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1.
Reversible blockade of sodium channels by endogenous substances has been claimed to account for the fast exacerbations and relapses commonly seen in demyelinating autoimmune diseases. Evidence has been provided that in the cerebrospinal fluid of patients with multiple sclerosis or Guillain-Barré syndrome, a sodium-channel-blocking factor exists that has properties of local anesthetic agents. This factor could contribute to the nerve conduction block and paresis seen in these disorders. We describe here a previously unknown endogenous substance in human cerebrospinal fluid with distinct channel-blocking properties even at very low (0.00001 M) concentrations. The pentapeptide with the sequence Gln-Tyr-Asn-Ala-Asp exerted its blocking action by shifting the steady-state inactivation curve of the sodium channels to more-negative potentials, as most local anesthetics do. In the cerebrospinal fluid of healthy individuals, its concentration was about 3 microM, whereas in patients with multiple sclerosis and Guillain-Barré syndrome, it increased 300-1,400%. At these concentrations, the peptide's blocking efficacy was higher than that of 50 microM lidocaine. At a concentration of 10 microM, lidocaine is able to 'unmask' subclinical lesions in multiple sclerosis; thus, the endogenous pentapeptide may well contribute to the fast changes of symptoms. Furthermore, it may become valuable as a marker of disease activity.  相似文献   

2.
It is well known that misfolded peptides/proteins can play a role in processes of normal ageing and in the pathogenesis of many diseases including Alzheimer’s disease. Previously, we evaluated samples of cerebrospinal fluid from patients with Alzheimer’s disease and multiple sclerosis by means of thioflavin-T-based fluorescence. We observed attenuated effects of magnetite nanoparticles operated via anti-aggregation actions on peptides/proteins from patients with Alzheimer’s disease but not from those with multiple sclerosis when compared to age-related controls. In this study, we have evaluated the in vitro effects of anti-aggregation operating ferrofluid and phytoalexin spirobrassinin in the cerebrospinal fluid of patients with multiple sclerosis and Alzheimer’s disease. We have found significant differences in native fluorescence (λ excitation = 440 nm, λ emission = 485 nm) of samples among particular groups (young controls < multiple sclerosis, Alzheimer’s disease < old controls). Differences among groups were observed also in thioflavin-T-based fluorescence (young controls = multiple sclerosis < Alzheimer’s disease < old controls) and the most marked change from native to thioflavin-T-based fluorescence was found in young controls (28–40 years old people). Both ferrofluid and spirobrassinin evoked drops in thioflavin-T-based fluorescence; however, ferrofluid was more efficient in old controls (54–75 years old people) and spirobrassinin in multiple sclerosis patients, both compared to young controls. The results are discussed especially in relation to aggregated peptides/proteins and liposoluble fluorescent products of lipid peroxidation. Based on the significant effect of spirobrassinin in vitro, we suggest that spirobrassinin may be of therapeutic value in multiple sclerosis.  相似文献   

3.
Conduction along the optic nerve is often slowed in multiple sclerosis (MS). This is typically assessed by measuring the latency of the P100 component of the Visual Evoked Potential (VEP) using electroencephalography. The Visual Evoked Spread Spectrum Analysis (VESPA) method, which involves modulating the contrast of a continuous visual stimulus over time, can produce a visually evoked response analogous to the P100 but with a higher signal-to-noise ratio and potentially higher sensitivity to individual differences in comparison to the VEP. The main objective of the study was to conduct a preliminary investigation into the utility of the VESPA method for probing and monitoring visual dysfunction in multiple sclerosis. The latencies and amplitudes of the P100-like VESPA component were compared between healthy controls and multiple sclerosis patients, and multiple sclerosis subgroups. The P100-like VESPA component activations were examined at baseline and over a 3-year period. The study included 43 multiple sclerosis patients (23 relapsing-remitting MS, 20 secondary-progressive MS) and 42 healthy controls who completed the VESPA at baseline. The follow-up sessions were conducted 12 months after baseline with 24 MS patients (15 relapsing-remitting MS, 9 secondary-progressive MS) and 23 controls, and again at 24 months post-baseline with 19 MS patients (13 relapsing-remitting MS, 6 secondary-progressive MS) and 14 controls. The results showed P100-like VESPA latencies to be delayed in multiple sclerosis compared to healthy controls over the 24-month period. Secondary-progressive MS patients had most pronounced delay in P100-like VESPA latency relative to relapsing-remitting MS and controls. There were no longitudinal P100-like VESPA response differences. These findings suggest that the VESPA method is a reproducible electrophysiological method that may have potential utility in the assessment of visual dysfunction in multiple sclerosis.  相似文献   

