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N Canal

Publications and source records attributed to N Canal.

At least 73 records · Page 4Linked to original sources
PubMed1992

In vivo modulation of myelin gene expression by human recombinant IL-2.

We treated adult mice with human recombinant interleukin-2 (IL-2) and determined the expression of the genes encoding for the major central and peripheral myelin proteins. In the CNS, myelin basic protein (MBP) and myelin-associated glycoprotein (MAG) mRNA levels were the same both in IL-2-treated and in control mice. Proteolipid protein (PLP) transcript was decreased in IL-2-treated animals when compared to controls. In the PNS, the messages for the glycoprotein P0 and for MBP were markedly increased in IL-2-treated animals when compared to controls.

Animals↗
PubMed1992

A clinical, electrophysiological, morphological and immunological study of chronic sensory neuropathy with ataxia and paraesthesia.

We have observed 9 patients (8 men and 1 woman), 58 to 77 years of age with neuropathy with only sensory symptoms and insidious onset. Five of them (4 men and 1 woman) aged 65 to 77 years, had normal serum electrophoretic profiles, while the others (all men), 58 to 74 years, had IgM monoclonal gammopathy of undetermined significance (MGUS). Clinical data were consistent with a sensory neuropathy affecting predominantly the kinesthetic sense (position and vibration sensation). The electrophysiological data indicated predominant sensory axonal neuropathy. Morphological data confirmed the primary axonal damage. Western immunoblot showed that the IgG from a patient without MGUS reacted with a 55 kD protein of dorsal root ganglion homogenate. Three of four patients with IgM MGUS were serum reactive against chondroitin sulfate C (ChS-C) in double immunodiffusion. After absorption with ChS-C the monoclonal peak completely disappeared from two patients and was decreased in the third patient. Our data indicate that immunological abnormalities are part of the pathogenesis for a subgroup of chronic neuropathy with only sensory symptoms.

Aged↗
PubMed1991

Polyneuropathy associated with IgA monoclonal gammopathy: a hypothesis of its pathogenesis.

We describe three patients with chronic progressive polyneuropathy associated with IgA monoclonal gammopathy. Two patients had a prominent sensory neuropathy and one had a prominent motor neuropathy. Sural nerve biopsies showed axonal degeneration in all cases. In immunocytochemical studies patients' IgG immunostained axons. By Western immunoblot a band of IgG reactivity with an axonal protein of 66 kDa was found. No band of IgA and IgM were found. We suggest the possibility that the IgA monoclonal protein may act as a stimulating factor of preexisting B cell clones eliciting an immune reaction against nerve antigens.

Aged↗
PubMed1991

Neurophysiological study of the effect of combined kidney and pancreas transplantation on diabetic neuropathy: a 2-year follow-up evaluation.

Previous study have reported a significant improvement of peripheral neuropathy following combined pancreas and kidney transplantation attributed to improvement of blood glucose control by some authors and to elimination of uraemia by others. To asses the specific role of uraemia and hyperglycaemia in neuropathy, 16 diabetic uraemic patients with combined pancreas and kidney transplantation were compared to 9 diabetic patients with a renal graft only. Neurophysiological studies of peripheral neuropathy included ulnar and deep peroneal nerve motor conduction velocity, median and sural nerve sensory conduction velocity were performed at baseline and 1 and 2 years after transplantation. One year after transplantation mean nerve conduction velocity significantly improved in both groups. However, changes were statistically significant in the kidney-pancreas group only. At the 2 year follow-up nerve conduction velocity had increased further in the pancreas-kidney group only. These data suggest that improvement of nerve conduction velocity following pancreas and kidney transplantation is predominantly due to the long-term euglycaemic state.

Adult↗
PubMed1991

Axonal neuropathy in a patient with monoclonal IgM kappa reactive with Schmidt-Lantermann incisures.

We report a patient with a progressive, predominantly sensory neuropathy and a IgM kappa M-protein that binds to Schmidt-Lantermann incisures. A sural nerve biopsy showed primary axonal damage and IgM deposits at Schmidt-Lantermann incisures were seen by direct immunoperoxidase. Serum from the patient injected into rat sciatic nerve reacts with the incisures as with those in the patient's nerve. The IgM kappa M-protein reacts with chondroitin sulfate C and binds to a broad nerve protein band with a mobility of between 170 and 118 kDa. Peripheral neuropathy may be related to the M-protein, which had immunocytochemical reactivity not previously described for patients with polyneuropathy and IgM monoclonal gammopathy.

