Devic disease with brainstem lesions.

We describe a patient who suffered from an unusually severe form of neuromyelitis optica with a hyperacute time-course evolution requiring mechanical ventilation within 3 days. The patient died after 72 days and autopsy showed major spinal cord, optic nerve, and brainstem necrosis, and multifocal necrotic lesions on the cerebellum and cerebral white matter.

Chromosome 1p loss: a favorable prognostic factor in low-grade gliomas.

Search for loss of heterozygosity on chromosomes 1p, 9p, 10q, and 19q, epidermal growth factor receptor (EGFR) gene amplification, and p53 expression was performed in a series of 131 low-grade gliomas. The profile of molecular changes, clinical findings, and histology were subsequently correlated with the course of the disease, mainly progression-free survival. When these parameters were considered as candidate variables in a multivariate analysis, only loss of heterozygosity on chromosome 1p was associated with increased progression-free survival (hazard ratio, 0.

In vivo fusion of circulating fluorescent cells with dystrophin-deficient myofibers results in extensive sarcoplasmic fluorescence expression but limited dystrophin sarcolemmal expression.

To investigate the therapeutic potential of bone marrow transplantation in Duchenne muscular dystrophy, green fluorescent protein-positive (GFP+) bone marrow cells were transplanted into irradiated wild-type and dystrophin-deficient mdx mice. Tibialis anterior muscles showed fivefold to sixfold more GFP+ mononucleated cells and threefold to fourfold more GFP+ myofibers in mdx than in wild-type mice. In contrast, dystrophin expression in mdx mice remained within the level of nontransplanted mdx mice, and co-expression with GFP was rare.

Capsule structure changes associated with Cryptococcus neoformans crossing of the blood-brain barrier.

Cryptococcus neoformans is a yeast responsible for disseminated meningoencephalitis in patients with cellular immune defects. The major virulence factor is the polysaccharide capsule. We took advantage of a relevant murine model of disseminated meningoencephalitis to study the early events associated with blood-brain barrier (BBB) crossing.

Expression of excitatory amino acid transporter-1 (EAAT-1) in brain macrophages and microglia of patients with prion diseases.

The mechanisms of neuronal apoptosis in prion diseases are unclear. Experimental studies suggest that it may result from 2 associated mechanisms: glutamate-mediated excitotoxicity and oxidative stress. Recent studies showed that activated macrophages/microglia (AMM) express excitatory amino acid transporters (EAATs) in HIV infection, suggesting that they may play a neuroprotective role by clearing extra-cellular glutamate and producing anti-oxidant glutathione.

Elucidation of the mechanism of inhibition of cyclooxygenases by acyl-coenzyme A and acylglucuronic conjugates of ketoprofen.

Nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit the cyclooxygenase (COX) isoforms which accounts for their clinical effects. The differential inhibition of COX-1 and COX-2 is not sufficient to explain the absence of a correlation between in vitro and in vivo effects, especially for 2-aryl-propionates, thus indicating the participation of metabolites. Conjugates to glucuronic acid and to coenzyme-A are mainly produced, and have been shown to be chemically reactive.

A short route to enantiomerically pure benzophenanthridinone skeleton: synthesis of lactone analogues of narciclasine and lycoricidine.

Condensation of functionalized o-toluamide anions on a carbohydrate-derived lactone, followed by intramolecular aldol cyclization, provides enantiomerically pure 2-arylcyclohexenones. Different approaches for the stereoselective transformation of the carbonyl group of these key intermediates into an amino group were unsuccessful. However 1,4-addition of thiolate and concomitant ring closure to isocoumarine provided a useful method for the transformation of the tertiary amide function.

Correlation of in vitro infiltration with glioma histological type in organotypic brain slices.

Diffuse invasion of the brain, an intrinsic property of gliomas, renders these tumours incurable, and is a principal determinant of their spatial and temporal growth. Knowledge of the invasive potential of gliomas is highly desired in order to understand their behaviour in vivo. Comprehensive ex vivo invasion studies including tumours of different histological types and grades are however lacking, mostly because reliable physiological invasion assays have been difficult to establish.

[Neurotoxicity and neuroprotection, two aspects of microglial activation in human immunodeficiency virus (HIV) infection].

Microglial cells and macrophages are the only cells within the central nervous system, in which productive HIV infection has been unquestionably demonstrated. Those cells play a key role in the origin of the neuronal dysfunction underlying HIV-related cognitive disorders. The neurotoxicity of the cells is both direct, related to HIV proteins, and indirect, through the release by activated macrophages and microglial cells (AMM) of multiple neurotoxic factors.

Giant supratentorial enterogenous cyst: report of a case, literature review, and discussion of pathogenesis.

Objective And Importance: To describe a histologically well-documented adult case of a giant supratentorial enterogenous cyst (EC). Fewer than 15 cases of supratentorial ECs are on record: 8 associated with the brain hemispheres or the overlying meninges, 4 with the sellar region, and 2 with the optic nerve.

Clinical Presentation: A 31-year-old woman complained of long-standing mild left brachial and crural motor deficit precipitated by headache and signs of intracranial hypertension.

Adult bone marrow-derived stem cells in muscle connective tissue and satellite cell niches.

Skeletal muscle includes satellite cells, which reside beneath the muscle fiber basal lamina and mainly represent committed myogenic precursor cells, and multipotent stem cells of unknown origin that are present in muscle connective tissue, express the stem cell markers Sca-1 and CD34, and can differentiate into different cell types. We tracked bone marrow (BM)-derived stem cells in both muscle connective tissue and satellite cell niches of irradiated mice transplanted with green fluorescent protein (GFP)-expressing BM cells. An increasing number of GFP+ mononucleated cells, located both inside and outside of the muscle fiber basal lamina, were observed 1, 3, and 6 months after transplantation.

