Changes in anion permeability following hypotonic challenge in rat brain endothelial cells: different responses in primary cultures and in immortalised RBE4 cells.

Hypotonicity-induced anion permeability changes were investigated but not detected in immortalised (RBE4) rat brain endothelial cells using iodide efflux measurements. Large, rapid increases were however observed in primary cultured cells. Both cell types were reinvestigated following culture in a common growth factor-depleted medium.

Modulation of P-glycoprotein activity by glial factors and retinoic acid in an immortalized rat brain microvessel endothelial cell line.

P-glycoprotein (P-gp), a product of the multidrug-resistant (mdr) genes, is expressed in the endothelial cells of the blood-brain barrier (BBB). Effects of glial factors and retinoic acid (RA) on P-gp activity and level were investigated in the immortalized rat brain endothelial cell line RBE4, which expressed immunodetectable P-gp associated with a decrease in accumulation of the P-gp substrates, vinblastine and colchicine. When RBE4 cells were cultured either in the presence of C6-conditioned medium or on C6- or astrocyte-extracellular matrix, intracellular vinblastine and colchicine concentrations were decreased.

F-actin cytoskeleton and sucrose permeability of immortalised rat brain microvascular endothelial cell monolayers: effects of cyclic AMP and astrocytic factors.

The immortalised RBE4 cell line, derived from rat brain capillary endothelial cells, preserves many features of the in vivo brain endothelium, and hence is of interest as a potential in vitro model of the blood-brain barrier (BBB). This study reports the effects of elevated intracellular cAMP and factors released by astrocytes on the F-actin cytoskeleton and paracellular sucrose permeability of monolayers of RBE4 cells. RBE4 cells grown in control medium showed a marked increase in the F-actin staining at the cytoplasmic margin at confluence, which was not significantly enhanced by elevation of intracellular cAMP and/or addition of astrocyte-conditioned medium (ACM).

[Stereotaxic technics and clinical neurosurgery].

Stereotactic methodology developed at Sainte-Anne Hospital Center from 1947 is based on the application of a simple spatial geometry-the Talairach Ac-Pc reference system-to the cranial volume and the identification of any anatomical structure or brain lesion within this volume. Now upgraded with modern imaging techniques, this methodology is the ground for multiple applications in functional as well as lesional neurosurgery and is now a a part of the daily neurosurgical practice at Sainte-Anne Hospital. Stereotactic procedures include three steps: first, the identification of one or several target-volumes through stereotactic imaging acquisition: CT, MRI and conventional stereoscopic angiography; second, the image treatment on a dedicated workstation for stereotactic coordinates determination and surgical planning; third, the surgical procedure itself and its control.

Extradural spinal tophaceous gout: evolution with medical treatment.

A patient with chronic tophaceous gouty arthritis developed paraparesis due to medullar compression from a urate sodium tophus. We report the MRI features of this tophaceous gout, which showed an extradural hyperintense signal with an isointense nodule signal on T1 weighted sequences. Surgical removal of the epidural lesion resulted in complete clinical recovery.

Role of P-glycoprotein in colchicine and vinblastine cellular kinetics in an immortalized rat brain microvessel endothelial cell line.

Uptake and efflux of colchicine and vinblastine, whose effects are related to their high-affinity binding to tubulin, were studied in the immortalized rat brain microvessel endothelial cell line RBE4. At 10 nM extracellular drug concentration, uptake equilibrium was approached at 45 hr for colchicine, but at only 3.5 hr for vinblastine.

Glucose transport in immortalized rat brain capillary endothelial cells in vitro: transport activity and GLUT1 expression.

RBE4 cells, an immortalized cell line derived from primary cultures of rat brain capillary endothelial cells, transport 3-O-methylglucose by a mechanism which is saturable with an apparent Km of 14.3 mM. The 3-O-MG uptake can be inhibited by other potential substrates and by non-competitive inhibitors, but not by L-glucose or sucrose.

