the lower propensity to enable O2 evolution during several charge cycles. These results are totally attributed to manganese cation partial substitution, which has a huge impact on the utilization of copper-based materials in real applications.

[On the quality of the external post-mortem examination in cases of fatal head trauma : A comparison of death certificate and forensic autopsy]

BACKGROUND

In Germany it is required by law that basically every type of physician needs to be capable of executing a correct external post-mortem examination of a corpse. In recent years, numerous investigations on external post-mortem examinations repeatedly reported systematic mistakes and erroneous procedures in various clinical and medicolegal case groups. Accordingly, the completion of death certificates is frequently performed incorrectly. As one of the typical unnatural death cases, decedents dying from fatal head trauma (FHT) represent a special autopsy case group, which is expected to be correctly recognized during the primary external post-mortem examination because the external injuries are mostly obvious.

OBJECTIVE

The present study aimed at investigating the quality of the external post-mortem examination in medicolegal FHT cases by means of comparison of death certificates and autopsy reports from a 10-year period.

MATERIAL AND METHODS

In a retrospective study design all autopsy cases from the Institute of Legal Medicine of the University Hospital Münster in the years 2006-2015 (n = 3611) were analyzed as to the presence of FHT. A total of 328 cases with FHT and the concomitant presence of a death certificate filled out before the autopsy were identified. Subsequently, the cause of death according to the death certificate was compared with the cause of death according to the autopsy. The degree of agreement was classified into six different categories from I to VI. While category I represented a complete lack of agreement, category VI was assigned to cases with full agreement.

RESULTS

In 58.5% of the cases (category VI) FHT was identified correctly during the external post-mortem examination. In 1.5% of the cases, a completely different cause of death was determined during the external post-mortem examination (category I). In 19.2% of the cases, no cause of death or the statement "unclear" was given as the cause of death in the death certificate (categories II and III). Cross-analyses and intuitive heatmap visualization were generated to identify case constellations with an increased risk for discrepancies. These analyses revealed that among all discrepant cases (categories I-V), falls were found significantly more often than in the nondiscrepant cases (p < 0.01), especially falls of women older than 57 years (median age of women) or falls considered as accidents by the examiner. In addition, traffic-associated FHT of men older than 44.5 years (median age of men) was identified more frequently in the external post-mortem examination.

CONCLUSION

Despite the fact that FHT should be a cause of death that is comparably easy to identify during external post-mortem examination, more than one third of the cases were not sufficiently recognized. Therefore, special attention must still be paid to certain case constellations during the external post-mortem examination. Typical examples of such cases are burned bodies, cases of advanced putrefaction and falls.

Examination of regressive features of third molars for the purpose of age assessment in the living by means of rescaled regression analyses

The main criterion of dental age assessment in living adolescents and young adults is the evaluation of third molars' mineralization. Concerning forensic age assessment after the completion of third molars' mineralization, apposition of secondary dentine and narrowing of the periodontal membrane as seen as decreasing radiolucent areas in the radiographs for mandibular third molars have already been described as regressive features. The present study examines the combination of both these features for the purpose of age assessment in regression analyses after rescaling the data to make it on the interval scale. To this end, a total of 1245 orthopantomograms was evaluated, taken from 606 females and 639 males in the age group of 15-40 years. The apposition of secondary dentine and narrowing of the periodontal membrane as seen as decreasing radiolucent areas in the radiographs were determined for the lower third molars. The correlation of the features with the chronological age was assessed by means of rescaled regression analyses. Furthermore, regression formulas for age assessment were established. The values of the standard error of estimate ranged between 3.55 and 4.52 years. In general, the rescaled regression of the examined features appears to be suited for forensic age assessment. A limitation of the present study is the comparatively low number of evaluable teeth in the examined age group. Due to an incomplete development or a lack of the mandibular third molars, only a mere half of the respective teeth could be included in the statistical analysis.