Axons↗
PubMed1991

Autoantibodies to glutamic acid decarboxylase (GAD) detected by an immuno-trapping enzyme activity assay: relation to insulin-dependent diabetes mellitus and islet cell antibodies.

It has recently been proposed that the islet 64,000 Mr protein autoantigen (64K) of insulin-dependent diabetes mellitus (IDDM) is glutamic acid decarboxylase (GAD). We evaluated, by means of a newly developed immunotrapping enzyme activity assay (ITEAA), the prevalence of circulating GAD-autoantibodies (Ab) in a large population of IDDM patients (n = 168), blood donors (n = 87) and non-diabetic autoimmune patients (n = 40). The latter two groups were used as controls. Overall, GAD-Ab were found in 22% of IDDM patients, but in none of the two control groups (P = 0.007). These specificities were invariably associated with islet cell antibodies (ICA) (31.6% in IDDM with ICA vs 0 in IDDM without ICA, P = 0.0001), and this prevalence was higher in sera with high titer ICA (54.5% in IDDM with ICA greater than 80 JDF-units vs 22.6% of IDDM with ICA 5-80 JDF units; P = 0.002). Moreover, GAD-Ab were associated with the female sex (P = 0.002) and the concomitant presence of thyroid and/or gastric antibodies (P = 0.002). No correlation was observed between GAD-Ab and age of the patients, duration of IDDM, or associated non-organ specific antibodies. Our study indicates that GAD-Ab measured by ITEAA are: (1) detected in a proportion of IDDM patients; (2) strongly associated with ICA; (3) preferentially found in IDDM female patients with autoimmune polyendocrine serology; and (4) detected with lower frequency than that reported for 64K-Ab in IDDM.

Adolescent↗
PubMed1991

Paraclinical tests in acute-onset optic neuritis: basal data and results of a short follow-up.

Up to now it is still doubtful whether there is a real risk of developing multiple sclerosis (MS) after initial monosymptomatic optic neuritis (ON). In this study we evaluated 43 patients with isolated acute-onset ON, in order to demonstrate the presence of oligoclonal bands (OBs) in the cerebrospinal fluid (CSF) and any additional clinically silent central nervous system (CNS) lesions. All examinations were performed from 5 days to 4 months (mean 43 days), from the onset of visual disturbances. Brain magnetic resonance imaging (MRI) detected white matter areas with increased signal in 21 patients (49%), while somatosensory and brainstem auditory evoked potentials revealed CNS abnormalities in only 5 patients (12%). OBs were present in the CSF of 20 patients (46%). Visual evoked potentials were abnormal in 39 patients (91%). Seven out of the 37 patients (19%) with at least one year follow-up, (mean duration of the follow-up = 32 months, range = 12-74), developed clinically definite MS (CDMS). All 7 patients had positive brain MRI and 6 had positive CSF examination at the basal evaluation. Our data suggest that MRI and CSF-OBs are the most reliable means of identifying patients with isolated ON who subsequently develop CDMS. They may therefore have a predictive value in defining MS risk.

Acute Disease↗
PubMed1991

ACTH and cortisol secretion in patients with Alzheimer's disease.

The "glucocorticoid cascade hypothesis" for pathological ageing of the brain is supported by strong experimental data, but the clinical correlates are far less clear. The basal ACTH and cortisol secretion have been studied before and after the dexamethasone suppression test in patients in the early stages of clinically probable Alzheimer's disease and in controls, and the results were all normal. These findings do not support the hypothesis that the pathological brain ageing of Alzheimer's type is caused by hyperactivity of the pituitary-adrenal axis.

Adrenocorticotropic Hormone↗
PubMed1991

Effect of L-alpha-glyceryl-phosphorylcholine on amnesia caused by scopolamine.

The present study was carried out to test the effects of L-alpha-glycerylphosphorylcholine (L-alpha-GFC) on memory impairment induced by scopolamine in man. Thirty-two healthy young volunteers were randomly allocated to four different groups. They were given a ten day pretreatment with either L-alpha-GFC or placebo, p.o., and on the eleventh day either scopolamine or placebo, i.m. Before and 0.5, 1, 2, 3, and 6 h after injection the subjects were given attention and mnemonic tests. The findings of this study indicate that the drug is able to antagonize impairment of attention and memory induced by scopolamine.

