RESUMEN
Traumatic brain injury (TBI) is a ubiquitous, common sequela of accidents with an annual prevalence of several million cases worldwide. In forensic pathology, structural proteins of the cellular compartments of the CNS in serum and cerebrospinal fluid (CSF) have been predominantly used so far as markers of an acute trauma reaction for the biochemical assessment of neuropathological changes after TBI. The analysis of endogenous metabolites offers an innovative approach that has not yet been considered widely in the assessment of causes and circumstances of death, for example after TBI. The present study, therefore, addresses the question whether the detection of metabolites by liquid-chromatography-mass spectrometry (LC/MS) analysis in post mortem CSF is suitable to identify TBI and to distinguish it from acute cardiovascular control fatalities (CVF). Metabolite analysis of 60 CSF samples collected during autopsies was performed using high resolution (HR)-LC/MS. Subsequent statistical and graphical evaluation as well as the calculation of a TBI/CVF quotient yielded promising results: numerous metabolites were identified that showed significant concentration differences in the post mortem CSF for lethal acute TBI (survival times up to 90 min) compared to CVF. For the first time, this forensic study provides an evaluation of a new generation of biomarkers for diagnosing TBI in the differentiation to other causes of death, here CVF, as surrogate markers for the post mortem assessment of complex neuropathological processes in the CNS ("neuroforensomics").
Asunto(s)
Biomarcadores , Lesiones Traumáticas del Encéfalo , Humanos , Lesiones Traumáticas del Encéfalo/líquido cefalorraquídeo , Lesiones Traumáticas del Encéfalo/metabolismo , Lesiones Traumáticas del Encéfalo/diagnóstico , Biomarcadores/líquido cefalorraquídeo , Masculino , Femenino , Persona de Mediana Edad , Adulto , Anciano , Cromatografía Liquida , Metabolómica/métodos , Espectrometría de Masas/métodos , Adulto Joven , Autopsia , Anciano de 80 o más AñosRESUMEN
Sepsis is one of the major threats for the survival and prognosis of patients in intensive care units. In cases where detailed clinical data and monitoring is available, the diagnosis of sepsis is reliable. But when clinical data are incomplete or missing and sepsis is only suspected based on the autopsy results, the picture is often equivocal. This report describes the gross pathological findings obtained from the autopsy of a 48-year-old woman with Crohn's disease after surgical intervention. Macroscopically, we found intestinal perforation and signs of peritonitis. Histologically, the pulmonary/bronchial arteries were lined with E-selectin (CD 62E)-positive endothelial cells, which are an established postmortem histological marker of sepsis. We extended our investigations to the cerebral cortex and subcortical medullary layer. The endothelium of the cortical vessels and those in the cerebral medullary layer were likewise immunopositive for E-selectin. Furthermore, numerous TMEM119-positive, highly ramified microglial cell profiles were found in the grey and white matter. Microglial cells were lining the vascular profiles. In addition, TMEM119-positive microglial profiles were abundant in the cerebrospinal fluid (CSF). Multiorgan E-selectin positivity of the vascular endothelia provides further evidence for the postmortem diagnosis of sepsis.
Asunto(s)
Selectina E , Sepsis , Femenino , Humanos , Persona de Mediana Edad , Selectina E/metabolismo , Células Endoteliales/metabolismo , Endotelio Vascular/metabolismoRESUMEN
Routine coronal paraffin-sections through the dorsal frontal and parieto-occipital cortex of a total of sixty cases with divergent causes of death were immunohistochemically (IHC) stained with an antibody against TMEM119. Samples of cerebrospinal fluid (CSF) of the same cases were collected by suboccipital needle-puncture, subjected to centrifugation and processed as cytospin preparations stained with TMEM119. Both, cytospin preparations and sections were subjected to computer-assisted density measurements. The density of microglial TMEM119-positive cortical profiles correlated with that of cytospin results and with the density of TMEM119-positive microglial profiles in the medullary layer. There was no statistically significant correlation between the density of medullary TMEM119-positive profiles and the cytospin data. Cortical microglial cells were primarily encountered in supragranular layers I, II, and IIIa and in infragranular layers V and VI, the region of U-fibers and in circumscribed foci or spread in a diffuse manner and high density over the white matter. We have evidence that cortical microglia directly migrate into CSF without using the glympathic pathway. Microglia in the medullary layer shows a strong affinity to the adventitia of deep vessels in the myelin layer. Selected rapidly fatal cases including myocardial infarcts and drowning let us conclude that microglia in cortex and myelin layer can react rapidly and its reaction and migration is subject to pre-existing external and internal factors. Cytospin preparations proved to be a simple tool to analyze and assess complex changes in the CNS after rapid fatal damage. There is no statistically significant correlation between cytospin and postmortem interval. Therefore, the quantitative analyses of postmortem cytospins obviously reflect the neuropathology of the complete central nervous system. Cytospins provide forensic pathologists a rather simple and easy to perform method for the global assessment of CNS affliction.