Understanding Subdural Collections in Pediatric Abusive Head Trauma

Life-threatening physical abuse of infants and toddlers is frequently correlated with head injuries. A common variant of the abusive head trauma is the shaken baby syndrome. The present review article sheds light on subdural collections in children with abusive head trauma and aims at providing a recent knowledge base for various medical disciplines involved in diagnostic procedures and legal proceedings. To this end, the different subdural collection entities are presented and illustrated. The pathophysiologic background is explained. Differential and age-diagnostic aspects are discussed and summarized by tabular and graphic overviews. Two problematic constellations frequently occurring during initial CT investigations are evaluated: A mixed-density subdural collection does not prove repeated trauma, and hypodense subdural collections are not synonymous with chronicity. The neuroradiologic analysis and assessment of subdural collections may decisively contribute to answering differential diagnostic and forensic questions. In addition to more reference data, a harmonization of terminology and methodology is urgently needed, especially with respect to age-diagnostic aspects.

Characterization of stable and transient cavitation bubbles in a milliflow reactor using a multibubble sonoluminescence quenching technique

The bubble type, generated by an ultrasonic field, was studied in a batch and flow reactor using a multibubble sonoluminescence (MBSL) quenching technique with propanol and acetone. The influence of frequency and transducer configuration was evaluated using the same piezoelectric element in both setups. Results show that the bubble type not only depends on the frequency, but also on the input power or transducer configuration. Additionally, the effect of flow on sonoluminescence yield and bubble type was studied in the continuous setup at various frequencies. As the flow becomes turbulent, the sonoluminescence signal reaches a plateau for three out of four frequencies, and a transition from transient to stable cavitation occurs for frequencies below 200 kHz.

Subdural hygromas in abusive head trauma: pathogenesis, diagnosis, and forensic implications

Are subdural hygromas the result of abusive head trauma? CT and MR imaging represent important tools for the diagnosis of abusive head trauma in living infants. In addition, in-depth understanding of the pathogenesis of subdural hygromas is increasingly required by neuroradiologists, pediatricians, and forensic physicians. Therefore, the current knowledge on subdural hygromas is summarized and forensic conclusions are drawn. The most important diagnostic pitfalls, benign enlargement of the subarachnoid space, and chronic subdural hematoma, are discussed in detail. Illustrative cases from forensic practice are presented. Literature analysis indicates that subdural hygromas can occur immediately or be delayed. If other infrequent reasons can be excluded, the presence of subdural hygromas strongly suggests a posttraumatic state and should prompt the physician to search for other signs of abuse. To differentiate subdural hygromas from other pathologies, additional MR imaging of the infant's head is indispensable after initial CT scan.

Sonographic examination of the apophysis of the iliac crest for forensic age estimation in living persons

The present study examines the applicability of ultrasound diagnostics in assessing the ossification processes of the apophysis of the Crista iliaca of the pelvis for the purposes of forensic age diagnostics in living persons. To this end, the apophyseal ossification stages were determined in 307 female and 309 male study participants aged between 10 and 25 years. In females, ossification stage I was identifiable at an age of 10.1 years at the earliest (x¯=11.8), ossification stage II at 11.2 years at the earliest (x¯=14.6), ossification stage III at 14.7 years at the earliest (x¯ =18.6), and ossification stage IV at 17.9 years at the earliest (x¯=22.7). In males, ossification stage I was observable from an age of 10.0 years (x¯=11.8), ossification stage II from 10.5 years (x¯=14.9), ossification stage III from 15.6 years (x¯=18.9), and ossification stage IV from 17.4 years (x¯=22.6). In forensic age estimation procedures in living persons, sonographic examination of the iliac crest apophysis makes it possible to minimise exposure of the individual to radiation in accordance with the existing legal basis for the use of X-rays on humans. In application areas with no legal basis to justify X-ray examinations, the accuracy of an age diagnosis can be improved by integrating skeletal maturity as a criterion.