Up-regulation of glutamate concentration in the putamen and in the prefrontal cortex of asymptomatic SIVmac251-infected macaques without major brain involvement.

We quantified putamen and prefrontal cortex metabolites in macaques with simian immunodeficiency virus infection and searched for virological and histological correlates. Fourteen asymptomatic macaques infected since 8-78 months (median: 38) were compared with eight uninfected ones. Absolute concentrations of acetate, alanine, aspartate, choline, creatine, GABA, glutamate, glutamine, lactate, myo-inositol, N-acetylaspartate, taurine and valine were determined by ex vivo proton magnetic resonance spectroscopy.

[The neuropathology of HIV infection in the era of highly active antiretroviral therapy].

Introduction of Highly Active Antiretroviral Treatment (HAART) which is available for most AIDS patients in France since 1996, has resulted in a dramatic improvement of the disease course. From the survey of our autopsy series of (AIDS) cases and the review of other neuropathological studies from different developed countries, we found quantitative and qualitative changes in the pattern of human immunodeficiency virus (HIV) neuropathology. Quantitatively, there was a dramatic decrease in the number of autopsy cases but brain involvement remained a major cause of death in AIDS patients.

Expression of excitatory amino acid transporter-1 in brain macrophages and microglia of HIV-infected patients. A neuroprotective role for activated microglia?

Recent experimental studies showed that activated macrophages/microglia (AMM) express excitatory amino acid transporters (EAATs), suggesting that, in addition to their neurotoxic properties, they also have a neuroprotective role by clearing extracellular glutamate and producing antioxidant glutathione. To test this hypothesis in human, the brain of 12 HIV-positive patients and 3 controls were immunostained for EAAT-1. EAAT-1 was expressed by AMM in all HIV-infected cases but not in HIV-negative controls.

The changing pattern of HIV neuropathology in the HAART era.

Highly active antiretroviral treatment (HAART), which has been available for most AIDS patients in France since 1996, has resulted in a dramatic improvement of the progression of the disease. From the survey of our series of 343 brains with acquired immunodeficiency syndrome (AIDS) from patients who died between 1985 and 2002, we found both quantitative and qualitative changes in the pattern of human immunodeficiency virus (HIV) neuropathology. Quantitatively, despite a dramatic decrease in the number of autopsies, brain involvement remained a major cause of death.

Involvement of the glycoproteic meshwork of cervical mucus in the mechanism of sperm orientation.

Background: The aim of this study was to investigate the influence of the solid phase of the mucus hydrogel in facilitating the upward movement of spermatozoa during the menstrual cycle.

Methods: A total of 171 sperm migration experiments using 47 selected ovulatory mucus samples were performed in vitro in tubes of various shape and diameter. Physical constraints applied to cervical mucus combined with scanning electron microscopy (SEM) techniques permitted analysis of the mechanism of sperm orientation within cervical mucus submitted to capillary constraints simulating the various conditions of sperm orientation in vivo.

Regulated expression of sodium-dependent glutamate transporters and synthetase: a neuroprotective role for activated microglia and macrophages in HIV infection?

It is now widely accepted that neuronal damage in HIV infection results mainly from microglial activation and involves apoptosis, oxidative stress and glutamate-mediated neurotoxicity. Glutamate toxicity acts via 2 distinct pathways: an excitotoxic one in which glutamate receptors are hyperactivated, and an oxidative one in which cystine uptake is inhibited, resulting in glutathione depletion and oxidative stress. A number of studies show that astrocytes normally take up glutamate, keeping extracellular glutamate concentration low in the brain and preventing excitotoxicity.

[Degradation of copper IUDs in utero. The process of metallic corrosion. A scanning electron microscope study].

Objective: The present investigation was carried out in order to study the process of metallic corrosion of copper IUD's in utero, to precise its dynamics and location along the IUD and to appraise the influence of eventual calcareous deposition.

Material And Methods: A total of 461 copper IUDs representing four standard models were screened by means of optical microscopy. Especially typical samples were studied at higher magnifications under the scanning electron microscope.

[Physiopathology of meningoencephalitis caused by Cryptococcus neoformans].

Cryptococcus neoformans is an encapsulated yeast mainly responsible for meningoencephalitis, especially in AIDS patients. Recent observations using an experimental model of systemic cryptococcosis that mimics the human infection have reinforced the knowledge on the pathogenesis of cryptococcosis. Cryptococcosis may occur several years after inhalation of infecting particles from the environment.

Expression of excitatory amino acid transporter-2 (EAAT-2) and glutamine synthetase (GS) in brain macrophages and microglia of SIVmac251-infected macaques.

Na+-dependent transporters for glutamate (excitatory amino acid transporters, EAATs) clear extracellular glutamate in the brain and prevent excitotoxic neuronal damage. Glutamine synthetase (GS) provides metabolic support for neurones by producing the neurotrophic amino acid glutamine. EAAT and GS expression has recently been demonstrated in macrophages and microglial cells in vitro, and in two models of acute inflammation in vivo.

Pathogenesis of cerebral Cryptococcus neoformans infection after fungemia.

The pathogenesis of cerebral infection after Cryptococcus neoformans fungemia in outbred mice was investigated. Confocal microscopy and cultures on ficoll-hypaque gradient-separated blood cells were used to detect yeasts in the cytoplasms of monocytes. In semithin brain sections, poorly capsulated yeasts were seen in macrophages in the leptomeningeal space, in monocytes circulating in leptomeningeal capillaries, or in the endothelial cells themselves, strengthening the hypothesis that monocytes and endothelial cells play key roles in the pathogenesis of cryptococcal meningitis.