Background And Purpose: The radiologic evaluation of ongoing myelination is currently limited prenatally. Novel quantitative MR imaging modalities provide relaxometric properties that are linked to myelinogenesis. In this retrospective postmortem imaging study, the capability of Synthetic MR imaging and MR fingerprinting-derived relaxometry for tracking fetal myelin development was investigated.
View Article and Find Full Text PDFIt has recently been established that polymer crystallization can preferentially place nanoparticles (NPs) into the amorphous domains of a lamellar semicrystalline morphology. The phenomenology of this process is clear: when the time for NP diffusion is shorter than the crystal growth time, then the NPs are rejected by the growing crystals and placed in the amorphous domains. However, since there is no quantitative characterization of this ordered NP state, we develop a correlation function analysis for small-angle X-ray scattering data, inspired by classical methods used for enunciating the local morphology of lamellar semicrystalline polymers.
View Article and Find Full Text PDFNearly fifty years ago Lovinger and Gryte suggested that the directional crystallization of a polymer was analogous to the quiescent isothermal crystallization experiment but at a supercooling where the crystal growth velocity was equal to the velocity of the moving front. Our experiments showed that this equivalence holds in a detailed manner at low directional velocities. To understand the underlying physics of these situations, we modeled the motion of a crystallization front in a liquid where the left side boundary is suddenly lowered below the melting point (Stefan's problem) but with the modification that the crystallization kinetics follow a version of the Avrami model.
View Article and Find Full Text PDFPurpose: To evaluate whether a deep learning model (DLM) could increase the detection sensitivity of radiologists for intracranial aneurysms on CT angiography (CTA) in aneurysmal subarachnoid hemorrhage (aSAH).
Methods: Three different DLMs were trained on CTA datasets of 68 aSAH patients with 79 aneurysms with their outputs being combined applying ensemble learning (DLM-Ens). The DLM-Ens was evaluated on an independent test set of 104 aSAH patients with 126 aneuryms (mean volume 129.
Recent experimental work has shown that polymer crystallisation can be used to "move" and organize nanoparticles (NP). As a first effort at modeling this situation, we consider the classical Stefan problem but with the modification that polymer crystallisation does not occur at a single temperature. Rather, the rate of crystallisation is proportional to its subcooling, and here we employ a form inspired by the classical Avrami model to describe this functional form.
View Article and Find Full Text PDFObjectives: To investigate whether the increased soft tissue contrast of virtual monoenergetic images (VMIs) obtained from a spectral detector computed tomography (SDCT) system improves washout assessment of arterially hyper-enhancing liver lesions.
Methods: Fifty-nine arterially hyper-enhancing lesions in 31 patients (age 65 ± 9 years, M/W 20/11) were included in this IRB-approved study. All patients underwent multi-phase SDCT for HCC screening.
Zone annealing, a directional crystallization technique originally used for the purification of semiconductors, is applied here to crystalline polymers. Tight control over the final lamellar orientation and thickness of semicrystalline polymers can be obtained by directionally solidifying the material under optimal conditions. It has previously been postulated by Lovinger and Gryte that, at steady state, the crystal growth rate of a polymer undergoing zone annealing is equal to the velocity at which the sample is drawn through the temperature gradient.
View Article and Find Full Text PDFWe previously showed that nanoparticles (NPs) could be ordered into structures by using the growth rate of polymer crystals as the control variable. In particular, for slow enough spherulitic growth fronts, the NPs grafted with amorphous polymer chains are selectively moved into the interlamellar, interfibrillar, and interspherulitic zones of a lamellar morphology, specifically going from interlamellar to interspherulitic with progressively decreasing crystal growth rates. Here, we examine the effect of NP polymer grafting density on crystallization kinetics.
View Article and Find Full Text PDFJ Forensic Leg Med
January 2020
A fatality of an 83-year-old female experiencing acute circulatory failure as a result of a type II odontoid fracture is compared with the case of an 86-year-old female who died from delayed cardiopulmonary complications due to a lower cervical spine injury. Falls on the forehead from minor height can cause odontoid fractures especially in elderly patients, hyperextension of the neck on the other hand can lead to lower cervical spine injury with prevertebral hematoma. The latter can lead to extensive hematoma of the neck, but might be difficult to diagnose by computed tomography in the living patient.
View Article and Find Full Text PDFWe report the case of a 65-year-old man who was attacked and killed by a female elephant that had previously escaped from a nearby circus. According to a witness the man was lifted up by the tusks, flung into the air and stomped upon. At autopsy the body showed signs of severe blunt force trauma and impalement, including multiple lacerations of the skin, a crushed thorax, a spinal fracture and a fractured humerus.
View Article and Find Full Text PDFThree-dimensional (3D) crime scene documentation using 3D scanners and medical imaging modalities like computed tomography (CT) and magnetic resonance imaging (MRI) are increasingly applied in forensic casework. Together with digital photography, these modalities enable comprehensive and non-invasive recording of forensically relevant information regarding injuries/pathologies inside the body and on its surface. Furthermore, it is possible to capture traces and items at crime scenes.
View Article and Find Full Text PDFPurpose: The aim of this multi-reader feasibility study was to evaluate new post-processing CT imaging tools in rib fracture assessment of forensic cases by analyzing detection time and diagnostic accuracy.