Insight in schizophrenia-course and predictors during the acute treatment phase of patients suffering from a schizophrenia spectrum disorder

BACKGROUND

To analyse insight of illness during the course of inpatient treatment, and to identify influencing factors and predictors of insight.

METHODS

Insight into illness was examined in 399 patients using the item G12 of the Positive and Negative Syndrome Scale ("lack of insight and judgement"). Ratings of the PANSS, HAMD, UKU, GAF, SOFAS, SWN-K and Kemp's compliance scale were performed and examined regarding their potential association with insight. The item G12 was kept as an ordinal variable to compare insight between subgroups of patients.

RESULTS

Almost 70% of patients had deficits in their insight into illness at admission. A significant improvement of impairments of insight during the treatment (p<0.0001) was observed. At admission more severe positive and negative symptoms, worse functioning and worse adherence were significantly associated with poorer insight. Less depressive symptoms (p=0.0004), less suicidality (p=0.0218), suffering from multiple illness-episodes (p<0.0001) and worse adherence (p=0.0012) at admission were identified to be significant predictors of poor insight at discharge.

CONCLUSION

The revealed predictors might function as treatment targets in order to improve insight and with it outcome of schizophrenia.

Evaluating depressive symptoms and their impact on outcome in schizophrenia applying the Calgary Depression Scale

OBJECTIVE

To examine depressive symptoms, their course during treatment, and influence on outcome.

METHOD

Weekly Calgary Depression Scale for Schizophrenia ratings were performed in 249 inpatients with schizophrenia. Early response was defined as a 20% reduction in the total score of the Positive and Negative Syndrome Scale for Schizophrenia from admission to week 2, response as a 50% reduction in the total score of the Positive and Negative Syndrome Scale for Schizophrenia (PANSS) from admission to discharge and remission according to the consensus criteria.

RESULTS

Thirty six per cent of the patients were depressed at admission, with 23% of them still being depressed at discharge. Depressed patients scored significantly higher on the PANSS negative and general psychopathology subscore, featured more impairments in subjective well-being (P < 0.0001) and functioning (P < 0.0001). They suffered from more suicidality (P = 0.0021), and had greater insight into their illness (P = 0.0105). No significant differences were found regarding early response, response, and remission.

CONCLUSION

Patients with depressive symptoms should be monitored closely, given the burden of negative symptoms, their impairments in well-being and functioning and the threat of suicidality.

Dental age estimation based on third molar eruption in First Nation people of Canada

Forensic age estimation of living subjects has become an increasing focus of interest in modern society. One main criterion for dental age estimation in the relevant age group is the evaluation of third molar eruption. The importance of ethnic variation in dental development requires population specific data for dental age evaluation. In the present study, we determined the stages of third molar eruption in 347 female and 258 male First Nations people of Canada aged 11 to 29 years based on radiological evidence from 605 conventional orthopantomograms. The results presented here provide data on the age of alveolar, gingival, and complete eruption of the third molars in the occlusal plane that can be used for forensic estimation of the minimum and most probable ages of investigated individuals.

A critical analysis and discussion of the appropriateness of the schizophrenia consensus remission criteria in clinical pharmaceutical trials

BACKGROUND

The aim of this paper is to apply the proposed consensus remission criteria to an acutely ill inpatient sample at admission and evaluate their adaptability in this patient population and pharmaceutical trials.

METHODS

The Remission in Schizophrenia Working Group's consensus criteria were applied to 272 acutely ill schizophrenia patients. Patients were examined using the PANSS, HAMD, UKU and SWN-K total scales at admission as well as the GAF, SOFAS and the Strauss-Carpenter Prognostic Scale. Sociodemographic and clinical baseline variables were assessed using a standardized documentation system.

