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Alturkustani M, Bahakeem B, Zhang Q, Ang LC. Different pathological processes for acute white matter lesions in multiple sclerosis. Malays J Pathol 2020; 42:187-194. [PMID: 32860370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
INTRODUCTION Multiple sclerosis (MS) has variable clinical presentations, prognoses, pathogeneses, and pathological patterns. We conducted a pathological review of acute MS-associated lesions that focused on the degree of axonal injury, myelin loss, and glial reaction to determine whether the observed demyelination was of the primary or secondary type. MATERIALS AND METHODS After searching the records for a 15-year period at the London Health Sciences Centre Pathology Department, we identified 8 cases of surgical acute lesion biopsies in which clinical MS diagnoses were made before or after the biopsy. RESULTS The white matter pathologies in these cases could be sorted into 3 morphological patterns. The first pattern, which represents typical demyelinated plaques, was observed in 4 cases and was characterised by nearly complete demyelination accompanied by variable degrees of axon preservation and axonal swelling. The second pattern was observed in 3 cases and was characterised by demyelinating lesions containing variable numbers of myelinated axons mixed with a few demyelinated axons and variable numbers of axonal swellings. The myelinated axons ranged from scattered fibres to bands of variable thickness, and the demyelination was a mixture of primary and secondary demyelination. The third pattern was observed in 1 case and was characterised by well-demarcated areas of reduced myelin staining and numerous apoptotic nuclei. Axonal staining revealed many fragmented axons with reduced myelin staining but no definitely demyelinated axons. CONCLUSIONS This report shows that the predominant pathology underlying acute MS-related lesions is not limited to demyelination but can include axonal degeneration alone or in combination with primary demyelination which reflect different pathogenesis for these acute lesions.
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Pejhan S, Siu VM, Ang LC, Del Bigio MR, Rastegar M. Differential brain region-specific expression of MeCP2 and BDNF in Rett Syndrome patients: a distinct grey-white matter variation. Neuropathol Appl Neurobiol 2020; 46:735-750. [PMID: 32246495 DOI: 10.1111/nan.12619] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 01/03/2020] [Accepted: 03/23/2020] [Indexed: 12/18/2022]
Abstract
INTRODUCTION AND OBJECTIVES Rett Syndrome (RTT) is a neurodevelopmental disorder caused by Methyl CpG Binding Protein 2 (MECP2) gene mutations. Previous studies of MeCP2 in the human brain showed variable and inconsistent mosaic-pattern immunolabelling, which has been interpreted as a reflection of activation-state variability. We aimed to study post mortem MeCP2 and BDNF (MeCP2 target) degradation and brain region-specific detection in relation to RTT pathophysiology. METHODS We investigated MeCP2 and BDNF stabilities in non-RTT human brains by immunohistochemical labelling and compared them in three brain regions of RTT and controls. RESULTS In surgically excised samples of human hippocampus and cerebellum, MeCP2 was universally detected. There was no significantly obvious difference between males and females. However, post mortem delay in autopsy samples had substantial influence on MeCP2 detection. Immunohistochemistry studies in RTT patients showed lower MeCP2 detection in glial cells of the white matter. Glial fibrillary acidic protein (GFAP) expression was also reduced in RTT brain samples without obvious change in myelin basic protein (MBP). Neurons did not show any noticeable decrease in MeCP2 detection. BDNF immunohistochemical detection showed an astroglial/endothelial pattern without noticeable difference between RTT and controls. CONCLUSIONS Our findings indicate that MeCP2 protein is widely expressed in mature human brain cells at all ages. However, our data points towards a possible white matter abnormality in RTT and highlights the importance of studying human RTT brain tissues in parallel with research on animal and cell models of RTT.
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Affiliation(s)
- S Pejhan
- Regenerative Medicine Program, and Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - V M Siu
- Division of Medical Genetics, Department of Paediatrics, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - L C Ang
- Department of Pathology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - M R Del Bigio
- Department of Pathology, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - M Rastegar
- Regenerative Medicine Program, and Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
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Abstract
UNLABELLED A member of a family with an autosomal dominant pattern of frontotemporal dementia (FTD) with a TDP-43 pathological substrate in other members and no mutations in FTD-associated genes developed behavioral variant FTD followed by Progressive Supranuclear Palsy. Autopsy revealed a pure tauopathy of PSP pattern. CONCLUSIONS The findings raise the possibility of shared pathogenic pathways and a proximal genetic abnormality between PSP and FTLD-43.
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Affiliation(s)
- A Kertesz
- a Department of Clinical Neurological Sciences , Schulich School of Medicine and Dentistry, University of Western Ontario , 39 Doncaster Ave, London , ON , N6G 2A1 , Canada
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Hallock A, Hamilton B, Ang LC, Tay KY, Meygesi JF, Fisher BJ, Watling CJ, Macdonald DR, Bauman GS. Neurocytomas: long-term experience of a single institution. Neuro Oncol 2011; 13:943-9. [PMID: 21824889 DOI: 10.1093/neuonc/nor074] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
There is a lack of studies reporting on outcomes of control and treatment toxicities for neurocytomas. A 25-year retrospective review of a tertiary center's experience with neurocytomas was completed to report on these outcomes. All cerebral neurocytoma cases (19 patients; median age, 31 years; range, 18-62 years; 18 intraventricular and 1 extraventricular) treated between 1984 and 2009 were analyzed, including central pathology and radiology reviews. Median follow-up was 104.5 months (range, 0.75-261.7 months). Primary treatment was surgery alone (n = 18 patients), followed by surgery and adjuvant radiotherapy (n = 1). The crude local control rate after surgery was 68% for all cases (cerebral neurocytomas) and 74% for central neurocytomas. Salvage therapies included further surgery (n = 4), radiation (n = 3), and chemotherapy (n = 1). Ten-year Kaplan-Meier overall and relapse-free survival rates were 82% and 62% and 81% and 57%, respectively, for all cases and for central neurocytomas only. The median overall survival and relapse-free survival were 104.5 and 79.3 months, respectively, for all cases and for central neurocytomas. Ten patients had grade 3/4 toxicity, and 1 patient had a grade 5 perioperative hemorrhage that resulted in death 23 days after surgery. Late grade 3/4 toxicities occurred in 9 patients. Three patients had permanent grade 2 motor or cognitive deficits. We provide the first report outlining toxicities and survival outcomes in a series of 19 patients. Our experience suggests that initial surgery provides durable local control rates in two-thirds of patients, with low risk for significant permanent deficits. Salvage therapy with surgery and/or radiation provides durable local control in tumors that recur after surgery.
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Affiliation(s)
- A Hallock
- Department of Oncology, University of Western Ontario, London, Ontario, Canada
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Abstract
Mefloquine, an antimalarial medication with efficacy against JC virus, was used to treat progressive multifocal leukoencephalopathy. A 54-year-old woman with sarcoidosis presented with a progressive cerebellar syndrome. MRI showed lesions affecting the right cerebellum that progressed over time to the brainstem. JC virus was found in the cerebrospinal fluid (CSF), and brain biopsy confirmed the diagnosis of progressive multifocal leukoencephalopathy. Mefloquine 1000 mg/week was initiated 6 months after symptom onset. Clinical progression stopped immediately, and JC virus became undetectable in the CSF. No clinical or imaging evidence of disease progression has occurred over 20 months of follow-up. This is the first report of successful treatment of progressive multifocal leukoencephalopathy with mefloquine.
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Affiliation(s)
- T E Gofton
- Department of Clinical Neurological Sciences, University of Western Ontario, London, Ontario, Canada
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Fang L, Deng Z, Shatseva T, Yang J, Peng C, Du WW, Yee AJ, Ang LC, He C, Shan SW, Yang BB. MicroRNA miR-93 promotes tumor growth and angiogenesis by targeting integrin-β8. Oncogene 2010; 30:806-21. [PMID: 20956944 DOI: 10.1038/onc.2010.465] [Citation(s) in RCA: 247] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
It has been reported that the miR-106b∼25 cluster, a paralog of the miR-17∼92 cluster, possesses oncogenic activities. However, the precise role of each microRNA (miRNA) in the miR-106b∼25 cluster is not yet known. In this study, we examined the function of miR-93, one of the microRNAs within the miR-106b∼25 cluster, in angiogenesis and tumor formation. We found that miR-93 enhanced cell survival, promoted sphere formation and augmented tumor growth. Most strikingly, when miR-93-overexpressing U87 cells were co-cultured with endothelial cells, they supported endothelial cell spreading, growth, migration and tube formation. In vivo studies revealed that miR-93-expressing cells induced blood vessel formation, allowing blood vessels to extend to tumor tissues in high densities. Angiogenesis promoted by miR-93 in return facilitated cell survival, resulting in enhanced tumor growth. We further showed that integrin-β8 is a target of miR-93. Higher levels of integrin-β8 are associated with cell death in tumor mass and in human glioblastoma. Silencing of integrin-β8 expression using small interfering RNA promoted cell proliferation, whereas ectopic expression of integrin-β8 decreased cell growth. These findings showed that miR-93 promotes tumor growth and angiogenesis by suppressing, at least in part, integrin-β8 expression. Our results suggest that inhibition of miR-93 function may be a feasible approach to suppress angiogenesis and tumor growth.
