The effects of 4-aminopyridine on cognitive function in patients with multiple sclerosis: a pilot study.

4-Aminopyridine (4-AP) has a favorable effect on the disability of certain patients with MS. We investigated the effect of 4-AP on neuropsychological performance in 20 MS patients using a randomized, double-blind, placebo-controlled, crossover design. Although there was a trend for improved performance with 4-AP for two of the tests, we could not demonstrate significant effects of 4-AP on cognitive function.

Functional defects in peripheral blood T cells of multiple sclerosis patients. Diminished in vitro responsiveness in accessory cell dependent activation systems.

Function and phenotype of peripheral blood (PB) T cells in multiple sclerosis (MS) patients were analyzed. In whole blood cultures, T cell proliferation of multiple sclerosis (MS) patients, using soluble CD3 mAb and CD2 mAb as stimulants, was reduced in comparison to healthy controls. A similar difference was seen when isolated PBMC were tested after stimulation with soluble CD3 mAb.

4-aminopyridine in the treatment of patients with multiple sclerosis. Long-term efficacy and safety.

Objective: To study the long-term efficacy and safety of 4-aminopyridine in patients with multiple sclerosis.

Design: Case series, follow-up varying from 6 to 32 months.

Setting: University referral center.

Magnetic resonance evaluation of disease activity during pregnancy in multiple sclerosis.

We followed two women with MS during pregnancy by means of serial unenhanced MR imaging. On each follow-up image, we assessed the number of new or enlarging lesions. Both women showed a decrease in MR disease activity during the second half of pregnancy and a return of MR disease activity to prepregnancy levels in the first months postpartum.

Therapeutic effect of the D2-dopamine agonist bromocriptine on acute and relapsing experimental allergic encephalomyelitis.

We examined the effect of bromocriptine (BCR) treatment on the duration and severity of neurological symptoms of acute experimental allergic encephalomyelitis (EAE), an animal model for demyelinating diseases, particularly multiple sclerosis. To mimic the clinical situation, BCR treatment was started after the onset of clinical signs. Furthermore, the effect of BCR treatment on the course of a chronic relapsing form of EAE was studied.

Fatigue, sleep disturbances and circadian rhythm in multiple sclerosis.

The aim of this study was to investigate whether fatigue and sleep disturbances in multiple sclerosis (MS) patients might be due to disrupted circadian sleep wake regulation. Actigraphy and a multiple sleep latency test (MSLT) were performed in 16 MS patients with both prominent sleep complaints and fatigue. Actigraphy scores did not differ from control values, whereas sleep onset latency values were altered in subgroups of MS patients.

Minor myelin proteins can be major targets for peripheral blood T cells from both multiple sclerosis patients and healthy subjects.

T cell recognition of myelin is likely to play a role in the pathogenesis of multiple sclerosis. Predominant protein components of myelin, myelin basic protein (MBP) and proteolipid protein (PLP), have been considered as possibly relevant autoantigens, especially since both proteins are encephalitogenic in various laboratory animals. It has remained unclear, however, to what extent the numerous minor proteins contained in myelin may serve as targets for human T cell responses to myelin.

4-Aminopyridine in patients with multiple sclerosis: dosage and serum level related to efficacy and safety.

In a recent randomized, double-blind, placebo-controlled crossover trial, we demonstrated efficacy of 4-aminopyridine (4-AP) in improving disability of patients with multiple sclerosis (MS). Here we describe the relationship between dosage, serum level, efficacy, and safety of intravenously and orally administered 4-AP in the same group of 70 MS patients. After both intravenous and oral administration there was a significant relationship between serum levels and 4-AP doses used (p < 0.

The significance of in-situ Ia antigen expression in the pathogenesis of autoimmune central nervous system disease.

Major histocompatibility class II antigen (Ia) expression is thought to play an important role in the pathogenesis of autoimmune central nervous system (CNS) disease. It has been suggested that Ia expression within the CNS might be sufficient to induce experimental allergic encephalomyelitis (EAE). The expression of Ia antigen in the CNS was studied during the natural course of both acute and chronic relapsing EAE.

4-Aminopyridine induces functional improvement in multiple sclerosis patients: a neurophysiological study.

This study reports on the neurophysiological measurements that were performed in the context of a randomized, double-blind, placebo-controlled, cross-over study with intravenously administered 4-aminopyridine (4-AP) in 70 patients with definite multiple sclerosis (MS). A beneficial effect of 4-AP was found for both visual evoked response and eye movement registration parameters. This study extends the experimental data obtained on animal nerve fibers, showing that 4-AP can improve impulse conduction in demyelinated nerve, to clinical data which indicate that 4-AP induces an objective improvement in the central nervous system function in MS-patients.

