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Autopsy Material (autopsy + material)
Selected AbstractsSpinal Cord Neuronal Pathology in Multiple SclerosisBRAIN PATHOLOGY, Issue 4 2009Christopher P. Gilmore MRCP Abstract The objective of this study was to assess neuronal pathology in the spinal cord in multiple sclerosis (MS), both within myelinated and demyelinated tissue. Autopsy material was obtained from 38 MS cases and 21 controls. Transverse sections were taken from three spinal cord levels and stained using Luxol Fast Blue/Cresyl Violet and myelin protein immunohistochemistry. Measurements of neuronal number and size were made for all neurons within the anterior horns of the gray matter. Neurons were classified as motoneurons or interneurons according to size criteria. In comparison with controls, both motoneuron and interneuron number were reduced in MS cases at the upper cervical (interneuron P = 0.0549; motoneuron P = 0.0073) and upper thoracic (interneuron P = 0.0507; motoneuron P = 0.0144), but not the lumbar level. Interneuron cross-sectional area was reduced in MS cases at all levels (upper cervical, P = 0.0000; upper thoracic, P = 0.0002; lumbar, P = 0.0337). Neuronal loss appears to be predominantly related to local gray matter plaques, whereas interneuron atrophy occurs in both myelinated and demyelinated areas. [source] Molecular Neuropathology of Temporal Lobe Epilepsy: Complementary Approaches in Animal Models and Human Disease TissueEPILEPSIA, Issue 2007Michael Majores Summary:, Patients with temporal lobe epilepsies (TLE) frequently develop pharmacoresistance to antiepileptic treatment. In individuals with drug-refractory TLE, neurosurgical removal of the epileptogenic focus provides a therapy option with high potential for seizure control. Biopsy specimens from TLE patients constitute unique tissue resources to gain insights in neuropathological and molecular alterations involved in human TLE. Compared to human tissue specimens in most neurological diseases, where only autopsy material is available, the bioptic tissue samples from pharmacoresistant TLE patients open rather exceptional preconditions for molecular biological, electrophysiological as well as biochemical experimental approaches in human brain tissue, which cannot be carried out in postmortem material. Pathological changes in human TLE tissue are multiple and relate to structural and cellular reorganization of the hippocampal formation, selective neurodegeneration, and acquired changes of expression and distribution of neurotransmitter receptors and ion channels, underlying modified neuronal excitability. Nevertheless, human TLE tissue specimens have some limitations. For obvious reasons, human TLE tissue samples are only available from advanced, drug-resistant stages of the disease. However, in many patients, a transient episode of status epilepticus (SE) or febrile seizures in childhood can induce multiple structural and functional alterations that after a latency period result in a chronic epileptic condition. This latency period, also referred to as epileptogenesis, cannot be studied in human TLE specimens. TLE animal models may be particularly helpful in order to shed characterize new molecular pathomechanisms related to epileptogenesis and open novel therapeutic strategies for TLE. Here, we will discuss experimental approaches to unravel molecular,neuropathological aspects of TLE and highlight characteristics and potential of molecular studies in human and/or experimental TLE. [source] Magnetic resonance imaging as a tool to examine the neuropathology of multiple sclerosisNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 2 2004L. Bö Magnetic resonance imaging (MRI) has significantly extended the understanding of multiple sclerosis (MS), owing to its ability to sensitively depict the dynamics of the disease process in vivo. The subject of this review is the use of MRI in the post-mortem setting, with emphasis on how it may be used to improve the specimen selection process at autopsy. Lesions with active demyelination are highly interesting in the study of MS pathogenesis, but are rare in a typical autopsy material of chronic MS. The yield of MS lesions in autopsy specimen selection can be increased by the use of MRI-guided tissue sampling, as a significant proportion of abnormalities detected by post-mortem MRI are not macroscopically visible/palpable. The majority of these MRI abnormalities have been found to represent either discrete areas of microglial activation with no demyelination (so-called (p)reactive lesions), or active demyelinating MS lesions by further histopathological examination. The presence and extent of MS pathology outside of the focal demyelinated lesions is more readily appreciated by MRI-guided specimen sampling, as has been shown in the study of extensive areas of partial myelin loss in the spinal cord. A further advantage of MRI-guided specimen