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Affiliation(s)
- L Fang
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
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Midha R, Munro CA, Ang LC. End-Organ reinnervation does not prevent axonal degeneration in nerve allografts following immunosuppression withdrawal. Restor Neurol Neurosci 2003; 13:163-72. [PMID: 12671277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
Previous work indicated that appropriate end-organ reinnervation fails to influence axonal degeneration in nerve allografts following immunosuppression withdrawal. In the present study, we examined if differences existed in axonal degeneration when axons regenerated across nerve allografts are allowed or completely denied end-organ reinnervation. Two ACI rat nerve allografts (3 cm long) were sutured into gaps created in both peroneal nerves in Lewis rats. In the right leg, the distal end of the graft was connected to the distal host nerve stump to allow end-organ reinnervation. In the left leg, the distal end was turned back and double ligated (unconnected) to prevent end-organ reinnervation. Rats received Cyclosporin A daily for 12 weeks to allow for regeneration and were sacrificed at 16 (n = 5) or 18 (n = 5) weeks following engraftment to assess axonal degeneration following immunosuppression withdrawal. Five Lewis rats receiving autografts served as control and were sacrificed at 12 weeks. Morphometric analysis was performed. In the control group (autografts) the cross-sectional area of and the number of myelinated fibres in the unconnected grafts was double that of the connected grafts, suggesting a sprouting effect. There was a tenfold reduction in the mean number of fibres at weeks 16 and 18 in the allografts compared to controls, without any significant differences in the connected versus unconnected sides. End-organ reinnervation decreases sprouting of axons within the graft but does not protect axons from degeneration following immunosuppression withdrawal.
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Affiliation(s)
- R Midha
- Division of Neurosurgery and the Trauma Research Program, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada.
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Abstract
OBJECTIVE AND IMPORTANCE We report the first case in the literature of cervical myelopathy caused by progressive cord compression as a result of epithelioid hemangioendothelioma of the cervical vertebra. CLINICAL PRESENTATION A 58-year-old man presented with progressive cervical myelopathy. Imaging revealed a vascular, expansile lesion of contiguous cervical vertebrae causing cord compression. The surgical pathology revealed epithelioid hemangioendothelioma, a rare tumor not previously reported to present in such a fashion. INTERVENTION Preoperative embolization and a two-stage anterior and posterior surgical decompression and fusion procedure were performed. The high vascularity of this lesion makes surgery a formidable surgical challenge. Adjuvant radiotherapy was administered to the residual tumor because of its potential for low-grade malignancy. CONCLUSION The diagnosis relied on accurate histopathological assessment. The general principles of achieving cord decompression and tumor control are important. The literature on epithelioid hemangioendothelioma involving the spine is reviewed, and the tumor biology and the role of adjuvant therapy are discussed.
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Affiliation(s)
- J W Brennan
- Department of Surgery, Sunnybrook and Women's College Health Sciences Centre, University of Toronto, Ontario, Canada
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Affiliation(s)
- C Marras
- Toronto Western Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada
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Wu Y, Zhang Y, Cao L, Chen L, Lee V, Zheng PS, Kiani C, Adams ME, Ang LC, Paiwand F, Yang BB. Identification of the motif in versican G3 domain that plays a dominant-negative effect on astrocytoma cell proliferation through inhibiting versican secretion and binding. J Biol Chem 2001; 276:14178-86. [PMID: 11297534 DOI: 10.1074/jbc.m100618200] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
This study was designed to investigate the mechanisms by which mutant versican constructs play a dominant-negative effect on astrocytoma cell proliferation. Although a mini-versican or a versican G3 construct promoted growth of U87 astrocytoma cells, a mini-versican lacking epidermal growth factor (EGF) motifs (versicanDeltaEGF) and a G3 mutant (G3DeltaEGF) exerted a dominant-negative effect on cell proliferation. G3DeltaEGF-transfected cells formed smaller colonies, arrested cell cycle at G(1) phase, inhibited expression of cell cycle proteins cdk4 and cyclin D1, and contained multiple nucleoli. In cell surface binding assays, G3 products expressed in COS-7 cells and bacteria bound to U87 cell surface. G3DeltaEGF products exhibited decreased binding activity, but higher levels of G3DeltaEGF products were able to inhibit the binding of G3 to the cell surface. G3DeltaEGF expression inhibited secretion of endogenous versican in astrocytoma cells and also inhibited the secretion of mini-versican in COS-7 cells co-transfected with the mini-versican and G3DeltaEGF constructs. The effect seems to depend on the expression efficiency of G3DeltaEGF, and it occurred via the carbohydrate recognition domain.
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Affiliation(s)
- Y Wu
- Sunnybrook & Women's College Health Sciences Centre and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario M4N 3M5, Canada
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Abstract
OBJECT Rejection of nerve allografts and loss of regenerated host axons after withdrawal of immunosuppressive therapy poses an ongoing challenge in peripheral nerve repair. The present report is of a blinded prospective controlled study in which an established rat model of nerve allotransplantation is used to examine the effect of fiber type on survival and degeneration of nerve allografts after discontinuation of immunosuppression. The authors hypothesized that sensory axons will selectively resist a rejection response, whereas motor axons will degenerate. METHODS Four-centimeter nerve segments from ACI rats were grafted into peroneal and sural (mixed) or saphenous (sensory) nerve gaps in Lewis rats. In some rats, L4-6 dorsal root ganglia were ablated before grafting, creating pure motor sural and peroneal nerves. All rats received 12 weeks of immunosuppressive therapy to support nerve regeneration into allografts. Immunosuppression with cyclosporin was then withdrawn. At planned death (12-18 weeks postsurgery), graft tissue was subjected to histomorphometric analysis for evaluation of axon survival and loss. Graft rejection led to loss of all axons in approximately 60% of the allograft segments. The mixed nerve group was most prone to complete rejection, with significantly lowered axon counts at Weeks 16 and 18 compared with the Week 12 baseline. Axons from the sensory nerve were least likely to degenerate. The pure motor nerve group axons demonstrated intermediate sensitivity, with a selective loss of larger axons at Week 16 and a significant decrease in axon counts from the Week 12 baseline at Week 18. CONCLUSIONS Whereas the majority of axons are lost after withdrawal of immunosuppressive therapy from nerve allografts, there is a selective survival of axons from cutaneous sensory nerves and smaller-diameter motor fibers. The biological and molecular mechanisms that make some axons impervious to injury remain to be determined.
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Affiliation(s)
- R Midha
- Department of Surgery, Sunnybrook and Women 's College Health Sciences Centre, University of Toronto, Ontario, Canada.
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Sherar MD, Moriarty JA, Kolios MC, Chen JC, Peters RD, Ang LC, Hinks RS, Henkelman RM, Bronskill MJ, Kucharcyk W. Comparison of thermal damage calculated using magnetic resonance thermometry, with magnetic resonance imaging post-treatment and histology, after interstitial microwave thermal therapy of rabbit brain. Phys Med Biol 2000; 45:3563-76. [PMID: 11131184 DOI: 10.1088/0031-9155/45/12/304] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Clinical application of high-temperature thermal therapy as a treatment for solid tumours requires an accurate and close to real-time method for assessing tissue damage. Imaging methods that detect structural changes during heating may underestimate the extent of thermal damage. This is due to the occurrence of delayed damage manifested at tissue locations exposed to temperatures lower than those required to cause immediate structural changes. An alternative approach is to measure temperature and then calculate the expected damage based on the temperature history at each tissue location. Magnetic resonance (MR) imaging methods now allow temperature maps of the target and surrounding tissues to be generated in almost real-time. The aim of this work was to evaluate whether thermal damage zones calculated on the basis of MR thermometry maps measured during heating correspond to actual tissue damage as measured after treatment by histological methods and MR imaging. Four male rabbits were treated with high-temperature thermal therapy delivered in the brain by a single microwave antenna operating at 915 MHz. MR scanning was performed before, during and after treatment in a 1.5 T whole-body scanner. Temperature maps were produced using the proton resonance frequency (PRF) shift method of MR thermometry. In addition, conventional T1-weighted and T2-weighted spin-echo images were acquired after treatment. Thermal damage zones corresponding to cell death, microvascular blood flow stasis and protein coagulation were calculated using an Arrhenius analysis of the MR temperature/time course data. The calculated zones were compared with the lesions seen on histopathological examination of the brains which were removed within 6-8 h of treatment. The results showed that calculated damage zones based on MR thermometry agreed well with areas of damage as assessed using histology after heating was completed. The data suggest that real-time calculations of final expected thermal damage based on an Arrhenius analysis of MR temperature data may provide a useful method of real-time monitoring of thermal therapy when combined with conventional T2-weighted images taken after treatment.