Asunto(s)
Microglía , Sustancia Blanca , Biomarcadores/metabolismo , Humanos , Proteínas de la Membrana , Microglía/metabolismo , Parafina/metabolismo , Punción Espinal , Sustancia Blanca/metabolismoRESUMEN
In order to evaluate driving abilities of each traffic participant, standardised and objective measurement methods are needed. The applicability and value of infrared pupillography as an objective measurement method to indicate possible influence of central nervous acting substances has been demonstrated in former publications. Healthy test subjects (n = 41), as well as persons who were under the influence of drugs and/or medication (n = 105), were exposed to different light stimuli using infrared technology in order to demonstrate the relevance of specific parameters of the pupillary light reflex (PLR) in the field of traffic medicine. Based on former reported results, the statistical examination was extended to further parameters of the PLR, which again confirmed the high value of infrared pupillography as a reliable indicator of previous consumption of drugs and/or medication.
Asunto(s)
Fármacos del Sistema Nervioso Central/farmacología , Conducir bajo la Influencia , Reflejo Pupilar , Detección de Abuso de Sustancias/métodos , Adulto , Estudios de Casos y Controles , Fármacos del Sistema Nervioso Central/sangre , Toxicología Forense , Humanos , Rayos Infrarrojos , Modelos Estadísticos , Detección de Abuso de Sustancias/instrumentaciónRESUMEN
New measurements of vaporization enthalpies for 15 1:1 ionic liquids are performed by using a quartz-crystal microbalance. Collection and analysis of 33 available crystal structures of organic salts, which comprise 13 different cations and 12 anions, is performed. Their dissociation lattice enthalpies are calculated by a combination of experimental and quantum chemical quantities and are divided into the relaxation and Coulomb components to give an insight into elusive short-range interaction enthalpies. An empirical equation is developed, based on interaction-specific Hirshfeld surfaces and solvation enthalpies, which enables the estimation of the lattice enthalpy by using only the crystal-structure data.
RESUMEN
The molecular interaction potentials, including S (dipolarity/polarizability), A (hydrogen bonding acidity), and B (hydrogen bonding basicity), of anions are experimentally determined using multi-functionalized stationary phases in high-performance liquid chromatography (HPLC) systems. We employ three different multi-functionalized stationary phase columns (Obelisc R, Obelisc N, and Acclaim Trinity-P1) combined with two ingredients, namely, acetonitrile (ACN) and methanol (MeOH). These conditions can cause neutral, cationic, and anionic compounds to be retained. By using the retention characteristics of calibration compounds, including cations, anions, and neutral compounds, system parameters including the ionic interaction terms (zc Zc , za Za ) are evaluated using multiple linear regression, resulting in a standard deviation (SD) of 0.090-0.158 log units. Based on the system parameters and retention characteristics of the anions of interest, their molecular interaction potentials are characterized on the same scale for neutral and cationic molecules. Furthermore, to verify the determined molecular interaction potentials, we predict anion hydrophobicity. The results show that the determined S, A, and B, together with the computable descriptors E (excess molar refraction) and V (McGowan volume), can predict anion hydrophobicity with R(2) =0.982 and SD=0.167 (dimensionless).
RESUMEN
We show for the first time that a phenomenological, augmented volume-based thermodynamics (aVBT) model is capable to predict the critical micelle concentrations of ionic surfactants, including ionic liquids, with added salts. The model also adjusts for the type of salt added by including its molecular volume, which might form a connection to the Hofmeister effect. The other physico-chemically relevant quantities included in the model include surface area and solvation enthalpies.