Adult↗
PubMed1990

Prevalence of dementia in adult patients with trisomy 21.

Neuropathological lesions characteristic of Alzheimer's disease (AD) are found in all the brains of patients with trisomy 21 who die after age 40 years. However, clinical signs of AD are much less frequent in these patients. Previous studies indicate prevalence figures ranging from 15% to 51% of adult patients. We report here on the prevalence rate of dementia in a population of adult patients with trisomy 21 with mild retardation living at home. For all these patients accurate and reliable anamnestic data could be obtained from parents and caregivers. All underwent neurological examination, cognitive testing, and, if necessary, further bioimaging and neurophysiological studies. Dementia was diagnosed according to clinical NINCDS/ADRDA criteria slightly modified. Dementia was found in 9 of 50 (18%) patients age 20-52 years, but its prevalence increased from 0 in the age group 20-29, to 33% in the age group 30-39, and to 55% in the age group 40-52. All the demented patients had signs of brain atrophy on CT scans and slow EEGs. Dementia is an important problem for patients with trisomy 21 older than age 30 years.

Adult↗
PubMed1990

Acute- and insidious-onset myelopathy of undetermined aetiology: contribution of paraclinical tests to the diagnosis of multiple sclerosis.

Brain magnetic resonance imaging (MRI), multimodality evoked potentials (EPs) and cerebrospinal fluid examination were performed in 42 patients with myelopathy of undetermined aetiology in order to detect abnormalities usually related to multiple sclerosis (MS). Patients were divided into three groups: insidious-onset myelopathy with only motor signs (group A; 11 patients), with both motor and sensory signs (group B; 18 patients) and acute-onset myelopathy (group C; 13 patients). Multiple brain MRI lesions were found in 18 patients (2 of group A, 13 of group B and 3 of group C). Another 7 patients had a single white-matter lesion. Visual EPs were abnormal in 21 and brain-stem auditory EPs in 12 patients. Paraclinical tests supported the diagnosis of MS in 25 patients (60%) by showing subclinical brain abnormalities. Oligoclonal bands were found in 16 of these 25 patients. The findings strongly suggest a diagnosis of MS in the patients of group B.

Acute Disease↗
PubMed1990

Spectral analysis of short-term heart rate variability in diabetic patients.

Spectral analysis of short term R-R variability estimated by autoregressive modelling is a recently developed method for the evaluation of cardiovascular autonomic function. This new test also allows to study the interaction on heart rate variability of parasympathetic and sympathetic system. The sensitivity of the method for detection of cardiovascular autonomic neuropathy has been evaluated in a group of diabetic patients in comparison with the sensitivity of a battery of the most commonly used cardiovascular autonomic tests (deep-breathing, lying-to-standing, Valsalva Manoeuvre, postural hypotension and hand grip). Spectral analysis of heart rate variability resulted in a very sensitive method for early detection of diabetic autonomic neuropathy, about one-fourth of diabetic patients with normal traditional cardiovascular autonomic tests had abnormal results at spectral analysis. Both sympathetic and vagal control of heart rate resulted alterated in diabetic autonomic neuropathy.

Adult↗
PubMed1990

Discontinuous distribution of IgG oligoclonal bands in cerebrospinal fluid from multiple sclerosis patients.

To test the effect of sampling on the detection of immunoglobulin (Ig) cerebrospinal fluid (CSF) abnormalities, we analyzed the first and last 1 ml fraction of 10 ml obtained during a single CSF removal from 27 multiple sclerosis (MS) patients and six patients with other neurological diseases. IgG index, hyperbolic function, and IgG synthesis rate decreased between the first and the last CSF aliquot. Discordant results were found in 4/27 (15%) MS patients. In 2/27 (7.5%) clinically definite MS patients, the number of CSF oligoclonal bands (OCB) decreased between the first and the last fraction. In one of the two patients, the three OCB visualized in the first fraction were not found in the last. We conclude that fractionated sampling may partially account for the absence of OCB in the CSF of some definite MS patients.

Adult↗