Multiple sclerosis: some possible therapeutic opportunities.

Multiple sclerosis (MS) is a human disease characterized by chronic demylination in the brain caused by immunological mechanisms involving T lymphocytes and macrophages. Recently developed models of chronic relapsing forms of experimental allergic encephalomyelitis, sharing many of the clinical and pathological features of MS, and new discoveries of efficient autoregulatory mechanisms intrinsic to the immune system, have suggested new possibilities for therapeutic intervention in MS. Moreover, recent data support the concept that the immune system is exposed to a broad framework of regulation, including neuroendocrine control.

The effect of 4-aminopyridine on clinical signs in multiple sclerosis: a randomized, placebo-controlled, double-blind, cross-over study.

To find out whether treatment with 4-aminopyridine is beneficial in multiple sclerosis (MS), 70 patients with definite MS entered into a randomized, double-blind, placebo-controlled, cross-over trial in which they were treated with 4-aminopyridine and placebo for 12 weeks each (maximum dose, 0.5 mg/kg of body weight). The estimated effect of the treatment as measured with the Kurtzke expanded disability status scale, which was the main evaluation parameter, was 0.

Quantitative measurement of vibratory sense and temperature sense in patients with multiple sclerosis.

In this study the vibratory perception threshold (VPT) and the thermal discrimination threshold (TDT) were measured in 33 patients with clinically definite multiple sclerosis (MS). VPT values were abnormal in a majority of MS patients (68%). There was no relation between VPT and the severity of the disease.

Pupillary light reflex latency in patients with multiple sclerosis.

In 46 patients with definite multiple sclerosis (MS) the direct and indirect pupillary light reflex latency (PLRL) and visual evoked potential (VEP) latency of the P100 were measured for each eye separately. The PLRL was measured at both photopic and scotopic illuminance level, using an infrared light reflection technique (IRIS). On average the PLRL increased at the scotopic illuminance level as compared with the photopic (P less than 0.

Determination of 4-aminopyridine in serum by solid-phase extraction and high-performance liquid chromatography.

An assay for the determination of 4-aminopyridine in serum has been developed using 3,4-diaminopyridine as internal standard and reversed-phase high-performance liquid chromatography with detection at 244 nm. A mobile phase of acetonitrile-methanol-ethanol-1% ammonium carbonate (75:10:10:5) provided excellent separation of both compounds. Samples were extracted on solid-phase columns.

Evaluation of the visual system in multiple sclerosis: a comparative study of diagnostic tests.

In 22 patients with clinically definite multiple sclerosis (MS) who were without visual symptoms and had a visual acuity of at least 1.0 in both eyes at the time of measurement, the following tests were performed to detect subclinical lesions in the visual system: visual evoked potential (VEP), contrast sensitivity test (CS), flight of colours test (FOC), colour vision test (Ishihara plates) (CV) and the pupillary light reflex (PLR). VEP was abnormal in 81.

Increased visual impairment after exercise (Uhthoff's phenomenon) in multiple sclerosis: therapeutic possibilities.

The Uhthoff symptom, a transient impairment of visual function after exercise, is demonstrated in 2 multiple sclerosis patients. Following exercise, impairment of visual function, as documented most clearly by the testing of contrast sensitivity, was less obvious after body surface cooling and after treatment with orally administered 4-aminopyridine. It is hypothesized that both treatment modalities improve the nerve conduction safety factor and thereby prevent the occurrence of a conduction block, which is believed to be the mechanism underlying the Uhthoff symptom.

Elevated levels of a soluble form of the T cell activation antigen CD27 in cerebrospinal fluid of multiple sclerosis patients.

The expression of the T cell membrane molecule CD27--a molecule that has recently been shown to belong to the nerve growth factor receptor superfamily--is strongly increased after activation of T lymphocytes via the T cell receptor/CD3 complex. In addition, activated cells release a 28-32 kDa soluble form of CD27 in their supernatant which can also be detected in serum and urine of healthy individuals. In this study we show that levels of soluble (s) CD27 are significantly elevated in cerebrospinal fluid (CSF) of multiple sclerosis (MS) patients and of patients and of suffering from other inflammatory neurological diseases (OIND), whereas increased levels of sCD25 (soluble interleukin-2 receptor) were only found in CSF of patients with OIND.

Cardiovascular autonomic function in multiple sclerosis.

In this study blood pressure (BP) and heart rate (HR) responses to standing and HR responses to deep breathing were assessed in 34 patients with clinically definite multiple sclerosis (MS) and 63 healthy subjects. Normal ranges, which were clearly age related for both HR responses, were obtained. The BP response to standing was abnormal in 13% of the MS patients, these patients demonstrating significant postural hypotension.