Usefulness of longitudinal evaluation of Cyfra 21-1 variations in advanced lung cancer monitoring.

To investigate the usefulness of Cyfra 21-1 as an indicator of therapy effectiveness and prognosis in advanced primary lung cancer, sixty-three patients were selected on the basis of a high Cyfra 21-1 serum level (> 3.3 ng/ml) at the time of diagnosis. Serial assays of Cyfra 21-1 were performed during the first three courses of chemotherapy among 63 patients.

Parenchymal changes after radiosurgery of cerebral arteriovenous malformations. Preliminary report of a proposed classification.

Radiosurgery of cerebral arteriovenous malformations (cAVM) can induce parenchymal changes seen on MRI. The purpose of this study was to classify these changes and to correlate them to clinical outcome and obliteration of the cAVM. 142 patients with cAVM underwent radiosurgery with a linear accelerator between 1994 and 1995.

Motor functional MRI for presurgical evaluation of cerebral tumors.

Objective: To evaluate the capabilities and the limitations of motor functional magnetic resonance imaging (fMRI) in the presurgical evaluation of the cerebral tumors located in or near the motor homunculus. To correlate each type of activation with the histologic characteristics of each tumor.

Materials And Methods: fMRI was performed in 17 patients (14 adults and 3 children), without any motor deficit, presenting with various intracerebral tumors.

Potential interest of anti-ischemic agents for limiting cyclosporin A nephrotoxicity.

Chronic administration of cyclosporin A induces nephrotoxicity in humans. This is related to a cyclosporin A-induced constriction of afferent glomerular arterioles and mesangial cells, which leads to a decrease in filtration pressure and creatinine clearance. Afterwards, cellular lesions are observed involving mainly tubular atrophy and interstitial fibrosis, both of which are nonspecific.

[Malignant ethmoid-sphenoidal tumors. 130 cases. Retrospective study].

We report on 130 ethmoidal cancers. 96 (74%) were adenocarcinomas (ADKE). 110 were operated upon between 1984 and 1996: 9.

[Malignant tumors of the ethmoid region. Neurosurgical techniques].

We describe the main neurosurgical approaches in use for removing cancers of the ethmoid region: a) the classical subfrontal procedure usually combined with a transfacial approach, b) the sub-fronto-orbito-nasal approach (SFON) now performed in a majority of procedures as long as the tumor does not present with a large intra-cranial and/or maxillary extension. The advantages and drawbacks of both techniques are discussed. The progressive simplification of techniques for anterior cranial base reconstruction is explained and warranted.

[Trans-facial approaches of cancers of the ethmoid].

Lateral rhinotomy, midface degloving approach and medial maxillectomy are described. Lateral rhinotomy allows for a wide surgical approach, complete tumor removal with safe margins and satisfying cosmetic result. Lateral rhinotomy with medial maxillectomy is recommended for surgical resection of ethmoid sinus carcinoma.

Angioarchitecture associated with haemorrhage in cerebral arteriovenous malformations: a prognostic statistical model.

The overall haemorrhagic risk of a cerebral arteriovenous malformation (cAVM) is 2-4% per year. However, the individual risk of haemorrhage has never been determined. This study was undertaken to assess the haemorrhage risk of an individual cAVM.

Interstitial laser thermotherapy: developments in the treatment of small deep-seated brain tumors.

New technical advances have made feasible the utilization of laser to destroy deep-seated brain tumors under real-time monitoring. Experience with interstitial laser thermotherapy (ILTT) in animal and clinical studies has been obtained. These studies are summarized and the future potential of ILTT in neurosurgery is discussed.

Intraspinal meningiomas: review of 54 cases with discussion of poor prognosis factors and modern therapeutic management.

Introduction: Intraspinal meningiomas account for 25%-46% of primary spinal cord tumors. Technical advances in magnetic resonance imaging (MRI) and surgical procedures (ultrasonic cavitation aspirators [CUSA], lasers) have brought about better clinical results. In spite of these new techniques, a small percentage of patients still present with poor postoperative results and/or a recurrence.