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Affiliation(s)
- M D Sherar
- Ontario Cancer Institute/Princess Margaret Hospital, University of Toronto, Canada
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Stein M, Bell MJ, Ang LC. Hydroxychloroquine neuromyotoxicity. J Rheumatol 2000; 27:2927-31. [PMID: 11128688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Hydroxychloroquine (HCQ) is commonly prescribed for treatment of inflammatory arthritis. The most frequently observed serious side effect is retinal toxicity; however, case reports have described HCQ induced neuromyotoxicity. We describe a case of HCQ neuromyotoxicity and a literature review from 1965 to September 1998 using Medline and Embase. Including our patient, there are 10 reported cases of HCQ neuromyotoxicity. Muscle biopsy consistently reveals curvilinear bodies and muscle fiber atrophy with vacuolar changes. Most cases manifest as insidious onset proximal myopathy that may be associated with peripheral neuropathy and cardiac myotoxicity. Resolution of symptoms is slow after discontinuation of therapy and may be incomplete. Possible predisposing factors include Caucasian race and concomitant renal failure. Patients treated with HCQ who develop a proximal myopathy, cardiomyopathy, or neuropathy, especially in the setting of worsening renal function, should be evaluated for possible HCQ neuromyotoxicity.
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Affiliation(s)
- M Stein
- Department of Medicine, University of Toronto, Ontario, Canada
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Abstract
OBJECTIVE AND IMPORTANCE Mantle cell lymphoma is a distinct clinicopathological type of non-Hodgkin's lymphoma that often presents at an advanced stage, with systemic spread. Spinal involvement is uncommon and generally occurs as part of advanced disease or generalized relapses. Primary spinal epidural lymphoma is a rare initial manifestation of non-Hodgkin's lymphoma, and mantle cell lymphoma with initial presentation in the spinal epidural space is extremely rare, having been previously reported in only two cases. CLINICAL PRESENTATION We report a case of a 71-year-old man who presented with increasing weakness and numbness of the legs. Magnetic resonance imaging revealed a spinal epidural mass in the lumbosacral region. INTERVENTION The patient underwent a partial L4 and L5-S1 laminectomy, with incomplete resection of the mass for spinal decompression and tissue diagnosis. Mantle cell lymphoma was diagnosed in the pathological examination. CONCLUSION After radiotherapy, the disease recurred with a soft-tissue mass in the anterior maxillary area of the face. The patient underwent restaging and was treated with chemotherapy, with only a partial response. Mantle cell lymphoma with primary spinal epidural presentation is rare. This diagnosis can be established and other causes of spinal cord compression can be ruled out by obtaining tissue for proper histopathological examinations. Because of its aggressive behavior and poor prognosis, mantle cell lymphoma should be treated using a combined-modality approach.
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Affiliation(s)
- M Barnard
- Department of Anatomic Pathology, Sunnybrook and Women's College Health Sciences Centre, University of Toronto, Ontario, Canada
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Abstract
We report a case of dementia in an elderly woman with the pathological findings of Alzheimer's disease and numerous intranuclear inclusions in astrocytes and occasionally in neurons. These inclusions were seen in the cerebral cortex, limbic areas, basal ganglia, thalamus, brain stem and cerebellum. They expressed ubiquitin and were ultrastructurally composed of haphazardly arranged straight filaments. The presence of similar intranuclear inclusions in previous cases of adult-onset dementia without other neuropathological changes suggests an important link between these kind of inclusions and dementia. To our knowledge, this type of intranuclear inclusions has not been previously described in association with Alzheimer pathology.
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Affiliation(s)
- J al-Maghrabi
- Department of Anatomic Pathology, Sunnybrook and Women's College Health Science Center, University of Toronto, Canada
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Grigoriadis E, Fam AG, Starok M, Ang LC. Skeletal muscle infarction in diabetes mellitus. J Rheumatol 2000; 27:1063-8. [PMID: 10782838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
OBJECTIVE To analyze the risk factors, clinical features, and methods of diagnosis of diabetic muscle infarction (DMI). METHODS Three patients with diabetes mellitus (DM) and skeletal muscle infarction were studied, and 49 additional cases reported in the English literature (Medline database search) were reviewed. RESULTS Review of all 52 patients with DMI revealed a number of typical features: equal sex distribution; mean age 41.5 years (range 19-81 yrs); a number of risk factors [long duration of DM (mean 15.2 yrs), poor control and microvascular diabetic complications (neuropathy, retinopathy, nephropathy) (94%), and insulin dependent type I DM (77%)]; a characteristic clinical presentation with painful diffuse muscle swelling (100%); and sometimes a muscle mass (44%), predilection for quadriceps (62%), hip adductors (13%) and leg muscles (13%), elevated serum creatine phosphokinase (47%), abnormal sonograms (81%), abnormal magnetic resonance image (MRI) findings (100%), typical histopathologic findings of a muscle infarct (100%) (ultrastructural evidence of microangiography in one patient); and a tendency toward spontaneous resolution although recurrences are common (51%). CONCLUSION Skeletal muscle infarction is a rare complication of long standing, poorly controlled DM associated with multiple end organ microvascular sequelae. Increased clinical awareness is important for early recognition, particularly in a diabetic patient presenting with a painful thigh or leg swelling. MR imaging is the diagnostic study of choice, and in the appropriate clinical setting, may obviate the need for a muscle biopsy.
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Affiliation(s)
- E Grigoriadis
- Department of Medicine, Sunnybrook Health Science Centre, University of Toronto, Ontario, Canada
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Abstract
Rodent studies of nerve allografts are limited by a relatively short length of graft segment. The authors attempted to establish an outbred sheep model that would allow the study of longer, more clinically relevant nerve gaps. Using outbred ewes, two 8-cm long radial sensory nerves were grafted into gaps (5 cm) in the median nerve. Sheep received an autograft and an allograft. Four sheep were immunosuppressed with Cyclosporin A (CsA) and four were controls. Blood CsA levels greater than 1000 microg/L were obtained. Systemic immunosuppression resulted in severe opportunistic infections, and the sheep were sacrificed between 35 and 47 days following surgery. Histologically, in the autografts and CsA-treated allografts, evidence of nerve regeneration was seen. Non-immunosuppressed allografts were clearly rejected. While clear differences in the histology of experimental and control grafted nerve tissues were seen, the sheep allograft model presents considerable challenges due to immunosuppression-related infectious complications.
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Affiliation(s)
- T Matsuyama
- Department of Surgery, Sunnybrook and Women's College Health Sciences Centre, University of Toronto, Canada
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Abstract
BACKGROUND Cyclins are proteins that are expressed during the progression of a normal cell through the cell cycle. In a number of cancers, overexpression of cyclin A and cyclin B1 proteins has been reported, and in some instances the levels of expression correlated well with the grades of malignancy. The expression of cyclin A and cyclin B1 proteins in astrocytoma may be linked to the histologic grade or proliferative activities. OBJECTIVE To study the expression of cyclin A and cyclin B1 proteins in astrocytomas and correlate the labeling indices (LIs) of cyclin A and cyclin B1 with histologic grade and Ki-67 LI. DESIGN The surgical biopsy specimens from 65 adults with astrocytomas were reviewed and divided into grades based on the World Health Organization system. The paraffin sections were immunostained using primary antibodies against Ki-67, cyclin A, and cyclin B1. The LIs of these astrocytomas for the 3 different antibodies were determined by computerized image analysis. RESULTS The cyclin A LI showed good correlation with astrocytoma grade and Ki-67 LI. Both the nuclear and cytoplasmic cyclin B LIs correlated well with the tumor grade but showed poor correlation with Ki-67 LI. CONCLUSIONS This study suggests that although both cyclin A and B protein expression are related to the grade of malignancy in astrocytomas, cyclin A levels more generally reflect the proliferative state of these tumors. We also provide indirect evidence that cyclin B1 is associated with the aberrant progression through the G2-M phase checkpoint in astrocytomas.