4.
With the measles platelet aggregation test, a new technique recently developed for measuring virus antibody, 153 serum specimens from patients with multiple sclerosis and 164 controls were tested. With one of the three measles antigens used in the test a significantly higher positive rate (P<0·001) was obtained in the specimens from the patients with multiple sclerosis (40%) than in those from the controls (11%). The other two measles antigens also yielded slightly but not significantly higher positive rates in the patients with multiple sclerosis.  相似文献   

5.
Abstract— Myelin basic protein was isolated from the brains of 7 multiple sclerosis and 5 control patients. When acid extracts of the delipidated brains were chromatographed on carboxymethylcellulose at alkaline pH the elution profiles were the same for the two groups of patients. Component I, the most basic species of the protein, from 2 multiple sclerosis and one control brains was fragmented by limited pepsin digestion. Tryptic peptide maps were prepared from the three major products, fragment 1–38, 39–89 plus 45–89 and 90–170. The amino acid compositions of corresponding peptides were identical except for a 50:50 substitution of serine for glycine in tryptic peptide 44–49 from one (N.L.) of the 2 patients with multiple sclerosis. Peptide 44–49. isolated from intact component 1 from the other 6 multiple sclerosis and 5 control brains, did not show this substitution. In both multiple sclerosis and control basic proteins phosphorus was present only in fragment 90–170 of component 3 in the amount of 0.22 mol of phosphorus/mol of protein. These data suggest that there is no difference in either the amino acid sequence or in the modification of basic protein from control and multiple sclerosis patients. The amino acid substitution in patient N.L. represents the first example of a mutation in basic protein.  相似文献   

6.
Kirbey et al have reported that leukocyte function from patients with multiple sclerosis is not suppressed by PGE2, as are normal leukocytes. We examined the ability of PGE2 (0.01-0.5 microgram/ml) to suppress Phytohemagglutinin induced 3H-thymidine incorporation in peripheral blood lymphocytes from multiple sclerosis patients and normals. There was no difference in sensitivity between the two groups. There was also no difference in activity of the prostaglandin producing suppressor cell between the multiple sclerosis patients and controls.  相似文献   

7.
Objective To examine whether past high sun exposure is associated with a reduced risk of multiple sclerosis.Design Population based case-control study.Setting Tasmania, latitudes 41-3°S.Participants 136 cases with multiple sclerosis and 272 controls randomly drawn from the community and matched on sex and year of birth.Main outcome measure Multiple sclerosis defined by both clinical and magnetic resonance imaging criteria.Results Higher sun exposure when aged 6-15 years (average 2-3 hours or more a day in summer during weekends and holidays) was associated with a decreased risk of multiple sclerosis (adjusted odds ratio 0.31, 95% confidence interval 0.16 to 0.59). Higher exposure in winter seemed more important than higher exposure in summer. Greater actinic damage was also independently associated with a decreased risk of multiple sclerosis (0.32, 0.11 to 0.88 for grades 4-6 disease). A dose-response relation was observed between multiple sclerosis and decreasing sun exposure when aged 6-15 years and with actinic damage.Conclusion Higher sun exposure during childhood and early adolescence is associated with a reduced risk of multiple sclerosis. Insufficient ultraviolet radiation may therefore influence the development of multiple sclerosis.  相似文献   

8.
We have investigated the role of human endogenous retroviruses in multiple sclerosis by analyzing the DNA of patients and controls in 4 cohorts for associations between multiple sclerosis and polymorphisms near viral restriction genes or near endogenous retroviral loci with one or more intact or almost-intact genes. We found that SNPs in the gene TRIM5 were inversely correlated with disease. Conversely, SNPs around one retroviral locus, HERV-Fc1, showed a highly significant association with disease. The latter association was limited to a narrow region that contains no other known genes. We conclude that HERV-Fc1 and TRIM5 play a role in the etiology of multiple sclerosis. If these results are confirmed, they point to new modes of treatment for multiple sclerosis.  相似文献   

9.
Successful socialization requires the ability of understanding of others’ mental states. This ability called as mentalization (Theory of Mind) may become deficient and contribute to everyday life difficulties in multiple sclerosis. We aimed to explore the impact of brain pathology on mentalization performance in multiple sclerosis. Mentalization performance of 49 patients with multiple sclerosis was compared to 24 age- and gender matched healthy controls. T1- and T2-weighted three-dimensional brain MRI images were acquired at 3Tesla from patients with multiple sclerosis and 18 gender- and age matched healthy controls. We assessed overall brain cortical thickness in patients with multiple sclerosis and the scanned healthy controls, and measured the total and regional T1 and T2 white matter lesion volumes in patients with multiple sclerosis. Performances in tests of recognition of mental states and emotions from facial expressions and eye gazes correlated with both total T1-lesion load and regional T1-lesion load of association fiber tracts interconnecting cortical regions related to visual and emotion processing (genu and splenium of corpus callosum, right inferior longitudinal fasciculus, right inferior fronto-occipital fasciculus, uncinate fasciculus). Both of these tests showed correlations with specific cortical areas involved in emotion recognition from facial expressions (right and left fusiform face area, frontal eye filed), processing of emotions (right entorhinal cortex) and socially relevant information (left temporal pole). Thus, both disconnection mechanism due to white matter lesions and cortical thinning of specific brain areas may result in cognitive deficit in multiple sclerosis affecting emotion and mental state processing from facial expressions and contributing to everyday and social life difficulties of these patients.  相似文献   