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We sought to determine the effect of postmortem ventilation in combination with a suction pump in cases showing penetrating trauma to the chest with haemo- and/or pneumothorax, for better evaluation of the lungs in postmortem computed tomography (PMCT). The study included 6 subjects (1 female, 5 male; age 32-67years) with a penetrating gunshot or stab wound to the chest and consecutive pneumo- and/or haemothorax. The pneumo- and haemothorax were evacuated by a suction pump, and postmortem ventilation was applied using a home care ventilator. PMCT images with and without postmortem ventilation were compared, as well as the autopsy results. In three cases haemo- and pneumothorax was clearly reduced. Postmortem ventilation led to distinct re-expansion of the lungs in two cases, and to re-expansion of single lung lobes in two cases with shotgun injuries. No visible effect was seen in the remaining two cases, because of extensive destruction of lung tissue and blood aspiration. In two cases the injuries sustained in the individual lung lobes were successfully located during postmortem ventilation. The bullet channel was apparent in one case; in another case, injury of the pericardium became visible by generating pneumopericardium. The present method is capable of improving evaluation of the postmortem lung in the presence of single stab or gunshot wounds and if there is no severe destruction of the respiratory system and aspiration. Forensic autopsy should still be considered as the gold standard, although in some cases the present method might be helpful, especially where no autopsy is required.
Asunto(s)
Presión de las Vías Aéreas Positiva Contínua/métodos , Patologia Forense/métodos , Pulmón/patología , Heridas por Arma de Fuego/patología , Heridas Punzantes/patología , Adulto , Anciano , Presión de las Vías Aéreas Positiva Contínua/instrumentación , Femenino , Patologia Forense/instrumentación , Hemotórax/diagnóstico por imagen , Humanos , Pulmón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Neumotórax/diagnóstico por imagen , Radiografía Torácica/métodos , Traumatismos Torácicos/diagnóstico por imagen , Traumatismos Torácicos/etiología , Traumatismos Torácicos/patología , Tomografía Computarizada por Rayos X , Ventiladores Mecánicos , Heridas por Arma de Fuego/diagnóstico por imagen , Heridas Punzantes/diagnóstico por imagenRESUMEN
It is well known that the amorphous state can greatly enhance the bioavailability of drugs. However, comparatively few compounds form either liquids at room temperature or glasses above it. We present qualitative insights as to why some molecules would form glasses instead of crystals and a fast, straightforward, physically well founded, and nonproprietary method to calculate the expected glass transition temperature before the synthesis of a new drug. This way, a selection of drug candidates can be screened for one that has a high tendency to vitrify and a preferably low temperature of this transition. The new method works reliably for a great span of possible molecules, encompassing well-known drugs, nutrients, and a multitude of other technically interesting compounds.
Asunto(s)
Preparaciones Farmacéuticas/química , Temperatura de Transición , Vitrificación , Análisis por Conglomerados , Simulación por Computador , Cristalización , Modelos Químicos , Análisis MultivarianteRESUMEN
Postmortem imaging has gained prominence in the field of forensic pathology. Even with experience in this procedure, difficulties arise in evaluating pathologies of the postmortem lung. The effect of postmortem ventilation with applied pressures of 10, 20, 30 and 40 mbar was evaluated in 10 corpses using simultaneous postmortem computed tomography (pmCT) scans. Ventilation was performed via a continuous positive airway pressure mask (n=5), an endotracheal tube (n=4) and a laryngeal mask (n=1) using a portable home care ventilator. The lung volumes were measured and evaluated by a segmentation technique based on reconstructed CT data. The resulting changes to the lungs were analyzed. Postmortem ventilation at 40 mbar induced a significant (p<0.05) unfolding of the lungs, with a mean volume increase of 1.32 l. Small pathologies of the lung such as scarring and pulmonary nodules as well as emphysema were revealed, while inner livores were reduced. Even though lower ventilation pressures resulted in a significant (p<0.05) volume increase, pathologies were best evaluated when a pressure of 40 mbar was applied, due to the greater reduction of the inner livores. With the ventilation-induced expansion of the lungs, a decrease in the heart diameter and gaseous distension of the stomach was recognized. In conclusion, postmortem ventilation is a feasible method for improving evaluation of the lungs and detection of small lung pathologies. This is because of the volume increase in the air-filled portions of the lung and reduced appearance of inner livores.