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Affiliation(s)
- K Allan
- Department of Pathology, Sunnybrook and Women's College Health Science Center, University of Toronto, Toronto, Ontario
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Ang LC, Zhang Y, Cao L, Yang BL, Young B, Kiani C, Lee V, Allan K, Yang BB. Versican enhances locomotion of astrocytoma cells and reduces cell adhesion through its G1 domain. J Neuropathol Exp Neurol 1999; 58:597-605. [PMID: 10374750 DOI: 10.1097/00005072-199906000-00004] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Versican is a large extracellular proteoglycan and is expressed in a variety of tissues including the central nervous system. A malignant astrocytoma cell line U87 with high motility expressed a higher level of versican than another malignant astrocytoma cell line U343 with lower motility. We observed that the U87 cells were less adherent to tissue culture plates than the U343 cells. To investigate the role of versican in astrocytoma cell migration, we generated recombinant products of a mini-versican construct expressed in COS-7 cells. We found that the mini-versican products enhanced astrocytoma cell migration. Furthermore, enhanced migration was promoted by the G1 domain but not the G3 domain of versican. We introduced culture medium containing products of the mini-versican, the G1, and the G3 constructs separately into the astrocytoma cell lines U87 and U343. The mini-versican and the G1 construct, but not the G3 construct, were shown to reduce astrocytoma cell adhesion. The present data suggest that versican exerts its effect on astrocytoma cell migration and adhesion through the G1 domain.
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Affiliation(s)
- L C Ang
- Sunnybrook Health Science Centre, and Department of Laboratory Medicine and Pathobiology, University of Toronto, Canada
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Taylor MD, Perry J, Zlatescu MC, Stemmer-Rachamimov AO, Ang LC, Ino Y, Schwartz M, Becker LE, Louis DN, Cairncross JG. The hPMS2 exon 5 mutation and malignant glioma. Case report. J Neurosurg 1999; 90:946-50. [PMID: 10223463 DOI: 10.3171/jns.1999.90.5.0946] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Patients with Turcot syndrome (TS) are predisposed to colon tumors and primary brain tumors, typically glioblastomas or medulloblastomas. The authors describe a patient with TS featuring a known germline mutation of exon 5 of the hPMS2 mismatch repair gene who developed two metachronous glioblastomas, both with distinct oligodendroglial features. Molecular genetic analysis revealed allelic loss of chromosome 19q in the patient's second tumor but no allelic loss of chromosome 1p. Prominent microsatellite instability was also found in this tumor, consistent with a germline mismatch repair defect. Because this patient had an unusual underlying condition and his tumor had a unique histological appearance for TS, it was hypothesized that this genetic defect may predispose to malignant gliomas with oligodendroglial features. The authors therefore evaluated whether sporadic glioblastomas and oligodendrogliomas undergo mutations of this region of the hPMS2 gene. However, single-strand conformation polymorphism analysis of hPMS2 exon 5 failed to reveal mutations in 20 sporadic glioblastomas and 16 sporadic oligodendroglial gliomas. Thus, although it is possible that the germline hPMS2 exon 5 mutation may predispose to glioblastomas with an oligodendroglial component, the same genetic defect is not commonly involved in sporadic oligodendrogliomas or glioblastomas.
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Affiliation(s)
- M D Taylor
- Department of Medicine, University of Toronto, Ontario, Canada
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21
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Kapusta LR, Taylor M, Ang LC, Schwartz M. Cytologic diagnosis of a solitary brain metastasis from papillary carcinoma of the thyroid. A case report. Acta Cytol 1999; 43:432-4. [PMID: 10349375 DOI: 10.1159/000331094] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Papillary carcinoma of the thyroid metastasizes to the brain in rare instances. In published series and case reports of metastatic papillary thyroid carcinoma, diagnosis of central nervous system (CNS) metastases has been determined by histologic methods. We present a case of papillary carcinoma metastatic to brain diagnosed by cytologic methods. CASE A 43-year-old female, initially diagnosed at age 12 with papillary carcinoma of the thyroid metastatic to regional lymph nodes and lung, presented with head aches of increasing frequency and severity. A computed tomography scan confirmed a 1-cm nodule in the right inferior frontal lobe of the brain. For clinical reasons, the patient was followed with serial imaging for five years. At age 48 there was significant progression of the CNS disease, and the patient underwent stereotactic biopsy with drainage of cyst fluid. Cytologic examination of the cyst fluid and immunocytochemical studies confirmed the typical features of papillary thyroid carcinoma, including papillary clusters of cells with finely granular chromatin, micronucleoli, nuclear grooves and an associated psammoma body. CONCLUSION Neurocytology is a useful technique in the examination of cystic lesions of the brain and may be the sole technique for determination of diagnosis.
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Affiliation(s)
- L R Kapusta
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Sunnybrook Health Sciences Centre, North York, Ontario, Canada
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22
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Chen JM, Houle S, Ang LC, Commins D, Allan K, Nedzelski J, Rowed D. A study of vestibular schwannomas using positron emission tomography and monoclonal antibody Ki-67. Am J Otol 1998; 19:840-5. [PMID: 9831165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
OBJECTIVE This study aimed to evaluate the role of positron emission tomography (PET) as an in vivo determinant of tumor aggressiveness and growth. STUDY DESIGN The study design was a prospective pilot study. SETTING Positron emission tomography was performed at the Clarke Institute of Psychiatry. All patients were treated at the Sunnybrook Health Science Centre. Both institutions are affiliated with the University of Toronto, Toronto, Canada. PATIENTS The study consisted of five consecutive patients with vestibular schwannomas with tumor size of 1 cm or larger within the cerebellopontine angle. One was a recurrent tumor and four were primary tumors. INTERVENTIONS Preoperative PET studies were conducted using 18-fluorodeoxyglucose (FDG) as a radionuclide tracer to measure glucose metabolism within tumors. Tumors were processed and immunostained against Ki-67 nuclear antigen; their proliferative potentials were quantified based on immunoreactivity of tumor cells. MAIN OUTCOME MEASURES Tumor metabolic activity on PET was compared with that of contralateral cerebellum to arrive at an FDG index. This number was compared with clinical parameters and Ki-67 reactivity. RESULTS On PET, all tumors showed less metabolic activity than the cerebellum. The FDG uptake varied greatly between tumors independent of clinical parameters. All the tumors had a low proliferative index (<5%) with immunohistochemistry; there were quite a bit of intralesional variations in proliferative activities. CONCLUSION Large tumor size and recurrent disease did not correlate well with increased FDG uptake on PET. Similarly, they did not show increased cellular activities as expressed by Ki-67 immunostaining.
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Affiliation(s)
- J M Chen
- Department of Otolaryngology, Sunnybrook Health Science Centre, University of Toronto, Ontario, Canada
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23
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Piccardo P, Dlouhy SR, Lievens PM, Young K, Bird TD, Nochlin D, Dickson DW, Vinters HV, Zimmerman TR, Mackenzie IR, Kish SJ, Ang LC, De Carli C, Pocchiari M, Brown P, Gibbs CJ, Gajdusek DC, Bugiani O, Ironside J, Tagliavini F, Ghetti B. Phenotypic variability of Gerstmann-Sträussler-Scheinker disease is associated with prion protein heterogeneity. J Neuropathol Exp Neurol 1998; 57:979-88. [PMID: 9786248 DOI: 10.1097/00005072-199810000-00010] [Citation(s) in RCA: 164] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Gerstmann-Sträussler-Scheinker disease (GSS), a cerebello-pyramidal syndrome associated with dementia and caused by mutations in the prion protein gene (PRNP), is phenotypically heterogeneous. The molecular mechanisms responsible for such heterogeneity are unknown. Since we hypothesize that prion protein (PrP) heterogeneity may be associated with clinico-pathologic heterogeneity, the aim of this study was to analyze PrP in several GSS variants. Among the pathologic phenotypes of GSS, we recognize those without and with marked spongiform degeneration. In the latter (i.e. a subset of GSS P102L patients) we observed 3 major proteinase-K resistant PrP (PrPres) isoforms of ca. 21-30 kDa, similar to those seen in Creutzfeldt-Jakob disease. In contrast, the 21-30 kDa isoforms were not prominent in GSS variants without spongiform changes, including GSS A117V, GSS D202N, GSS Q212P, GSS Q217R, and 2 cases of GSS P102L. This suggests that spongiform changes in GSS are related to the presence of high levels of these distinct 21-30 kDa isoforms. Variable amounts of smaller, distinct PrPres isoforms of ca. 7-15 kDa were seen in all GSS variants. This suggests that GSS is characterized by the presence PrP isoforms that can be partially cleaved to low molecular weight PrPres peptides.