RESULTS

33 patients (12%) fulfilled the symptom severity component of the proposed remission criteria already at baseline. Almost no significant differences were found when comparing patients with achieved and failed symptom severity component that would explain the hospitalization of the patients with achieved criteria despite their apparently mild psychopathological symptoms. The only explainable difference was that patients with an achieved symptom severity component had received significantly more antipsychotics and had suffered from significantly more life events before admission.

CONCLUSION

The present results raise the question whether the symptom severity threshold is adequate to identify patients in remission when applied in clinical trials.

[Adrenal tumors. Principles of diagnostics and operative treatment]

Adrenal masses are very heterogeneous and comprise benign or malignant tumors, unilateral or bilateral masses and variable endocrine activity. Because of these attributes adrenal gland masses are a clinical challenge. This article gives a summary of diagnostic steps and indications for adrenal surgery including perioperative management.

Outcome of suicidal patients with schizophrenia: results from a naturalistic study

OBJECTIVE

Purpose was to assess suicidality before and at the time of admission in patients with schizophrenia and compare outcome differences.

METHOD

Biweekly PANSS (Positive and Negative Syndrome Scale), HAMD (Hamilton Depression Rating Scale) and UKU (Udvalg for Klinske Undersogelser Side Effect Rating Scale) ratings were evaluated in 339 in-patients with schizophrenic spectrum disorders. Response was defined as an initial 20% PANSS total score reduction at discharge, remission was defined according to the proposed consensus criteria by the Remission in Schizophrenia Working Group.

RESULTS

Suicidal patients (22%) scored significantly higher on the PANSS negative subscore, PANSS insight item and HAMD total score at admission and at discharge. They developed significantly more side effects. No differences were found concerning response and remission between the two patient subgroups.

CONCLUSION

Despite receiving significantly more antidepressants the suicidal patients suffered from significantly more depressive symptoms up to discharge, yet without differing regarding response and remission.

Time course of antipsychotic treatment response in schizophrenia: results from a naturalistic study in 280 patients

OBJECTIVE

To describe the course of positive and negative symptoms during inpatient treatment and examine remission and response rates under routine clinical care conditions.

METHODS

Two hundred and eighty inpatients with schizophrenia (DSM-IV criteria) were assessed with the Positive and Negative Syndrome Scale (PANSS) at admission and at biweekly intervals until discharge from hospital. Remission was defined according to the symptom-severity component of the consensus criteria (Remission in Schizophrenia Working Group) as a rating of three or less in the relevant PANSS items at discharge, and response as a reduction of at least 20% in the PANSS total score from admission to discharge.

RESULTS

The mean duration of inpatient treatment was 54.8 days. Of the total sample, 78.5% achieved the criteria for response and 44.6% those for remission. Mean PANSS total scores decreased from 72.4 at admission to 52.5 at discharge (p<0.001). A reduction in PANSS total scores was found from visit to visit, up to week 8. The most pronounced decline was observed within the first two weeks of treatment.

CONCLUSION

Response rates were comparable to those found in efficacy studies, and remission rates were slightly higher. This may be explained by differences in the selection and the treatment of patients. Nevertheless, the findings might indicate that a complex naturalistic treatment approach is beneficial in terms of effectiveness.

Thermodynamic and structural behaviour of equimolar POPC/CnE4 (n=8, 12, 16) mixtures by sorption gravimetry, 2H NMR spectroscopy and X-ray diffraction

The hydration behaviour of equimolar mixtures of phospholipids and nonionic surfactants with different chain length was investigated by gravimetric sorption, NMR spectroscopy and X-ray diffraction. At the most hydration degrees investigated, the incorporation of nonionic surfactants in a phospholipid bilayer leads to an increase of the hydrophilicity, which can be shown by the presence of excess hydration. The increased hydrophilicity could be explained by the excavation of additional water binding sites due to the "dilution" of the dipole field of the phospholipid bilayer. Another related contribution arises from the increase of the accessible surface area due to the increase of gauche conformers that result from the steric mismatch when surfactants are incorporated into the phospholipid matrix. (2)H NMR spectroscopy was used to determine the quadrupolar splitting representing a measure of the order state of water. The swelling behaviour could be assessed by small-angle X-ray diffraction. (31)P NMR spectroscopy was applied for the assignment of phase structures to the respective hydration range.

