Effects of Macrophage Transplantation in the Injured Adult Rat Spinal Cord: A Combined Immunocytochemical and Biochemical Study
Franzen, Rachelle ; Schoenen, Jean ; Leprince, Pierre et al
in Journal of Neuroscience Research (1998), 51(3), 316-27
Early and robust invasion by macrophages may be one of the reasons why axonal regeneration is more effective in the PNS than in the CNS. Therefore, we have grafted autologous peritoneal macrophages ... [more ▼]
Early and robust invasion by macrophages may be one of the reasons why axonal regeneration is more effective in the PNS than in the CNS. Therefore, we have grafted autologous peritoneal macrophages labeled with fluorescent latex microspheres into spinal cord compression lesions. At various survival times, we have studied their effect on the expression of neuronal (neurofilaments [NF], calcitonin gene-related peptide [CGRP], 5-hydroxytryptamine [5-HT]) and nonneuronal markers (myelin-associated glycoprotein [MAG], glial fibrillary acidic protein [GFAP], laminin) by using semiquantitative Western blot and immunohistochemical techniques. After 1 month, we observed a significant decrease of the expression of MAG as well as an important invasion of the lesion site by neurites, chiefly peptidergic axons of presumed dorsal root origin, in macrophage-grafted animals compared with controls. In addition, angiogenesis and Schwann cell infiltration were more pronounced after macrophage grafts, providing an increase in laminin, a favorable substrate for axonal regrowth. By using reverse transcription-polymerase chain reaction (RT-PCR), mRNAs for tumor necrosis factor-alpha (TNF-alpha) were detected in the transplanted cells, whereas results were negative for nerve growth factor (NGF), neurotrophin-3 (NT-3), brain-derived neurotrophic factor (BDNF), or acidic fibroblast growth factor (aFGF) and basic fibroblast growth factor (bFGF). Thus, macrophage grafts may represent an interesting strategy to promote axonal regeneration in the CNS. Our study suggests that they may exert their beneficial effects by degrading myelin products, which inhibit axonal regrowth, and by promoting a permissive extracellular matrix containing notably laminin. No evidence for a direct synthesis of neurotrophic factors by the transplanted macrophages was found in this study, but resident glial cells could secrete such factors as a result of stimulation by macrophage-released cytokines. [less ▲]Detailed reference viewed: 19 (1 ULg)
Comparative Evaluation of Cerebral Aneurysms with Selective Arterially Enhanced Ct and Dsa
; ; et al
in European Radiology (1998), 8(7), 1181-6
The purpose of our study was to compare selective arterially enhanced spiral computed tomographs (ACT) with digital subtraction angiographies (DSA) in the presurgical assessment of cerebral aneurysms. A ... [more ▼]
The purpose of our study was to compare selective arterially enhanced spiral computed tomographs (ACT) with digital subtraction angiographies (DSA) in the presurgical assessment of cerebral aneurysms. A total of 24 aneurysms in 18 patients were explored in a prospective study by ACT and DSA, using an interactive combined CT-angiography suite. Dimensions of the aneurysm, its relation to the parent vessel, and the aneurysmal index were defined on DSA and on surface-shaded display of 3D reformatted images obtained from ACT. Results were correlated with surgical findings. Three aneurysms suspected on DSA were not confirmed by ACT. One fusiform aneurysm suspected on DSA corresponded to a sacciform aneurysm on ACT. Surgical findings confirmed 20 sacciform aneurysms. The aneurysmal index could be measured in all 20 cases of sacciform aneurysms on ACT and could not be determined with confidence in 55 % of the cases on DSA. DSA and ACT gave identical results in 35 % of cases. In 10 %, the index measured by ACT was superior to that determined by DSA for aneurysms which had a diameter of less than 3 mm. In conclusion, the combination of DSA and ACT improved the results of DSA alone. ACT is a reliable method to measure the aneurysmal index in aneurysms with a diameter superior to 3 mm. [less ▲]Detailed reference viewed: 18 (1 ULg)
Spontaneous longitudinally orientated axonal regeneration is associated with the Schwann cell framework within the lesion site following spinal cord compression injury of the rat.