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Affiliation(s)
- P Piccardo
- Indiana University School of Medicine, Indianapolis 46202-5120, USA
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24
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Abstract
We examined an autopsy series of 14 children with shaken baby syndrome (SBS) who lacked skull fracture. Evidence of axonal injury was sought using immunohistochemical stains for neurofilament, 68-kDa neurofilament and beta-amyloid precursor protein (betaAPP). BetaAPP-positive axons were present in the cerebral white matter of all cases of SBS but were also present in 6 of 7 children dying of non-traumatic hypoxic ischemic encephalopathy (HIE). Swollen axons were present in 11 of 14 cases of SBS and in 6 of 7 cases of HIE. BetaAPP-positive axons were present in both groups in the midbrain and medulla. The cervical spinal cord in SBS contained betaAPP-positive axons in 7 of 11 cases; 5 of 7 contained swollen axons within the white matter tracts; in 2 immunoreactivity was localized to spinal nerve roots; in all 7 there was a predilection for staining at the glial head of the nerve root. Among cases of HIE, none showed abnormal axons or betaAPP-positive reactivity in the cervical cord white matter. We conclude that cerebral axonal injury is common in SBS, and may be due in part to hypoxic/ischemic injury. Cervical cord injury is also common, and cannot be attributed to HIE. These findings corroborate suggestions that flexion-extension injury about the cervical spinal column may be important in the pathogenesis of SBS.
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Affiliation(s)
- P Shannon
- Department of Pediatric Laboratory Medicine, Hospital For Sick Children and University of Toronto, Ontario, Canada
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Abstract
BACKGROUND Intracranial schwannoma involving the XIIth cranial nerve is rare. We report an unusual clinical presentation and pathological verification of a schwannoma, which had become haemorrhagic and necrotic, simulating acute purulent meningitis. METHODS A literature review of intracranial tumors presenting as acute purulent meningitis, with emphasis on schwannomas, was undertaken. RESULTS Few cases of hypoglossal schwannoma have been reported; the association with purulent meningitis has not been previously documented. CONCLUSION In patients presenting with sterile purulent meningitis, a necrotic tumor should be considered as a possible etiology.
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Affiliation(s)
- H C Onyiuke
- Division of Neurosurgery, Sunnybrook Health Centre, University of Toronto, Ontario, Canada
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26
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Deodhare SS, Ang LC, Bilbao JM. Isolated intracranial involvement in Rosai-Dorfman disease: a report of two cases and review of the literature. Arch Pathol Lab Med 1998; 122:161-5. [PMID: 9499360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Rosai-Dorfman disease is an idiopathic histiocytic disorder of lymph nodes and extranodal sites. Central nervous system manifestations of this disease are rare, and to our knowledge only 16 cases of intracranial involvement have been reported previously. Intracranial Rosai-Dorfman disease clinically and radiologically resembles meningioma, and histologic examination is essential for a definitive diagnosis. We report two cases of isolated, intracranial, dural-based Rosai-Dorfman disease, review the literature, and discuss the differential diagnoses of this lesion.
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Affiliation(s)
- S S Deodhare
- Department of Pathology, St Michael's Hospital, University of Toronto, Ontario, Canada
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27
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Moriarty JA, Chen JC, Purcell CM, Ang LC, Hinks RS, Peters RD, Henkelman RM, Plewes DB, Bronskill MJ, Kucharczyk W. MRI monitoring of interstitial microwave-induced heating and thermal lesions in rabbit brain in vivo. J Magn Reson Imaging 1998; 8:128-35. [PMID: 9500272 DOI: 10.1002/jmri.1880080125] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The purpose of this experiment was to use MRI to monitor microwave heating and thermal damage of brain tissue in vivo. Interstitial microwave antennas were implanted into the cerebral hemispheres of seven anesthetized rabbits. Variable power of 30 to 100 W was applied for periods of 5 to 15 minutes and tissue temperature was monitored continuously. MR images were obtained throughout the procedure at 20-second intervals, using a spoiled gradient-echo sequence, without significant artifact. Magnitude, phase, and complex difference images all demonstrated temperature-related signal changes during heating. The findings were better visualized on the phase and complex difference images. Phase difference image analysis revealed an approximately linear relationship between phase change and temperature. Post-treatment thermal lesions measured up to 2.0 cm in size on pathologic specimens and exhibited a zonal pattern on spin-echo MR images.
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Affiliation(s)
- J A Moriarty
- Department of Medical Imaging, University of Toronto, Ontario, Canada
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28
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Deme S, Ang LC, Skaf G, Rowed DW. Primary intramedullary primitive neuroectodermal tumor of the spinal cord: case report and review of the literature. Neurosurgery 1997; 41:1417-20. [PMID: 9402596 DOI: 10.1097/00006123-199712000-00040] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
OBJECTIVE AND IMPORTANCE Primary intraspinal primitive neuroectodermal tumors (PNETs) are rare. We report a case and review the literature. CLINICAL PRESENTATION A 22-year-old woman presented with rapidly progressive paraparesis and neurogenic bladder. INTERVENTION Preoperative computed tomography myelograms revealed a complete block at T12-L1, consistent with an intramedullary lesion. An urgent operation was performed with gross total tumor removal. The pathological findings were consistent with a PNET. Recurrence was noted within 10 weeks of surgery and has been somewhat responsive to chemotherapy and radiotherapy thus far. A review of the English literature shows that only 13 cases of primary intraspinal PNETs have been reported to date, and the present case is the second one in which the tumor was purely intramedullary. Most of the reported patients survived less than 2 years. CONCLUSION Primary intraspinal PNETs are rare tumors and carry a poor prognosis.
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Affiliation(s)
- S Deme
- Division of Neurosurgery, Sunnybrook Health Science Center, Toronto, Ontario, Canada
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29
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Abstract
Previous studies have shown both survival and loss of regenerated host axons within nerve allograft segments after withdrawal of Cyclosporin A (CsA) immunosuppression. We hypothesized that the nature of end-organ reinnervation may influence the response of the axon, with survival of axons for appropriate innervation vs degeneration for inappropriate innervation. The rat femoral nerve model was chosen, as it has approximately equal sensory (S) and motor (M) divisions. Four ACI rat peroneal nerve allografts were sutured in straight (right leg: MM and SS) or switched (left leg; MS and SM) orientation in each femoral nerve transection gap in each Lewis rat recipient. Rats received CsA for 8 weeks to allow end-organ reinnervation, after which immunosuppression was discontinued. Rats were killed at various times thereafter, and underwent histologic and morphometric analysis of the graft segment axons. The regenerated axon population in the allograft reflected the nerve of origin: significantly more but smaller fibers when the proximal nerve was sensory and fewer but larger fibers when the proximal nerve was motor. After CsA withdrawal, there was a marked decrease of host axons as part of an ensuing rejection episode. The overall proportional decrease of axons was similar across all nerve orientation groups and, therefore, did not appear to be influenced by the nerve of origin or by the end-organ. However, the sensory proximal groups (SS and SM) contained more mature, noninjured fibers, while the motor proximal groups (MM and MS) contained significantly more degeneration and newly regenerating axons. We conclude that the motor or sensory nerve origin of the host axon, rather than the end-organ, influences axon survival after immunosuppression cessation. It is hypothesized that sensory axons may be more resilient while motor axons are selectively vulnerable to this second injury.