Standardized remission criteria in schizophrenia: descriptive validity and comparability with previously used outcome measures

INTRODUCTION

Standardized consensus criteria for remission in schizophrenia were recently proposed. As yet, the validity of these criteria and their comparability with previously used outcome measures are unclear.

METHODS

The symptom-severity component of the proposed remission criteria was applied to 288 inpatients who fulfilled the ICD-10 criteria for schizophrenia. Global functioning and psychopathological symptoms were assessed using GAF, PANSS, SANS, HAM-D and CDSS.

RESULTS

When patients with symptom remission at discharge from hospitalization (n=158, 54.9%) were compared to those without symptom remission, significant differences were found with respect to the global functioning (GAF) and all observed psychopathological symptom dimensions. The percentage agreement with previously used outcome measures ranged between 52.6 and 80.0%, the kappa values between 0.120 and 0.594. A moderate accordance (kappa value: 0.495) was found with a Clinical Global Impression (CGI) severity score of three or less.

DISCUSSION

The results indicate a high descriptive validity of the symptom-severity component of the proposed remission definition. However, the new criteria differ partially from previously used outcome measures. This aspect should be considered in the interpretation of clinical trials.

A rapid mtDNA assay of 22 SNPs in one multiplex reaction increases the power of forensic testing in European Caucasians

We have developed a multiplex mitochondrial (mtDNA) assay of 21 coding region single nucleotide polymorphisms (SNPs) and one control region SNP outside hypervariable region 1 (HVR1) and hypervariable region 2 (HVR2) that can be amplified in a single reverse touchdown polymerase chain reaction. Single base extension using the SNaPshot technique is also carried out as one multiplex. Besides the nine major European haplogroups (i.e. H, I, J, K, T, U, V, W, and X), 16 additional subclades (i.e. N1, X2, X2b, U2'-4/7'-9', J/T, J1, J1c, HV, H1, H1a1, H1c, H3, H4, H6a, H7a H10) can be detected and classified into a phylogenetic mtDNA tree. By analyzing 130 Caucasoid samples from Germany, 36 different haplotypes were found resulting in a power of discrimination of 93.2%. Although 49% of all samples belonged to superhaplogroup H, the most common haplotype, i.e., haplogroup-specific SNPs plus haplogroup unspecific SNPs, had a frequency of only 18%. This assay is applicable for high-throughput mtDNA analysis and forensic mass screening. It will give additional information to the common control region sequencing of HVR1 and HVR2.

Clotted blood as sign of alcohol intoxication: a retrospective study

A total of 138 autopsies performed at the Institute of Legal Medicine of the University of Münster between 1994 and 2006 were subdivided into two groups: (1) 69 asphyxial deaths with a blood alcohol level (BAL) > 1 per thousand and (2) 69 asphyxial deaths with a BAL of 0.00 per thousand. The coagulation state in the central vessels was registered in all cases as fluid, compactly clotted or loosely clotted, and the post-mortem interval was recorded. Histology investigations were performed on the liver to analyze the incidence of hepatic fibrosis/cirrhosis. Fisher's exact test was performed to check for statistical significance. The blood was found to be clotted in 49.3% of the cases of group (1) and in 5.8% of group (2) (p < 0.01). The post-mortem interval did not have any influence on the coagulation state as observed in both groups. Liver fibrosis/cirrhosis was a rare finding detected in three cases in group 1 and in two cases in the control group 2 and, therefore, not relative to our observations. A distinctly positive BAL is often associated with heavy stages of blood coagulation as observed during autopsy. Distinctly positive alcohol concentrations have an influence on the fibrinolytic process and, hence, on the coagulation status.