; ; Franzen, Rachelle et al
in Journal of Neuroscience Research (1998), 53(1), 51-65
Spontaneous cellular reorganisation at the lesion site has been investigated following massive spinal cord compression injury in adult rats. By 2 days post operation (p.o.), haemorrhagic necrosis ... [more ▼]
Spontaneous cellular reorganisation at the lesion site has been investigated following massive spinal cord compression injury in adult rats. By 2 days post operation (p.o.), haemorrhagic necrosis, widespread axonal degeneration, and infiltration by polymorphnuclear granulocytes and OX42-positive macrophages were observed in the lesion site. By 7 days p.o., low affinity nerve growth factor receptor-positive Schwann cells, from activated spinal roots, were identified as they migrated far into the lesion. Between 7 and 14 days p.o., the overlapping processes of Schwann cells within the macrophage-filled lesion formed a glial framework which was associated with extensive longitudinally orientated ingrowth by many neurofilament-positive axons. Relatively few of these axons were calcitonin gene-related peptide (CGRP)-, substance P (SP)-, or serotonin (5HT)-positive; however, many were glycinergic or gamma aminobutyric acid (GABA)ergic. At 21 and 28 days p.o. (the longest survival times studied), a reduced but still substantial amount of orientated Schwann cells and axons could be detected at distances of up to 5 mm within the lesion. Glial fibrillary acidic protein (GFAP) immunoreactivity demonstrated the slow formation of astrocytic scarring which only became apparent at the lesion interface between 21 and 28 days p.o. The current data suggest the possibility of developing future therapeutic strategies designed to maintain or even enhance these spontaneous and orientated regenerative events. [less ▲]Detailed reference viewed: 23 (0 ULg)
Spontaneous axonal regeneration into the lesioned site following closed contusion injury to the adult rat spinal cord.
; ; et al
Conference (1997, October)Detailed reference viewed: 6 (0 ULg)
Le pied tombant (foot drop). Un problème de diagnostic différentiel
Dubuisson, Annie ; Martin, Didier ; Lenelle, Jacques et al
in Revue Médicale de Liège (1997), 52(5), 355-62Detailed reference viewed: 228 (8 ULg)
Sequential successful surgical management of extracranial internal carotid stenosis and ipsilateral intracranial aneurysm. Case reports.
Detry, Olivier ; Defraigne, Jean-Olivier ; Desiron, Quentin et al
in Vascular Surgery (1997), 31
The coexistence of extracranial internal carotid stenosis and ipsilateral intracranial aneurysm is a rare event whose management is controversial. Theoretically, the correction of a significant stenosis ... [more ▼]
The coexistence of extracranial internal carotid stenosis and ipsilateral intracranial aneurysm is a rare event whose management is controversial. Theoretically, the correction of a significant stenosis of the extracranial internal carotid may lead to an increase in the downstream pressure in the intracranial carotid, and may consequently increase the risk of rupture of the ipsilateral aneurysm. Moreover, dramatic increase of blood pressure is not uncommon after carotid endarterectomy, and may promote aneurysmal rupture. Intracranial surgical correction of a hypoperfused aneurysm down to extracranial carotid stenosis should carry an increased risk of inadequate cerebral flow during procedure, and unspecific postoperative stimulation of platelets aggregation and coagulation may complete obstruction of a subtotal carotid stenosis. We report the cases of two patients successfully treated by a two-stage surgical procedure. In a first step, the intracerebral aneurysms were controlled and electively excluded by clipping. In a second step, carotid endarteriectomies were performed some days later without any neurological complications. Postoperative recoveries were uneventful and six months after these surgical procedures, clinical examination of both patients did not reveal any worsening of the preoperative neurological status. [less ▲]Detailed reference viewed: 32 (5 ULg)
Grafting cultured macrophages or fibroblasts in a contusion model of adult rat spinal cord : a combined morphological and biochemical study of neuronal and non-neuronal actors in repair processes.