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Affiliation(s)
- R Midha
- Department of Surgery, Sunnybrook Health Sciences Centre, University of Toronto, ON, Canada
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30
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Abstract
OBJECTIVE AND IMPORTANCE We describe a rare case of an extra-axial cavernoma of the cerebellopontine angle without internal auditory canal involvement and with an unusual appearance on preoperative magnetic resonance imaging (MRI). Only three cases of cerebellopontine angle cavernomas have been previously reported, and none of these reports included preoperative MRI. CLINICAL PRESENTATION A young man presented with subacute left facial hypesthesia and chronic asymmetrical sensorineural hearing loss. MRI revealed a mass, which was isointense on T1- and T2-weighted images, with evidence of hemorrhage (methemoglobin and hemosiderin). The lesion did not enhance after the injection of gadolinium. INTERVENTION The lesion was removed without difficulty by a suboccipital approach, with intraoperative electrophysiological monitoring of facial and cochlear nerves. Facial paresis cleared postoperatively. CONCLUSION The present case suggests that the appearance of cerebelopontine angle cavernomas as revealed by MRI may be similar to that of intraparenchymal cavernomas. This is in contrast to previously reported cases of extra-axial cavernomas at other sites. Evidence of hemorrhage in an extra-axial lesion revealed by MRI suggests a possible diagnosis of cavernoma.
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Affiliation(s)
- M Kim
- Department of Radiology, Sunnybrook Health Science Centre, University of Toronto, North York, Ontario, Canada
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31
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Mayers I, Hurst T, Johnson D, Cujec B, Ang LC, Thomson D, Fox JA, Blank GS, Saxena A, Richardson JS. Anti-CD18 antibodies improve cardiac function following cardiopulmonary bypass in dogs. J Crit Care 1996; 11:189-96. [PMID: 8977995 DOI: 10.1016/s0883-9441(96)90030-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
PURPOSE Cardiopulmonary bypass is associated with activation of neutrophils, which may adhere to vascular endothelium causing lung, heart, and brain injury. We tested whether blocking neutrophil adherence would improve organ function following cardiopulmonary bypass in dogs. MATERIALS AND METHODS All dogs received a standard anesthetic, and then one group (n = 6) received 2 hours of cardiopulmonary bypass followed by 4 hours of observation. A second group (n = 6) received a monoclonal antibody (6 mg/kg) to CD18, a neutrophil adherence factor, immediately before cardiopulmonary bypass. A third group (n = 6) did not receive cardiopulmonary bypass or antibody. RESULTS Using flow cytometry we found that the antibody bound essentially all neutrophil CD18 sites. All three groups had similar gas exchange and hemodynamics. Lung and heart histology results were similar between groups. By echocardiography, five animals receiving cardiopulmonary bypass alone showed regional wall abnormalities, whereas only one receiving antibody showed wall motion abnormality (P < .05). Following cardiopulmonary bypass, intracellular myocardial pH was higher (P < .05) in the antibody-treated group compared with the group that had cardiopulmonary bypass alone (7.23 +/- 0.05 v 7.07 +/- 0.07 respectively). CONCLUSION Monoclonal antibodies to CD18 can prevent the deterioration in cardiac function routinely observed following cardiopulmonary bypass.
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Affiliation(s)
- I Mayers
- Department of Medicine, University of Saskatchewan, Saskatoon, Canada
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32
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Abstract
BACKGROUND Thirty-one gliosarcomas (25 nonirradiated and 6 postirradiated tumors) were selected based on the presence of two distinctive areas: a malignant gliomatous and a sarcomatous component. In all cases, the sarcomatous component appears like fibrosarcoma or malignant fibrous histiocytoma. Two tumors showed additional areas consisting of osteochondroid differentiation. METHODS All tumors were examined using antibodies against Ulex europaeus agglutinin I (UEA), glial fibrillary acidic protein (GFAP), vimentin (VM), epithelial membrane antigen (EMA), desmin, collagen IV, alpha-1-antitrypsin (alpha-1-AT) and smooth muscle actin (SMA). RESULTS While the VM highlighted the sarcomatous areas of all tumors there were only scattered spindle cells that were GFAP-positive in the same areas. The alpha-1-AT was diffusely reactive in the sarcomatous areas in 20 cases. Focal immunoreactivity was seen with SMA (20 tumors), UEA (8 tumors), EMA (5 tumors), collagen IV (5 tumors) and desmin (4 tumors) in the nonvascular sarcomatous cells. CONCLUSIONS The range of immunophenotypical expression is likely to be a reflection of the capacity of a multipotential progenitor to undergo divergent differentiation. There is a very little morphological difference between the postirradiated and nonirradiated tumors except that a higher proportion of postirradiated tumors are immunoreactive to SMA and desmin.
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Affiliation(s)
- L C Ang
- Division of Pathology, Sunnybrook Health Science Center, Toronto, Canada
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33
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Abstract
Although metastatic spread of tumor to the lungs is common, massive pulmonary tumor emboli are very unusual. Most tumor emboli originate from epithelial-derived tumors. Only a few cases of pulmonary embolism from sarcomata have been reported. We herein describe the case of a 36-year-old woman who died suddenly due to massive pulmonary tumor emboli from a retroperitoneal malignant mesenchymoma. We believe this is the first case report of a mesenchymoma causing sudden death due to massive tumor embolism.
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Affiliation(s)
- H Rees
- Department of Pathology, Royal University Hospital, University of Saskatchewan, Canada
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34
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Abstract
Spontaneous rupture of thoracic aorta without aneurysm formation is extremely rare. A case of spontaneous rupture through an atheromatous plaque in an 82-year-old woman is reported. She presented with atypical chest pain, and chest radiography revealed no evidence of aneurysm. She died suddenly in the hospital within 24 h after admission. At autopsy, there was an intimal tear and rupture of the descending aorta through an atheromatous plaque, resulting in massive hemothorax. The previous reported cases of spontaneous aortic rupture were reviewed. The pathology of spontaneous aortic rupture are discussed with emphasis on the dating of the rupture, which may have significant medicolegal importance.
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Affiliation(s)
- T K Ma
- Department of Pathology, Sunnybrook Health Science Centre, University of Toronto, Ontario, Canada
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35
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Abstract
BACKGROUND Secondary (symptomatic) narcolepsy is rare. We report a subependymoma of the fourth ventricle associated with narcolepsy. The patient was a 50-year old woman with a long history of narcolepsy who died of colonic carcinoma with no cerebral metastasis. She was positive for HLA-DR2. At autopsy there was a tumour dorsal to the fourth ventricle which involved the midbrain tectum and rostral pons. Histologic examination of the tumour confirmed it to be a subependymoma. METHODS Review of the previous cases of secondary narcolepsy was made with particular reference to the anatomical location of the lesions. RESULTS Most of the lesions were found around the third ventricle and rostral brainstem. CONCLUSIONS Knowing the anatomical localization of the pathological changes in secondary narcolepsy could be important in improving our understanding of its pathogenesis.
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Affiliation(s)
- T K Ma
- Division of Pathology, Sunnybrook Health Science Centre, University of Toronto, Ontario, Canada
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36
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Abstract
Pontomedullary rent is a primary injury to the brainstem that may occur in high-speed accidents. We present a series of 13 autopsies with complete or partial pontomedullary rent documented over a 12-year period. Of the 13 cases, seven had associated basal skull fractures and three had fractures of the cervical spine. In five patients, the rent was an isolated traumatic lesion of the brain. While pontomedullary rents are mostly caused by traumatic craniocervical hyperextension, some authors feel that these rents could be a form of diffuse axonal injury caused by angular acceleration of the head. In this study, two patients had documented features of diffuse axonal injury. More than one mechanism of injury could therefore be involved. Pontomedullary rents could be underdiagnosed, as partial rent is compatible with survival and, when there are no associated fractures, these tears may be attributed to artifactual damage occurring during removal of the brain at autopsy.
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Affiliation(s)
- W Ezzat
- Department of Pathology, St Paul's Hospital, University of Saskatchewan, Saskatoon, Canada
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37
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Abstract
Although much evidence has implicated polyamines in brain development and function, little information is available on these substances in human brain. We examined the influence of regional distribution and aging on putrescine, spermidine, and spermine levels in autopsied human brain. In the adult brain, concentrations of spermidine were the highest, followed by spermine and putrescine. All three polyamines showed a distinct and uneven distribution profile among the 10 examined brain areas. Spermidine levels were especially high in white matter and thalamus (20 and 9.3 nmol/mg of protein, respectively), whereas spermine concentrations were highest in cerebellar cortex (3.4 nmol/mg of protein). High levels of putrescine were observed in cerebral cortices, putamen, and hippocampus (0.7-1.2 nmol/mg or protein), with lowest levels in cerebellum and thalamus (0.3-0.5 nmol/mg of protein). No statistically significant influence of aging (1 day to 103 years; n = 57) on either putrescine or spermine levels in occipital cortex was observed. In contrast, spermidine levels increased markedly from birth, reaching maximal levels at approximately 40 years of age (+228% increase in the mean 41-year-old group vs. 6-week-old group), which were maintained up to senescence. These observations in human brain thus differ from those reported in the rodent, in which levels of all three polyamines show a pronounced postnatal reduction. Our data support the notion that polyamines may have roles in both postnatal brain development and in mature brain function.