sampling is the ability to use three-dimensional and quantitative measures. The potential of correlating these with histopathological data may be further exploited in the future. The technical procedure for MRI-guided tissue sampling at autopsy is presented, and the limitations of the technique are discussed. [source] Homogeneity of active demyelinating lesions in established multiple sclerosisANNALS OF NEUROLOGY, Issue 1 2008Esther C. W. Breij PhD Objective Four different patterns of demyelination have been described in active demyelinating lesions of multiple sclerosis (MS) patients that were biopsied shortly after disease onset. These patterns were suggested to represent heterogeneity of the underlying pathogenesis. The aim of this study was to determine whether lesion heterogeneity also exists in an unselected collection of autopsy material from patients with established MS. Methods All MS brain tissue available in the VU Medical Center was assessed for the presence of active demyelinating lesions using magnetic resonance imaging,guided sampling and immunohistochemistry. Tissue blocks containing active demyelinating lesions were evaluated for the presence of complement and antibody deposition, oligodendrocyte apoptosis, differential loss of myelin proteins, and hypoxia-like damage using histology, immunohistochemistry, and confocal microscopy. Blocks with active demyelinating lesions were compared with blocks with active (nondemyelinating) and inactive lesions. Results Complement and antibodies were consistently associated with macrophages in areas of active demyelination. Preferential loss of myelin proteins, extensive hypoxia-like damage, and oligodendrocyte apoptosis were absent or rare. This pattern was observed in all tissue blocks containing active demyelinating lesions; lesion heterogeneity between patients was not found. Interpretation The immunopathological appearance of active demyelinating lesions in established MS is uniform. Initial heterogeneity of demyelinating lesions in the earliest phase of MS lesion formation may disappear over time as different pathways converge in one general mechanism of demyelination. Consistent presence of complement, antibodies, and Fc, receptors in phagocytic macrophages suggests that antibody- and complement-mediated myelin phagocytosis is the dominant mechanism of demyelination in established MS. Ann Neurol 2008;63:16,25 [source] Cryptococcosis,a review of 13 autopsy cases from a 54-year period in a large hospital,APMIS, Issue 3 2007P. BENE From 1952 to 2005, 13 cases of cryptococcosis confirmed by postmortem examination were diagnosed in autopsy material from the University Hospital in Hradec Králové, the Czech Republic. Histologically, Cryptococcus was found in multiple organs (brain and spinal cord, lungs, lymph nodes, spleen, bone marrow, liver, kidneys and adrenal glands). The lungs and CNS were the organs most often involved. Only in two cases was the diagnosis of cryptococcal infection established during the patient's lifetime, in both presenting clinically as meningitis, with positive result of CSF cultivation. Data and issues of diagnostics and treatment of cryptococcosis are discussed. [source] Anatomic site evaluation of the palatal bone for temporary orthodontic anchorage devicesCLINICAL ORAL IMPLANTS RESEARCH, Issue 7 2008Heinrich Wehrbein Abstract: Objectives: The aim of the present study was to assess the micromorphologic characteristics of the palatal bone from an implantologic standpoint. Materials and Methods: The material consisted of tissue blocks of autopsy material from 22 subjects (18 males, three females) between 18 and 63 years of age. The specimens comprised the anterior median palatal region from 5 to 10 mm behind the incisive foramen. They were prepared in the transversal plane according to ground thin-section technology. The midpalatal area as well as an area of 3 mm bilateral to the midline were assessed, and a classification of quantitative palatal bone availability was developed. Results: The findings could be divided into three classes: (1) class I palatal bone consists almost of compact bone; (2) class II cortical bone layer on oral and nasal sides of palate, broad compact bone in the suture area (,3 mm), loose trabecular bone lateral to the suture area; and (3) class III cortical bone on oral and nasal side, thin compact bone in the suture area (<3 mm) and loose-structured trabecular bone lateral to the suture area. In most sections (72.7%), class I characteristics were found (16 subjects). 18.2% of sections were assigned to class II (four subjects) and only 9.1% of sections were assigned to class III (two subjects). Conclusion: These results document that in most cases a good primary stability of temporary orthodontic anchorage devices should be achieved in the midpalatal and paramedian area of the anterior palate, as the bone quantity available is high. [source] | |||||||||||||||||||