Franzen, Rachelle ; Martin, Didier ; et al
Conference (1997)Detailed reference viewed: 14 (3 ULg)
Current concepts in the prevention, diagnosis and treatment of the cervical whiplash syndrome : Acute cervical central cord syndrome.
Conference (1996, November 15)Detailed reference viewed: 6 (1 ULg)
Nt-3 Has a Tropic Effect on Process Outgrowth by Postnatal Auditory Neurones in Vitro
Malgrange, Brigitte ; LEFEBVRE, Philippe ; Martin, Didier et al
in Neuroreport (1996), 7(15-17), 2495-9
CONFOCAL analysis of early postnatal auditory neurones in a bicompartmental culture system was used to test for chemoattractant properties of NGF, BDNF and NT-3 on neuronal process outgrowth. NT-3 exerted ... [more ▼]
CONFOCAL analysis of early postnatal auditory neurones in a bicompartmental culture system was used to test for chemoattractant properties of NGF, BDNF and NT-3 on neuronal process outgrowth. NT-3 exerted a strong tropic effect on neuritic outgrowth from auditory neurones in this system. BDNF and NGF did not have any tropic activity that directed processes outgrowth from auditory neurones. However, BDNF was important for the support of neuronal survival in NGF-treated cultures and for neuritogenesis in NT-3-treated cultures. Since NT-3 has been identified as both a survival factor and a chemotropic agent for auditory neurones, it is likely that this neurotrophin will be a useful therapeutic agent in the treatment of damaged cochleae for the recovery of hearing. [less ▲]Detailed reference viewed: 29 (1 ULg)
Intraarterial spiral CT angiography combined with DSA in pretherapeutic assessment of cerebral aneurysms.
; ; Dondelinger, Robert et al
Conference (1996, September 21)Detailed reference viewed: 12 (0 ULg)
Effects of Schwann Cell Transplantation in a Contusion Model of Rat Spinal Cord Injury
Martin, Didier ; Robe, Pierre ; Franzen, Rachelle et al
in Journal of Neuroscience Research (1996), 45(5), 588-597
Cultured Schwann cells were transplanted at various delays into a spinal cord contusion injury performed at low thoracic level in adult female rats. The Schwann cells were purified from the dorsal root ... [more ▼]
Cultured Schwann cells were transplanted at various delays into a spinal cord contusion injury performed at low thoracic level in adult female rats. The Schwann cells were purified from the dorsal root ganglia of adult syngeneic animals. the transplants were well tolerated, and the transplanted Schwann cells invaded the injured spinal cord. As quantified using video image analysis, the survival and growth of the transplanted cells were poor when the grafting procedure was performed 3-4 days after injury and very good when performed immediately or 10 days after injury, in which cases post-traumatic micro- and macrocavitation were strongly reduced. In animals grafted immediately after injury but not in animals grafted after 10 days, post-traumatic astrogliosis was much reduced. The Schwann cells transplanted area was invaded by numerous regenerating axons, the vast majority of which were, based on the neurotransmitter (CGRP and SP) profile, originating from dorsal root ganglion. No regeneration of the corticospinal tract as assessed after anterograde tracing or of descending aminergic fibers could be demonstrated. [less ▲]Detailed reference viewed: 42 (5 ULg)
Exérèse sous contrôle vidéoscopique de neurinomes intrathoracique: réflexions à propos de trois cas.
Lenelle, Jacques ; Martin, Didier ; et al
Conference (1996, June 16)Detailed reference viewed: 19 (1 ULg)
Pretherapeutic assessment of intracranial aneurysms with intra-arterially enhanced 3-D CT-angiography.
Martin, Didier ; Lenelle, Jacques ; et al
Conference (1996, April 27)Detailed reference viewed: 6 (0 ULg)