Ethanol potentiates lipopolysaccharide- or interleukin-1 beta-induced nitric oxide generation in RBE4 cells.

Our present study investigated the effects of ethanol treatment on inducible nitric oxide (NO) synthase pathway from lipopolysaccharide- or interleukin-1 beta-treated cultured rat blood-brain barrier cell line (rat brain endothelial 4 cells: RBE4 cells). Cells were lipopolysaccharide- or interleukin-1 beta-treated with or without ethanol (50, 100 or 200 mM) for 16 or 24 h. Inducible NO synthase activity and mRNA expression were measured using Griess reaction and reverse transcription-polymerase chain reaction (RT-PCR) respectively.

Functional expression of P-glycoprotein in an immortalised cell line of rat brain endothelial cells, RBE4.

The presence of P-glycoprotein in the cell plasma membrane limits the penetration of many cytotoxic substances into cells that express the gene product. There is considerable evidence also to indicate that P-glycoprotein is expressed as part of the normal blood-brain barrier in the luminal membranes of the cerebral capillary endothelial cells, where it presumably performs a protective function for the brain. This report describes the functional expression of P-glycoprotein in an immortalised cell line, RBE4, derived from rat cerebral capillary endothelial cells.

Extracting one-dimensional wavelet features with a diffractive optical inner-product transform.

A diffractive optical element (DOE) that performs a wavelet transform on one-dimensional signals is presented. The DOE performs an inner product between the input image and a set of wavelet basis functions. The input image is displayed in a spatial light modulator.

Cisplatin-based neoadjuvant chemotherapy and combined resection for ethmoid sinus adenocarcinoma reaching and/or invading the skull base.

Objective: To review our experience with cisplatin-based neoadjuvant chemotherapy before en bloc resection via a combined neurosurgical and transfacial approach for ethmoid sinus adenocarcinoma reaching and/or invading the skull base.

Design: Case series.

Setting: A tertiary care center and university teaching hospital.

High-resolution Fourier spectrometry of N(2)(+).

A new perturbation analysis of the first negative system B(2)Σ(u)(+) ? X(2)Σ(g)(+) of the (14)N(2)(+) ion is performed based on spectra excited both at low and high temperatures by the use of either a hollow-cathode or a Pointolite lamp. Preliminary results are given for a deperturbation of the B(2)Σ(u)(+) (ν = 0, ν = 1) levels. Deperturbed molecular constants and parameters that describe the B(2)Σ(u)(+) ~ A(2)∏(u) interaction are derived.

Synergistic stimulation of gamma-glutamyl transpeptidase and alkaline phosphatase activities by retinoic acid and astroglial factors in immortalized rat brain microvessel endothelial cells.

The immortalized rat brain microvessel endothelial cell line RBE4 was used to investigate the in vitro regulation of two blood-brain barrier specific enzymes, gamma-glutamyl transpeptidase (GTP) and alkaline phosphatase (ALP). The effects of bFGF, astroglial factors, and retinoic acid (a cell differentiation agent) on GTP and ALP activities were separately or simultaneously studied in order to define optimal culture conditions for induction of these two specific enzymes of the blood-brain barrier. In the present study, a phenotypically distinct subpopulation of endothelial cells has been shown to develop from confluent cobblestone monolayers of RBE4 immortalized cerebral endothelial cells.

Functional and binding characteristics of long-acting beta 2-agonists in lung and heart.

Salmeterol and formoterol, two new long-acting beta 2-agonists were equipotent (values of negative log molar concentration eliciting half-maximal effect [pD2] 9.2 +/- 0.03 and 8.

[Pulmonary emphysema: surgical indications].

Surgery for pulmonary emphysema, with the exception of lung transplantation, is limited at present to resection of the emphysematous areas. The resection of a unique bulla within an otherwise healthy parenchyma can be indicated in case of complications but rarely in asymptomatic patients. When the bullae are large (i.