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Affiliation(s)
- L D Morrison
- Human Neurochemical Pathology Laboratory, Clarke Institute of Psychiatry, Toronto, Ontario, Canada
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38
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Abstract
BACKGROUND Gliosarcoma is an uncommon malignant brain tumor with mixed glial and mesenchymal elements. Experience is limited to case series, and pathologic data are disparate, leading to uncertainty about clinical features, management, and histogenesis. METHODS A clinicopathologic review of 32 patients with survival analysis and immunohistochemical studies was performed including glial fibrillary acidic protein analysis, alpha-1-antitrypsin (alpha-1-AT) analysis, and smooth muscle actin (SMA) analysis. RESULTS Twenty-five patients had primary gliosarcoma, whereas 7 developed gliosarcoma after irradiation for glioblastoma multiforme (GBM). Clinical features were similar to those of GBM. Most tumors were intraaxial and diffusely infiltrating by radiologic studies and at surgery. Median survival for primary gliosarcoma was 25 weeks overall, with patients who received irradiation surviving longer (46 vs. 13 weeks, P < 0.025). Gliosarcoma occurring after irradiation appeared hyperdense by computed tomography in five of seven cases, and median survival was 53 weeks. Primary gliosarcoma was a dimorphic tumor with malignant glial elements and features of malignant fibrous histiocytoma (MFH) or fibrosarcoma and one osteosarcoma. Smooth muscle actin labeled tumor vessels heavily, but in 15/25 primary cases, it extended to the surrounding spindle cells. The remaining cases appeared morphologically like MFH and tended to be positive for alpha-1-AT. Postirradiation gliosarcoma was fibrosarcomatous with positive SMA in 75% of the cases examined. CONCLUSIONS Gliosarcoma behaves clinically like GBM, and survival may be improved by cranial irradiation of selected patients. Smooth muscle actin reactivity in sarcomatous areas suggests histogenesis in some tumors from the smooth muscle within GBM, whereas others may arise via different mechanisms including differentiation from a pluripotential precursor. Transformation of the smooth muscle within GBM may have therapeutic implications for antiangiogenesis agents.
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Affiliation(s)
- J R Perry
- Division of Neurology, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
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39
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Abstract
Most of the neurons in the subcortical white matter of the adult cerebrum are remnants of the transient subplate cortex which appears during early cortical development. The peptidergic neurons in the subcortical white matter, beneath the striate cortex were examined qualitatively and qualitatively with immunohistochemistry for substance P, cholecystokinin, somatostatin and neuropeptide Y in seven control patients and eight patients with Alzheimer's disease. The different peptidergic subcortical neurons still persisted in normal aging. In Alzheimer's disease, however, the substance P- and somatostatin-immunoreactive neurons were decreased in numbers and showed degenerative changes.
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Affiliation(s)
- L C Ang
- Department of Pathology, University of Toronto, Sunnybrook Health Science Centre, North York, Ont., Canada
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40
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Abstract
The association of neuroaxonal dystrophy and osteopetrosis is reported in 2 siblings born to non-consanguineous parents. The 1st child was diagnosed as having infantile osteopetrosis shortly after delivery. A computed tomography scan of the head revealed agenesis of the corpus callosum. She died at the age of 9 months. Post-mortem examination showed pneumonia and bony sclerosis. Neuropathological examination revealed cerebral atrophy, ventricular dilation, absence of the corpus callosum, and a small hippocampus. Neuroaxonal spheroids were found in hippocampus, basal ganglia, pons, medulla, spinal cord, cranial nerves, cerebellum, and peripheral nerves. Ultrastructural examination revealed membranous cytoplasmic bodies and electron-dense granular deposits within the neuroaxonal spheroids as well as the soma of neurons. The 2nd child was delivered at 36 weeks of gestation because of intrauterine fetal distress. The diagnosis of osteopetrosis and partial agenesis of the corpus callosum was made shortly after delivery. The child died at 1 month without an autopsy. There are rare cases reported previously with the association of neuroaxonal dystrophy and osteopetrosis. We review these cases and compare them with ours.
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Affiliation(s)
- H Rees
- Department of Pathology, Vancouver General Hospital, University of British Columbia, Canada
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41
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Abstract
PURPOSE To determine the magnetic resonance (MR) imaging characteristics of amyotrophic lateral sclerosis (ALS) and to evaluate possible correlations between the disease severity and the MR imaging findings. MATERIALS AND METHODS The authors retrospectively reviewed MR images of the head in 17 patients with ALS (14 men and three women) and 17 age-matched control subjects. The corticospinal tract (CST) was analyzed for the following features: size, signal intensity, and number of sections and regions in which the CST could be seen. RESULTS Patients with ALS demonstrated sharp, well-defined, round, symmetric lesions that were hyperintense to gray matter within the CST. The lesions were best seen at the level of the middle or lower internal capsule on T2-weighted images. Visualization of the CST on proton-density-weighted images (which occurred in eight ALS patients) is the most reliable MR finding. Low signal intensity was identified within the motor cortex in six patients. Positive MR findings correlated with average or rapid progression of the disease. CONCLUSION Increased signal intensity in the CST on proton-density-weighted MR images is diagnostic for motor neuron disease and correlates with the rate of disease progression. Subtle ALS changes can be differentiated from the normal CST. Low signal intensity in the motor cortex on T2-weighted images is a useful finding.
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Affiliation(s)
- G Cheung
- Department of Neuroradiology, Sunnybrook Health Science Centre, North York, Ontario, Canada
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42
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Abstract
The PC10, a monoclonal antibody against proliferating cell nuclear antigen (PCNA), is known to show immunoreactivity in routinely processed paraffin embedded tissue. This antibody was applied to 72 astrocytic tumours from surgical biopsy material obtained in a ten year period. The PCNA labelling index (LI) obtained by image analysis was compared with patient's survival, age at diagnosis, and Karnofsky score as well as the histological grade of tumour. The survival analysis shows that patients with tumour PCNA LI of more than 6% have significantly poorer prognosis than those with 6% and below. In addition, there is also good correlation between PCNA LI with age, Karnofsky and tumour grade. This study suggests that although the PCNA expression of astrocytoma could be a useful predictor of patient's outcome, it is not an independent prognostic factor but has derived its statistical association with survival secondarily through its relationship with tumour grade, age and Karnofsky score.
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Affiliation(s)
- L C Ang
- Department of Pathology, Sunnybrook Health Science Centre, University of Toronto, Ontario, Canada
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43
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Abstract
A 64-year-old man presented with a three day history of progressive Broca's aphasia, followed within 3 weeks by exclusively right-sided myoclonus, rigidity, and dystonia. Within 4 weeks he was globally aphasic. He died within 7 weeks of onset. In the final week, rigidity and myoclonus became bilateral. CT and MRI were normal. SPECT showed diminished perfusion of the left hemisphere. EEG showed periodic discharges on the left. At autopsy, there were marked cortical spongiform change, neuronal loss, and gliosis throughout the left hemisphere and in the right occipital cortex. Elsewhere in the right hemisphere, spongiform change was non-existent to minimal. There was moderate spongiform change in the molecular layer of the cerebellar cortex, much more marked on the left. Clinical and pathological unilateral cerebral predominance extended to the ipsilateral cerebellum. Creutzfeldt-Jakob disease is an important consideration in patients with rapidly progressive unilateral cerebral signs associated with a movement disorder.
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Affiliation(s)
- A Kirk
- Division of Neurology, Royal University Hospital, University of Saskatchewan, Saskatoon, Canada
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44
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Rees H, Ang LC, Shul DD, George DH, Begley H, McConnell T. Increase in enkephalin-like immunoreactivity in hippocampi of adults with generalized epilepsy. Brain Res 1994; 652:113-9. [PMID: 7953707 DOI: 10.1016/0006-8993(94)90324-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The changes of opioid peptide reactivity in seizure activity have been well studied in animals. Increased enkephalin and dynorphin immunoreactivity in the hippocampi of animals are interpreted as the result of seizure induced mossy fibre sprouting. We studied the hippocampi of six patients with a history of long-standing grand mal seizures and six age-matched control patients with no history of epilepsy or neurologic disease, using frozen sections which were immunostained with antibodies against Leu-enkephalin and Met-enkephalin. The staining intensity in the CA3, CA4 and internal molecular layer of the dentate fascia in each case was quantified using optical densitometry image analysis. The CA3 and CA4 of the epileptic hippocampi showed highly significant increase in Leu-enkephalin-like immunoreactivity compared to the controls (P < 0.005) while the inner molecular layer showed only significant increase (P < 0.05). Met-Enkephalin-like immunoreactivity was only significantly increased in CA4 of the epileptic hippocampi (P < 0.05).
