Acute stroke: usefulness of early CT findings before thrombolytic therapy.

PURPOSE: To determine whether the extent of subtle parenchymal hypoattenuation detected on computed tomographic (CT) scans obtained within 6 hours of ischemic stroke is a factor in predicting patients' response to thrombolytic treatment. MATERIALS AND METHODS: The baseline CT scans of 620 patients, who received either recombinant tissue plasminogen activator (rt-PA) or a placebo, in a double-blind, randomized multicenter trial were prospectively evaluated and assigned to one of three categories according to the extent of parenchymal hypoattenuation: none, 33% or less (small), or more than 33% (large) of the middle cerebral artery territory. The association between the extent of hypoattenuation on the baseline CT scans and the clinical outcome in the placebo-treated and the rt-PA-treated groups after 3 months was analyzed. RESULTS: In 215 patients with a small hypoattenuating area, treatment increased the chance of good outcome. In 336 patients with a normal CT scan and in 52 patients with a large hypoattenuating area, rt-PA had no beneficial effect but increased the risk for fatal brain hemorrhage. CONCLUSION: The response to rt-PA in patients with ischemic stroke can be predicted on the basis of initial CT findings of the extent of parenchymal hypoattenuation in the territory of the middle cerebral artery.

[Comparative studies on the bioavailability of nicergoline from two different steady-state preparations]. / Vergleichende Untersuchungen zur Bioverfügbarkeit von Nicergolin aus zwei unterschiedlichen Darreichungsformen im Steady State.

Comparative Studies on the Bioavailability of Nicergoline from Two Different Preparations in Steady State The bioavailability of nicergoline (CAS 27848-84-6) in a new 30 mg tablet and a 10 mg dragee formulation (Sermion) was evaluated under steady state conditions in 18 healthy male volunteers between the age of 21 and 37 years. During the run-in phase, the volunteers received on 7 consecutive days 30 mg nicergoline either 1 x 30 mg/d tablet (test substance) or 3 x 10 mg dragees (reference). On day 8, after intake of 1 x 30 mg in a 24 h interval or 1 x 10 mg in a 8 h interval respectively, the plasma concentrations of the nicergoline metabolite 10-methoxy-6-methyl-ergoline-8 beta-methanol (MDL) were measured. The area under the plasma concentrations in the 24 h interval after administering the 30 mg tablet was not 3 times greater as to be expected; it was by a factor of 4 significantly greater than the area under the curve of the 10 mg dragee in the 8 h interval. Therefore, nicergoline has a higher availability in the 30 mg tablet than in the 10 mg dragee form. Both formulations were equally well tolerated.

Electrophysiological follow up of experimental allergic neuritis mediated by a permanent T cell line in rats.

Acute experimental allergic neuritis (EAN) was produced in Lewis rats by transfer of lymphocytes from a permanent T cell line specific for bovine P2 protein. In 3 groups of rats receiving 10(4), 10(5) and 10(6) total injected P2-specific lymphocytes, respectively, the time course of illness was followed by measuring several electrophysiological parameters including the H reflex or F wave and lumbospinal somatosensory evoked potentials (SEP). The severity and time course of both the electrophysiological and clinical (e.g., loss of weight and development of paresis) parameters of illness depended on the number of injected lymphocytes. Lower numbers of injected cells were correlated with a later onset and less severe symptoms as well as with an earlier and more complete recovery. According to clinical observation EAN mediated by lymphocytes is a monophasic illness. According to our electrophysiological measurements, however, the disease can be described by the following successive stages: (a) an early stage of hyperexcitability; (b) a stage of acute partial conduction block; (c) 14 days later a stage of maximal demyelination; and (d) a recovery phase. Although demyelination is the prominent feature of the disease, axonal degeneration also occurs to an extent directly related to the number of cells injected. Degeneration was not observed in rats from the group with the lowest number (10(4] of injected lymphocytes.

Free amino acid pattern of cerebrospinal fluid in amyotrophic lateral sclerosis.

The concentrations of 23 amino acids (AA) were measured in CSF of patients with Amyotrophic Lateral Sclerosis (ALS). A micro-method with picomole sensitivity was used. Compared with healthy controls no significant alterations of single or total AA concentrations were found. These results contrast with data published in a previous study and will be discussed in detail.

Astrocytes support incomplete differentiation of an oligodendrocyte precursor cell.

Glial fibrillary acidic protein-positive astrocytes, but not neurons or fibroblasts, support the differentiation of an oligodendroglial precursor cell expressing O4 antigen and vimentin into an O4 antigen-positive, but vimentin-negative oligodendrocyte. Further maturation into galactocerebroside (O1)-positive oligodendrocytes is, however, not achieved under the culture conditions used, neither in the presence of astrocytes nor neurons.

Immunoselection of oligodendrocytes by magnetic beads. I. Determination of antibody coupling parameters and cell binding conditions.

Oligodendrocytes from early postnatal mouse cerebellum were isolated using polyacrylamide-coated magnetic beads carrying monoclonal antibody to 04 cell surface antigen. Oligodendrocytes were enriched to a purity of 91 +/- 4% starting from a mixed cell population containing approximately 1.5% antigen-positive oligodendrocytes. Viability of 04 antigen-positive oligodendrocytes was approximately 90% as judged by exclusion of trypan blue. Oligodendrocytes were recovered after detachment from the beads with a yield of 19 +/- 6% and after collection by centrifugation onto glass coverslips with yields of approximately 6% of all 04 antigen-positive cells. The final cell yield of oligodendrocytes is approximately 8 x 10(5) cells/gram fresh cerebellar tissue.