[Intramedullary tumors. Results of a national investigation in private neurosurgery]. / Les tumeurs intramédullaires. Résultat d'une enquête nationale en neurochirurgie libérale.

UNLABELLED: The frequency of intramedullary tumors is 0.5 cases per year for 100,000 inhabitants. The study reported herein was a retrospective study conducted from January 1985 to September 2007. MATERIAL: Seventy-nine cases were distributed in the following manner: ependymomas, 38; astrocytomas, 22; oligodendrogliomas, four; gangliogliomas, two; hemangioblastomas, 10 (nine sporadic cases and one case of Von Hippel-Lindau disease); primitive melanoma, one; and intramedullary neurinomas, two. Three patients were lost to follow-up and 10 patients died. METHOD: All patients were explored using MRI and were operated using a microsurgical technique. Tumor removal was complete in the cases of ependymoma and hemangioblastoma and subtotal in the cases of astrocytoma. RESULTS: Ependymoma: 38 cases with three cases of ependymoblastoma. Mean age: 47 years (range, 17-74 years); 17 males and 21 females. Diagnostic delay: less than one year, 11; one year, 15 cases; two years, nine cases; three years, three cases. Seven recurrences with one 35 years after a prior removal. Localizations: cervical and cervicodorsal, 19; dorsal, ten; dorsolumbar, seven; holomedullary, one. Number of levels concerned: 5-12 (with the cysts associated). Mean follow-up was 10 years (range, two months to 35 years). Patients stabilized, 19; worse, six; improved, nine. Patients deceased: four, one by suicide, three cases of ependymoblastoma (survival, seven months). Astrocytomas: 22 cases, with 14 cases of astrocytoma, two pilocytic astrocytoma, four malignant astrocytoma, and two glioblastoma. Mean age: 44 years (range, 22-73 years); 14 males and eight females. Diagnostic delay: malignant tumors, one to nine months; low grades; three to six years (range, eight months to 25 years). Number of levels concerned: two to eight. Mean follow-up: seven years (range, six months to 10 years). Stabilized patients: 13; worse, five; deaths, four. Oligodendroglioma: four cases. Mean age: 58 years; two males and two females. Diagnostic delay: 10months. Localization: cervical, three; dorsal, one. Oligodendroglioma A, two; B, two. Results: two cases stabilized, one case with recurrence, and one patient deceased. Ganglioglioma: two. Both cases were associated with scoliosis. Recurrence in the eighth month and two years for the second case. One patient died. Hemangioblastoma: 10 cases, nine sporadic and one case of Von Hippel-Lindau disease. Nine cervical localizations, one on the medulla cone. Mean age: 45 years (range, 11-54 years); eight males and two females. Total removal in nine cases. One case of recurrence seven years after a prior surgery and operated a second time with no recurrence after 10 years of follow-up. Intramedullary neurinomas: two cases with a total removal and 15 years of follow-up. Primitive melanoma: one case with mediothoracic location. Treatment with surgery plus radiotherapy. Follow-up, seven years without recurrence. CONCLUSION: Total removal of the intramedullary tumors is a challenge. In cases of removal, the risk of worsening status is 18-19.5%. Subtotal or incomplete removal 27-40% risk of recurrence.

Oxidase activity of the acyl-CoA dehydrogenases.

The medium chain acyl-CoA dehydrogenase catalyzes the flavin-dependent oxidation of a variety of acyl-CoA thioesters with the transfer of reducing equivalents to electron-transferring flavoprotein. The binding of normal substrates profoundly suppresses the reactivity of the reduced enzyme toward molecular oxygen, whereas the oxidase reaction becomes significant using thioesters such as indolepropionyl-CoA (IP-CoA) and 4-(dimethylamino)-3-phenylpropionyl-CoA (DP-CoA). Steady-state and stopped-flow studies with IP-CoA led to a kinetic model of the oxidase reaction in which only the free reduced enzyme reacts with oxygen (Johnson, J. K., Kumar, N. R., and Srivastava, D. K. (1994) Biochemistry 33, 4738-4744). We have tested their proposal with IP-CoA and DP-CoA. The dependence of the oxidase reaction on oxygen concentration is biphasic with a major low affinity phase incompatible with a model predicting a simple Km for oxygen of 3 microM. If only free reduced enzyme reacts with oxygen, increasing IP-CoA would show strong substrate inhibition because it binds tightly to the reduced enzyme. Experimentally, IP-CoA shows simple saturation kinetics. The Glu376-Gln mutant of the medium chain dehydrogenase allows the oxygen reactivity of complexes of the reduced enzyme with IP-CoA and the corresponding product indoleacryloyl-CoA (IA-CoA) to be characterized without the subsequent redox equilibration that complicates analysis of the oxidase kinetics of the native enzyme. In sum, these data suggest that when bulky, nonphysiological substrates are employed, multiple reduced enzyme species react with molecular oxygen. The relatively high oxidase activity of the short chain acyl-CoA dehydrogenase from the obligate anaerobe Megasphaera elsdenii was studied by rapid reaction kinetics of wild-type and the Glu367-Gln mutant using butyryl-, crotonyl-, and 2-aza-butyryl-CoA thioesters. In marked contrast to those of the mammalian dehydrogenase, complexes of the reduced bacterial enzyme with these ligands react with molecular oxygen at rates similar to those of the free protein. Evolutionary and mechanistic aspects of the suppression of oxygen reactivity in the acyl-CoA dehydrogenases are discussed.

Shunt failure in adult hydrocephalus: flow-controlled shunt versus differential pressure shunts--a cooperative study in 289 patients.