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Affiliation(s)
- H Rees
- Department of Pathology, Royal University Hospital, University of Saskatchewan, Canada
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45
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Chen L, Richardson JS, Caldwell JE, Ang LC. Regional brain activity of free radical defense enzymes in autopsy samples from patients with Alzheimer's disease and from nondemented controls. Int J Neurosci 1994; 75:83-90. [PMID: 8050854 DOI: 10.3109/00207459408986291] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Several lines of evidence support the hypothesis that oxygen free radicals are involved in the destruction of neurons in various degenerative disorders of the central nervous system. The activities of superoxide dismutase, catalase and glutathione peroxidase, three enzymes that contribute to the cellular defenses against free radical damage, were measured in different areas of autopsy brains from patients with Alzheimer's disease and from age matched controls. All brains were removed within 24 hours of the time of death and were cut in half sagitally. One half was stored frozen at -86 degrees C and the other half was examined histologically to confirm the presence or absence of Alzheimer's disease. Samples were taken from the frozen half for the enzyme assays. In control brains, the activity of superoxide dismutase is significantly higher in the cerebellum, frontal cortex and hippocampus than it is in the temporal cortex, parietal cortex and entorhinal cortex. The activity of catalase is significantly higher in cerebellum and frontal cortex than in hippocampus, parietal cortex and entorhinal cortex. Glutathione peroxidase activity is uniform across all brain areas studied. In Alzheimer's brains, superoxide dismutase activity is not statistically different among the various brain regions studied, but it is significantly lower than control in the cerebellum (-27%), frontal cortex (-27%) and hippocampus (-35%). Catalase is significantly higher in Alzheimer's cerebellum, frontal cortex and temporal cortex than in Alzheimer's hippocampus, parietal cortex and entorhinal cortex. However, there are no significant differences in catalase activity between Alzheimer's and control samples.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- L Chen
- Department of Pharmacology, College of Medicine, University of Saskatchewan, Saskatoon, Canada
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46
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Abstract
Neuronal intranuclear hyaline inclusion disease is a progressive, fatal neurologic condition characterized by eosinophilic inclusions in neurons of the central, autonomic, and peripheral nervous systems. The clinical and pathologic findings of a 4-year-old boy who presented with a rapidly progressive cerebellar ataxia and seizure disorder that had begun 2 years earlier are described. Although intraneuronal inclusions were identified in neurons of cortex, basal ganglia, brainstem, cerebellum, and spinal cord, clinical signs were restricted to cerebellar ataxia, internuclear ophthalmoplegia, and cognitive delay. Predominant cerebellar atrophy, early age of onset, and short clinical course distinguishes it from previously reported patients.
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Affiliation(s)
- A E Sloane
- Division of Neurology, Hospital for Sick Children, Toronto, Ontario, Canada
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47
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Al-Tweigeri T, Shuaib A, Denath F, Ang LC, Khan M, Bourgault RM. Glioblastoma multiforme presenting with recurrent neurological deficits: Transient ischemic attacks or tumor attacks. J Stroke Cerebrovasc Dis 1994; 4:42-5. [PMID: 26487534 DOI: 10.1016/s1052-3057(10)80145-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Transient ischemic attacks result from the temporary focal interruption of blood flow to the brain. We present three patients with glioblastoma multiforme and recurrent speech arrests or right-sided numbness. The clinical diagnosis of "transient ischemic attack" was made in each patient. This diagnosis remained unchanged for months to 2 years after initial presentation and investigations. The correct diagnosis was made with a brain biopsy in two patients and as a result of additional investigations in the third patient. It is important to remember brain tumor in the differential diagnosis of patients presenting with recurrent brief neurological symptoms.
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Affiliation(s)
- T Al-Tweigeri
- From the Department of Medicine (Neurology), Saskatoon, Saskatchewan, Canada
| | - A Shuaib
- From the Department of Medicine (Neurology), Saskatoon, Saskatchewan, Canada.; The Saskatchewan Stroke Research Centre, Saskatoon, Saskatchewan, Canada
| | - F Denath
- The Department of Radiology (Neuroradiology), Saskatoon, Saskatchewan, Canada
| | - L C Ang
- The Department of Pathology (Neuropathology), Saskatoon, Saskatchewan, Canada
| | - M Khan
- The Department of Neurosurgery, Saskatoon, Saskatchewan, Canada.; The Saskatchewan Stroke Research Centre, Saskatoon, Saskatchewan, Canada
| | - R M Bourgault
- From the Department of Medicine (Neurology), Saskatoon, Saskatchewan, Canada
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48
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Abstract
A number of laboratories have shown that astrocytes protect neurons from glutamate excitotoxicity. The experiments described in this paper were designed to address the question whether prior exposure of astrocytes to aluminum (in the form of aluminum citrate) interfered with the ability of astrocytes to protect neurons from glutamate excitotoxicity. Our culture paradigm consisted of highly enriched cultures of neurons and astrocytes grown on separate coverslips; this design enables one to subject either the neurons or the astrocytes to specific treatments and recombine the cells into the same petri dish simply by moving coverslips from dish to dish. We have confirmed findings of other laboratories that astrocytes could protect neurons from glutamate-induced death when glutamate (100 microM) is added to the culture medium. We have also demonstrated that prior treatment of astrocytes with 100 microM aluminum citrate impairs this ability of astrocytes to promote neuronal survival. No differences, however, were observed in the ability of control and aluminum-treated astrocytes to take up glutamate. These findings suggest that aluminum may cause astrocytes to: (i) secrete a factor that makes neurons more susceptible to glutamate-induced toxicity; (ii) secrete a neuronotoxic factor in the presence of glutamate; or (iii) reduce secretion of a factor that protects neurons from glutamate excitotoxicity.
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Affiliation(s)
- J B Sass
- Department of Anatomy, University of Saskatchewan, Saskatoon, Canada
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49
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Ang LC, Bhaumick B, Juurlink BH. Neurite promoting activity of insulin, insulin-like growth factor I and nerve growth factor on spinal motoneurons is astrocyte dependent. Brain Res Dev Brain Res 1993; 74:83-8. [PMID: 8403378 DOI: 10.1016/0165-3806(93)90086-p] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Mouse motoneurons were isolated from dissociated E15 mouse spinal cord and grown on polyornithine-coated round coverslips in a growth medium (DMEM/F12) supplemented with progesterone, trans-ferrin, selenium, horse serum and muscle extract. Astrocytes from newborn mouse neopallium were grown on rectangular coverslips. The motoneuron neurite growth was determined at day 8 of culture by counting, using the light microscope, the intersections produced by neurites radiating from the perikaryon placed centrally in a graticule eyepiece of concentric circles. The mean intersections for cultures without addition of astrocytes, insulin, insulin-like growth factor I (IGF-I) or nerve growth factor (NGF) was 12.6 +/- 0.8. When astrocytes on a separate coverslip were introduced from day 1, there was a small increase in neurite growth (16.3 +/- 0.9). The neurite growth was further increased significantly with the addition of insulin (27.3 +/- 1.4), IGF-I (31.5 +/- 1.4) or NGF (21.8 +/- 1.1) to cultures with astrocytes. Insulin, IGF-I or NGF in the absence of astrocytes did not greatly increase the neurite growth. We conclude that insulin, IGF-I and NGF promote neurite growth through some interactions with astrocytes.
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Affiliation(s)
- L C Ang
- Department of Pathology (Neuropathology), University of Saskatchewan, Saskatoon, Canada
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50
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Abstract
Drowning is a well-recognized cause of death in persons with epilepsy. Investigation of bathtub drowning is often not straightforward. We report three cases of bathtub water drowning of patients with neuropathological bases for seizures. The importance of neuropathological examination is discussed. A high index of suspicion is required for all cases of bathtub-related death, even in the absence of history of previous seizure disorders. Neuropathological examination must be performed to look for anatomical lesions associated with seizures. Identification of these findings could be very helpful in ruling out homicide or suicide as the cause of death in bathtub drownings.
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Affiliation(s)
- A Saxena
- Department of Pathology, Royal University Hospital, Saskatoon, Saskatchewan, Canada
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