Materials And Methods: Thirty autopsy cases (20 with and 10 without rib fractures in autopsy) were randomly selected and included in this study. All cases received a native whole body CT scan prior to the autopsy procedure, which included dissection and careful evaluation of each rib.
Determination of skeletal development is a key pillar in forensic age estimation of living persons. Radiological assessment of hand bone age is widely used until the age of about 17-18 years, applying visual grading techniques to hand radiographs. This study investigated whether Greulich-Pyle (GP) and Tanner-Whitehouse (TW2) grading can be equally used for magnetic resonance imaging (MRI) data, which would offer the huge benefit of avoiding ionizing radiation.
View Article and Find Full Text PDFIn view of a potential future use for dating hemorrhage in forensic medicine the correlation of MR relaxation parameters with time was evaluated in blood samples. A systematic relationship could be valuable for using MRI for estimating the age of hemorrhage and soft tissue hematomas particularly in clinical forensic medicine. Relaxation times T1, T2, and T2(*) of venous blood samples from 6 volunteers were measured using 3T MRI regularly up to 30 days.
View Article and Find Full Text PDFObjective: Investigating the proportions of anamnestic and biochemical variables of the previous and current pregnancies for the prediction of small for gestational age (SGA) neonates in the current pregnancy.
Methods: In this observational retrospective study, 45 029 pregnancies were examined, including 3862 patients with more than one pregnancy. Odds ratios for SGA using anamnestic parameters and pregnancy-associated plasma protein A (PAPP-A) values from all pregnancies were estimated by using a logistic regression model.
External examination of the body surface with documentation of all visible findings can still be regarded as the status quo of clinical forensic injury assessment. It is obvious that internal findings cannot be detected using this technique. For obtaining such findings accessible well-established radiological techniques, such as computed tomography (CT) and magnetic resonance imaging (MRI) should be used.
View Article and Find Full Text PDFThe following work describes the development of a novel noninvasive transmucosal drug delivery system, the chitosan sponge matrix (CSM). It is composed of cationic chitosan (CS) nanoparticles (NPs) that encapsulate cisplatin (CDDP) embedded within a polymeric mucoadhesive CS matrix. CSM is designed to swell up when exposed to moisture, facilitating release of the NPs via diffusion across the matrix.
View Article and Find Full Text PDFSickle cell anemia (SCA) is a hemolytic disease characterized by the production of abnormal hemoglobin chains and distorted red blood cell morphology or sickling. "Sickle cell crisis" includes vaso-occlusive crisis, a plastic crisis, sequestration crisis, haemolytic crisis and often culminating in serious complications, organ damage and even sudden death. Post-mortem computed tomography (PMCT) findings of sickle cell disease have never been reported in literature.
View Article and Find Full Text PDFThe body of a 59 year old woman underwent postmortem computed tomography (PMCT) examination prior to forensic autopsy, using a 256 slice multidetector row computed tomography scanner. A large left tension pneumothorax detected on the PMCT was considered to be a likely cause of death and this was confirmed at autopsy. In addition there was an unsuspected PMCT finding of a probable gunshot injury traversing the right orbit, facial bones and frontal sinus.
View Article and Find Full Text PDFThe diagnosis of fatal anaphylaxis can be difficult for clinical features may not always be evident in necropsy. Therefore post mortem determination of tryptase and other blood parameters can be helpful in verifying the diagnosis. We compared post mortem tryptase, histamine and diamine oxidase (DAO) serum levels of two patients who had died after a Hymenoptera sting and one patient who died of bronchospasm during anaesthesia with data obtained from 55 control subjects who had died from other causes than anaphylaxis.
View Article and Find Full Text PDFObjective: The aim of this study was to determine whether weight force application to the lower torso can lead to impairment of inferior vena cava (IVC) and cardiovascular parameters.
Methods: Using ultrasound sonography and impedance cardiography, the effects of a weight force application of 5, 10, 15, and 25 kg to the lower torso, placed in prone position, on IVC diameter and maximal blood flow, mean artery pressure, stroke volume, heart rate, cardiac index, cardiac output, oxygen saturation (SpO(2)), and acceleration index were investigated in 6 healthy volunteers.
Results: The following parameters showed a statistically significant correlation with the amount of weight force applied: IVC diameter: r=-0.
The mitochondrial permeability transition pore is a high conductance channel whose opening leads to an increase of mitochondrial inner membrane permeability to solutes with molecular masses up to approximately 1500 Da. In this review we trace the rise of the permeability transition pore from the status of in vitro artifact to that of effector mechanism of cell death. We then cover recent results based on genetic inactivation of putative permeability transition pore components, and discuss their meaning for our understanding of pore structure.
View Article and Find Full Text PDFBiochim Biophys Acta
September 2006
Opening of the permeability transition pore (PTP), a high-conductance mitochondrial channel, causes mitochondrial dysfunction with Ca2+ deregulation, ATP depletion, release of pyridine nucleotides and of mitochondrial apoptogenic proteins. Despite major efforts, the molecular nature of the PTP remains elusive. A compound library screening led to the identification of a novel high affinity PTP inhibitor (Ro 68-3400), which labeled a approximately 32 kDa protein that was identified as isoform 1 of the voltage-dependent anion channel (VDAC1) [A.
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