BACKGROUND: In order to assess the efficiency of flow-controlled shunts in reducing shunt failure in the treatment of adult hydrocephalus (with a special focus on overdrainage complications), a series of 289 patients was analyzed through a retrospective and comparative study performed in three neurosurgical departments. METHODS: A group of 142 adult patients suffering from hydrocephalus were operated on using a conventional differential pressure (DP) shunt and compared with a group of 147 adult patients operated on using flow-controlled (FC) system (Orbis-Sigma, Cordis). Only the first complication, which required a surgical revision within the first 2 years after shunt implantation, was taken into account for each patient and analyzed using life-table methods. RESULTS: The actuarial risk of shunt infection in the two groups is respectively 8.3% and 10.9% at 1 year (nonsignificant difference). The actuarial risk of mechanical complications at 1 year is 38% for the DP patients and 10% for the FC patients (p = 0.0001); this difference is largely due to a decrease of complications related to overdrainage phenomenon (14/142 subdural collections were observed in the DP group versus 1/147 in the FC group) (p = 0.0001). CONCLUSION: The conclusion of this cooperative and retrospective study is that the use of a flow-controlled system decreases the risk of mechanical complications related to the hydrodynamic properties of the shunts used in the treatment of adult hydrocephalus, especially those related to overdrainage.

Electron-transferring flavoprotein from pig and the methylotrophic bacterium W3A1 contains AMP as well as FAD.

Electron-transferring flavoproteins from pig kidney and from the methylotrophic bacterium W3A1 have been found to contain one molecule of AMP in addition to the single FAD molecule bound to these heterodimers. The nucleotide was identified by spectral and chromatographic methods and via its behavior toward adenylate kinase and alkaline phosphatase. The role of this additional non-redox active prosthetic group in electron transferring-flavoprotein is at present unclear.

[Treatment of chronic hydrocephalus in adults by flow-regulated shunt. Apropos of a series of 46 patients]. / Traitement de l'hydrocéphalie chronique de l'adulte par dérivation à débit régulé. A propos d'une série de 46 patients.

46 patients, 24 males and 22 females (mean age: 68.3 years), with chronic hydrocephalus were operated on by a variable-resistance, flow-regulated shunt. The selecting criteria before surgery were essentially clinical (association of gait disturbances, dementia and urinary incontinence, positive lumbar puncture withdrawal test) in consideration with the retrospective and cooperative study of this series. Hydrocephalus had an etiology in 23 cases (50%): 4 cases of trauma (8%), 9 cases of tumors (20%), 9 cases of subarachnoid haemorrhage (20%) and 1 case of infection (2%). The average follow-up is 17 months (median: 12 months). 20 patients (43.5%) have an excellent result (normal life), 16 patients (34.8%) have a good result (residual symptomatology compatible with a self-governing life), 5 patients (10.9%) have a poor result (residual symptomatology non compatible with a self-governing life), 2 patients (4.3%) have a bad result (unchanged symptomatology). 3 patients died after the surgical procedure. 3 patients had an infectious complication of their shunt (actuarial risk of infectious complication at one year and a half: 7%). 2 patients presented a non infectious complication, one chronic subdural hematoma and one bad insertion of the proximal catheter (actuarial risk of mechanical complication at one year and a half: 4.4%).

[Intradural extramedullary neuro-enteric cysts without associated malformation. 3 cases with magnetic resonance imaging]. / Kystes neurentériques intraduraux extramédullaires sans malformation associée. Trois cas avec imagerie en résonance magnétique.

We report 3 cases of extramedullary neurenteric cyst without associated dysraphic lesions. One of the cases had an ultrastructural study. Magnetic resonance imaging provided a preoperative diagnosis. The embryogenesis of neurenteric cysts, their main clinical aspects and their surgical treatment are reviewed.

[Lumboperitoneal shunt and normal pressure hydrocephalus in elderly subjects]. / Dérivation lombo-péritonéale et hydrocéphalie à pression normale des sujets agés.

Forty six patients who had normal pressure hydrocephalus (NPH) and who presented 2 or more of the 5 following preoperative signs: dementia with gait disturbances and urinary incontinence, gait disturbance as first sign, known etiology, positive lumbar puncture withdrawal test, presence of periventricular hypodensity on CT and absence of visible cerebral sulci, were treated by lumboperitoneal shunt. Postoperative results were evaluated at 1 month, 6 months and 1 year with 60.6 p. 100 of good results. Complications of LP shunts (26 p. 100) were mild and did not compromise the outcome. We emphasize the necessity of clinical selecting criteria before surgery and the value of LP shunt in the treatment of NPH.

[Intraventricular neurocysticercosis. Apropos of 3 cases]. / Neurocysticercose intraventriculaire. A propos de trois observations.

Cysticercosis cerebri is a rare neurological diagnosis in France. It is classically divided into four types: intraparenchymal, basilar cisternal, ventricular and diffuse. Three cases of intraventricular cysticercosis are reported. All patients had symptoms of increased intracranial pressure due to hydrocephalus and the authors emphasize the necessity of investigating for possible neurocysticercosis patients from endemics areas who presented such a clinical picture. They emphasize the interest of the E.L.I.S.A. test in order to detect anticysticercosis antibodies in blood and C.S.F. and the interest of Magnetic Resonance Imaging in order to visualise the cysts. Praziquantel do not affect intraventricular cysts and the surgical treatment is necessary to remove the cysts because the presence of an intraventricular parasite indicates an important risk of acute hydrocephalus and secondary of ependymitis source of irreversible neurological damages.