[Sleep disorders in depression. Suggestions for a therapeutic approach]

Sleep disorder is one of the major symptoms in depression. It can be a risk factor, predictor, or symptom of depressive episodes. Successful therapy of sleep disorder in severely depressed patients can be a problem of its own. So far, there are few data from systematic studies. Definite treatment recommendations and strategies do not exist. The use of sleeping aids is mainly based on clinical experience and arbitrary treatment preferences. This article tries to summarize the difficulties of a rational therapeutic approach to dyssomnia in depressive patients. In addition to medical treatment, the basics of sleep hygiene should be considered. From a pharmacological point of view, sedating antidepressants, short-term add-on benzodiazepines or nonbenzodiazepines, and long-term add-on low potency neuroleptics are considered appropriate treatments. The combination with atypical sedating antipsychotics or low-dose tricyclic antidepressants may be helpful. Drugs which primarily work through serotonin and noradrenalin have negative effects on sleeping disorders since they suppress REM sleep. In contrast to that, GABAergic, antihistaminic, and anticholinergic effects are beneficial for inducing and maintaining sleep. Half-time, pharmacodynamic and pharmacokinetic effects and interactions, and influence of the drugs on reaction time and personal well-being have to be considered.

Thermotropic phase behaviour of the pseudobinary mixtures of DPPC/C12E5 and DMPC/C12E5 determined by differential scanning calorimetry and ultrasonic velocimetry

The present paper reports on the phase behaviour of the pseudobinary aqueous mixtures of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC)/pentaethylene glycol monododecyl ether (C12E5) and 1,2-dimyristoyl-sn-glycero-3-phosphocholine monohydrate (DMPC)/C12E5. Both systems exhibit a variety of mesophases, such as lamellar gel, liquid crystalline and micellar phases. The phase diagrams show peritectic and eutectic behaviours. The existence of a compound complex is established. From the phase diagrams, the temperature dependence of the solubilisation parameters is obtained. The phase diagrams, especially with respect to the solubilisation process were qualitatively explained assuming that the packing of the constituents plays a dominating role. Finally, differential scanning calorimetry and ultrasonic velocimetry are compared concerning their potentials to determine characteristics of phase transitions in pseudobinary phospholipid/surfactant mixtures.

Sudden death after isobutane sniffing: a report of two forensic cases

The intentional inhalation of a volatile substance ("sniffing") causing euphoria and hallucinations is an under-recognised form of substance abuse in children and adolescents with a high morbidity and mortality. Sudden death can be caused by cardiac arrhythmia, asphyxia or trauma. Two fatal cases of isobutane sniffing of cigarette lighter refill containing isobutane are reported. Toxicological investigations revealed the presence of isobutane in the heart blood and brain tissue of both cases (case 1: heart blood 0.1 microg/g, brain tissue 2.3 microg/g; case 2: heart blood 4.6 microg/g, brain tissue 17.4 microg/g) and the presence of its metabolite 2-methyl-2-propanol in the heart blood of both cases (0.5 and 1.8 microg/g, respectively). The histological investigations of the inner organs showed similar results in both victims. Autopsy findings, results of the histological and immunohistochemical investigations, toxicological findings and analytical procedures are discussed.

An unusual case of homicidal near drowning followed by electrocution

A young woman was found dead in a bath-tub with her facial orifices under water and current burn marks at the right big toe and at the neck near the hairline. Initial police investigations assumed an accidental electric shock due to a radio falling into the water. The forensic autopsy was followed by extensive histology and immunohistochemistry of the internal organs and skin marks. Intensive vital reactions of a near-drowning were detected that suggested a survival period of at least 20 min. Furthermore, an energy dispersive x-ray spectroscopy analysis on the current burn marks and on possible current applicators was performed, as well as reconstruction experiments with a cadaver of a pig that had been slaughtered shortly before. The results of all investigations revealed a two-step procedure with a primary near-drowning and a final current application with consecutive cardiac arrest.