Asunto(s)
Autopsia/métodos , Patologia Forense/métodos , Pulmón/patología , Presión de las Vías Aéreas Positiva Contínua/métodos , Femenino , Humanos , Masculino , Tomografía Computarizada por Rayos X/métodos , Ventiladores MecánicosRESUMEN
In order to understand molecular interaction potentials of 30 cations of ionic liquids (ILs), the well-known linear free energy relationship concept (LFER) was applied. The LFER descriptors for the excess molar refractivity and the molar volume were calculated in silico and for hydrogen-bonding acidity and basicity, and the polarizability/dipolarity of IL cations were experimentally determined through high performance liquid chromatography (HPLC) measurements. For the study, three different columns (RP-select B, Cyan, and Diol) and buffered mobile phases, based on two organic solvents acetonitrile (ACN) and methanol (MeOH), were selectively combined to the HPLC separation systems RP-select B-ACN, RP-select B-MeOH, Cyan-MeOH, Diol-ACN, and Diol-MeOH. By measuring the retention factors of 45 neutral calibration compounds and calculating LFER descriptors of three cations in the HPLC systems, the system parameters, including an ionic z coefficient, were determined. Conversely, the LFER descriptors of 30 ionic liquid cations were determined, based on the parameters of five systems and their retention factors in the HPLC systems. The results showed that the type of head group, alkyl chain length and further substituents of the cation have a significant influence on the dipolarity/polarizability and the hydrogen-bonding acidity, and functionalized groups (hydroxyl, ether, and dimethylamino) lead to hydrogen-bonding basicity of the cation. The characterization of cationic LFER descriptors opens up the chance for a more quantitative understanding of molecular interaction potentials and physicochemical properties of ILs.
RESUMEN
An investigation of the melting points of 520 organic 1:1 salts is presented with the aim of developing a universal, simple, physically well-founded prediction scheme. The general reliability and reproducibility of the recorded experimental data are discussed with respect to purity, phase behavior, disorder and thermal history of a given substance. Additionally, mistakes, systematic errors, or lack of conventions can lead to considerable differences in the experimental measurements. A rough error bar for the reproducibility of the melting points of organic salts of ±5 to ±15 °C can be assigned. With this restraint, we developed two simple, semiempirical, five- and nine-parameter schemes with easy-to-calculate quantities. With these, we could predict the melting temperature of a given organic salt in the temperature range of -25 to +300 °C with an average error of 33.5 °C and a relative error of 9.3%. All calculated quantities are assessed with the help of conventional DFT, COSMO and COSMO-RS calculations, and are currently implemented into the IL-Prop module of the upcoming version of COSMOtherm. These prediction schemes are suitable for high-throughput computational screening of substances in the context of "computer-aided synthesis". Therefore, they are valuable tools to find a compound with a suitable melting point before its first synthesis.
Asunto(s)
Modelos Químicos , Compuestos Orgánicos/química , Temperatura de Transición , Entropía , Cristales Líquidos/química , Estructura Molecular , Transición de Fase , Valor Predictivo de las Pruebas , Presión , Solventes/química , Relación Estructura-ActividadRESUMEN
We present the full enthalpic phase transition cycle for ionic liquids (ILs) as examples of non-classical salts. The cycle was closed for the lattice, solvation, dissociation, and vaporization enthalpies of 30 different ILs, relying on as much experimental data as was available. High-quality dissociation enthalpies were calculated at the G3 MP2 level. From the cycle, we could establish, for the first time, the lattice and solvation enthalpies of ILs with imidazolium ions. For vaporization, lattice, and dissociation enthalpies, we also developed new prediction methods in the course of our investigations. Here, as only single-ion values need to be calculated and the tedious optimization of an ion pair can be circumvented, the computational time is short. For the vaporization enthalpy, a very simple approach was found, using a surface term and the calculated enthalpic correction to the total gas-phase energy. For the lattice enthalpy, the most important constituent proved to be the calculated conductor-like screening model (COSMO) solvation enthalpy in the ideal electric conductor. A similar model was developed for the dissociation enthalpy. According to our assessment, the typical error of the lattice enthalpy would be 9.4 kJ mol(-1), which is less than half the deviation we get when using the (optimized) Kapustinskii equation or the recent volume-based thermodynamics (VBT) theory. In contrast, the non-optimized VBT formula gives lattice enthalpies 20 to 140â kJ mol(-1) lower than the ones we assessed in the cycle, because of the insufficient description of dispersive interactions. Our findings show that quantum-chemical calculations can greatly improve the VBT approaches, which were parameterized for simple, inorganic salts with ideally point-shaped charges. In conclusion, we suggest the term "augmented VBT", or "aVBT", to describe this kind of theoretical approach.
RESUMEN
In this article, we present evolutionary models to predict the octanol-water partition coefficients (log P), water solubilities, and critical micelle concentrations (CMCs) of ionic liquids (ILs), as well as the anionic activity coefficients and hydrophobicities in pure water and octanol-water. They are based on a polyparameter linear free energy relationship (LFER) using measured and/or DFT-calculated LFER parameters: hydrogen-bonding acidity (A), hydrogen-bonding basicity (B), polarizability/dipolarity (S), excess molar refraction (E), and McGowan volume (V) of IL ions. With both calculated or experimental LFER descriptors of IL ions, the physicochemical parameters were predicted with an errors of 0.182-0.217 for the octanol-water partition coefficient and 0.131-0.166 logarithmic units for the water solubility. Because experimentally determined solute parameters of anions are not currently available, the CMC, anionic activity coefficient, and hydrophobicity were predicted with quantum-chemical methods with R(2) values of at least 0.99, as well as errors below 0.168 logarithmic units. These new approaches will facilitate the assessment of the technical applicability and environmental fate of ionic compounds even before their synthesis.
RESUMEN
Blood aspiration is a significant forensic finding. In this study, we examined the value of postmortem computed tomography (CT) imaging in evaluating findings of blood aspiration. We selected 37 cases with autopsy evidence of blood in the lungs and/or in the airways previously submitted to total-body CT scanning. The CT-images were retrospectively analyzed. In one case with pulmonary blood aspiration, biopsy specimens were obtained under CT guide for histological examination. In six cases, CT detected pulmonary abnormalities suggestive of blood aspiration, not mentioned in the autopsy reports. CT reconstructions provided additional data about the distribution and extent of aspiration. In one needle-biopsied case, the pulmonary specimens showed blood in the alveoli. We suggest the use of CT imaging as a tool complementary to traditional techniques in cases of blood aspiration to avoid misdiagnosis, to guide the investigation of lung tissue, and to allow for more evidence-based inferences on the cause of death.
Asunto(s)
Sangre/diagnóstico por imagen , Aspiración Respiratoria/diagnóstico por imagen , Sistema Respiratorio/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biopsia con Aguja Fina , Niño , Preescolar , Femenino , Patologia Forense , Humanos , Masculino , Persona de Mediana Edad , Sistema Respiratorio/patología , Estudios Retrospectivos , Imagen de Cuerpo Entero , Adulto JovenRESUMEN
Varicose vein rupture is a rare cause of death, although varicosities are a common pathology. We present three cases of sudden death due to varicose vein rupture. After a review of the literature, the case circumstances and the findings of imaging examination, performed in two cases, are presented. One of them had undergone a post-mortem computed tomography angiography (PMCTA), and one a PMCTA as well as a post-mortem magnetic resonance (PMMR) imaging prior to conventional autopsy. One of the cases presented herein is, to our knowledge, the youngest known fatality due to varicose vein rupture.
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Muerte Súbita/patología , Pierna/irrigación sanguínea , Várices/patología , Adulto , Anciano de 80 o más Años , Angiografía/métodos , Autopsia , Muerte Súbita/etiología , Diagnóstico por Imagen/métodos , Femenino , Patologia Forense/métodos , Hemorragia/etiología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Rotura/complicaciones , Rotura/diagnóstico por imagen , Tomografía Computarizada por Rayos XRESUMEN
We present a case of an individual who stabbed himself through the heart with a large knife. Post mortem computed tomography (CT) and CT-angiography were used to assess the stab channel and to reconstruct the sequence of events. After penetrating injuries to the chest, both the intra-thoracic organs and the injury causing instrument may shift (e.g. from pnemothorax) and render forensic reconstructions more challenging. This case report illustrates the potentials and the pitfalls of CT for the reconstruction of penetrating injures to the chest.
Asunto(s)
Lesiones Cardíacas/diagnóstico por imagen , Suicidio , Heridas Punzantes/diagnóstico por imagen , Autopsia/métodos , Angiografía Coronaria/métodos , Patologia Forense/métodos , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada Espiral/métodosRESUMEN
Modeling of the temperature-dependent liquid entropy of ionic liquids (ILs) with great accuracy using COSMO-RS is demonstrated. The minimum structures of eight IL ion pairs are investigated and the entropy, calculated from ion pairs, is found to differ on average only 2% from the available experimental values (119 data points). For calculations with single ions, the average error amounts to 2.6% and stronger-coordinating ions tend to give higher deviations. Additionally, the first parameterization of the standard liquid entropy for ILs is presented in the context of traditional volume-based thermodynamics (S(l)(0)=1.585 kJ mol(-1) K(-1) nm(-3)·r(m)(3)+14.09 J mol(-1) K(-1)), which sheds light on the statistical treatment of ionic interactions. The findings provide the first direct access to accurate predictions of liquid entropies of ILs, which are tedious and time-consuming to measure.
RESUMEN
The melting points (T(fus)) of crystalline ionic liquids are calculated from the ratio of the fusion enthalpy and entropy at the melting point where solid and liquid phases are in chemical equilibrium (DeltaG(T) = 0), and therefore, T(fus) = Delta(fus)H(T)/Delta(fus)S(T) (if T = T(fus)). We specify two variants of this method that have no need for experimental input or tedious simulations but rely on simple calculations feasible with standard quantum chemical program codes and may further be augmented by COSMO-RS. Only single ions are used as input, making the demanding calculation of ion pairs superfluous. The fusion enthalpy is obtained by the principles of volume-based thermodynamics (ion volumes as the major contributor), which may additionally be augmented by COSMO-RS interaction enthalpies for increased accuracy. The calculation of the fusion entropy largely relies on a procedure originally developed for neutral organic molecules that was extended to molecular ionic compounds. Its contributors are the site symmetry sigma and the number of torsion angles tau, which are both determined individually for the cation and the anion and are included as their geometric mean. The two methods were tested on several sets of ionic liquids (ILs) and a combination of all sets (67 ILs) that span an experimental melting temperature range of 337 degrees C. The average error of the simpler, volume-based model (only ion volumes, sigma, and tau as input) is 36.4 degrees C and that of the augmented method (using ion volumes, sigma, tau, and COSMO-RS output) is 24.5 degrees C.
RESUMEN
Although postmortem imaging has gained prominence in the field of forensic medicine, evaluation of the postmortem lung remains problematic. Specifically, differentiation of normal postmortem changes and pathological pulmonary changes is challenging and at times impossible. In this study, five corpses were ventilated using a mechanical ventilator with a pressure of 40 mbar (40.8 cm H(2)O). The ventilation was performed via an endotracheal tube, a larynx mask or a continuous positive airway pressure mask. Postmortem computed tomographic images of the lungs before and with a ventilation of 40 mbar (40.8 cm H(2)O) were evaluated and the lung volumes were measured with segmentation software. Postmortem ventilation led to a clearly visible decrease of both the density in the dependant parts of the lungs and ground glass attenuation, whereas consolidated areas remained unchanged. Furthermore, a mean increase in the lung volume of 2.10 l was seen. Pathological changes such as septal thickening or pulmonary nodules in the lung parenchyma became more detectable with postmortem ventilation. Intracorporal postmortem mechanical ventilation of the lungs appears to be an effective method for enhancing detection of small pathologies of the lung parenchyma as well as for discriminating between consolidation, ground glass attenuation and position-dependent density.