10.
Platelet isolation techniques and platelet function were evaluated in 35 adult ponies. Platelet recovery from whole blood was consistent and the preparation of platelet rich plasma was facilitated by an enhanced erythrocyte sedimentation rate. All platelet samples aggregated in response to 10 microM ADP. However, concentrations of ADP as high as 100 microM did not elicit significant 14C-serotonin release. Collagen induced irreversible platelet aggregation and 14C-serotonin release in all samples. The threshold dose for collagen in most ponies was 1.5 micrograms. Arachidonic acid (500 microM) failed to induce irreversible platelet aggregation or 14C-serotonin release in any of the samples evaluated. Pony platelets were nonresponsive to epinephrine (5.5 microM).  相似文献   

11.
Susac syndrome, a rare but probably underdiagnosed combination of encephalopathy, hearing loss, and visual deficits due to branch retinal artery occlusion of unknown aetiology has to be considered as differential diagnosis in various conditions. Particularly, differentiation from multiple sclerosis is often challenging since both clinical presentation and diagnostic findings may overlap. Optical coherence tomography is a powerful and easy to perform diagnostic tool to analyse the morphological integrity of retinal structures and is increasingly established to depict characteristic patterns of retinal pathology in multiple sclerosis. Against this background we hypothesised that differential patterns of retinal pathology facilitate a reliable differentiation between Susac syndrome and multiple sclerosis. In this multicenter cross-sectional observational study optical coherence tomography was performed in nine patients with a definite diagnosis of Susac syndrome. Data were compared with age-, sex-, and disease duration-matched relapsing remitting multiple sclerosis patients with and without a history of optic neuritis, and with healthy controls. Using generalised estimating equation models, Susac patients showed a significant reduction in either or both retinal nerve fibre layer thickness and total macular volume in comparison to both healthy controls and relapsing remitting multiple sclerosis patients. However, in contrast to the multiple sclerosis patients this reduction was not distributed over the entire scanning area but showed a distinct sectorial loss especially in the macular measurements. We therefore conclude that patients with Susac syndrome show distinct abnormalities in optical coherence tomography in comparison to multiple sclerosis patients. These findings recommend optical coherence tomography as a promising tool for differentiating Susac syndrome from MS.  相似文献   

12.
Levels of free amino acids were determined in randomised, blinded samples of cerebrospinal fluid (CSF) from patients with relapsing-remitting or chronic progressive multiple sclerosis (MS), all in the active phase of disease. The levels were compared with amino acid amounts in patients with an acute polyradiculoneuropathy (Guillain-Barré syndrome (GBS)) and a control population of patients with no known neurological disease or deficit. The data did not indicate any significant changes in amino acid levels between MS subgroups. The only significant differences between MS patients and controls were a modest reduction in glutamate and a slight increase in taurine, but the changes were so small that the biological relevance is dubious. These results contrasted with the marked increases for many amino acids in CSF from patients with acute polyradiculoneuropathy compared with controls. The amino acid profile in cerebrospinal fluid (CSF) does not appear to provide evidence of differential pathology in multiple sclerosis (MS). The increase in hydrophobic amino acids and lysine in CSF from patients with acute polyradiculoneuropathy is consistent with transudation over the blood-CSF barrier following an infection. The increases in glutamine and alanine may reflect increased nitrogen removal from brain.  相似文献   

13.
The myelin basic protein gene (MBP) can confer the susceptibility to multiple sclerosis, because its protein product is the main protein component of myelin of the central nervous system and a potential autoimmune antigen in the disease. A possible association of multiple sclerosis with alleles and genotypes of a microsatellite repeat (TGGA)n, located to the 5' side from the first exon of MBP in ethnic Russians (126 patients with reliable multiple sclerosis and 142 healthy controls from Central Russia) was analyzed using the case-control method. Upon separation of the tetranucleotide repeat site amplification products in 1.5% agarose gel, one can see two distinct bands that can be analyzed as two allele groups (A and B). The distribution of allele A and B group frequencies as well as frequency of allele group B and genotype A/A reliably differs in multiple sclerosis patients and healthy controls. Alleles A and the A/A genotype are associated with the development of multiple sclerosis. We also analyzed the association of multiple sclerosis with combined bearing of alleles and genotypes A and B of MBP and groups of alleles of the DRB1 gene of the major histocompatibility complex that correspond to serospecificities DR1-DR18. The comparison of subgroups of multiple sclerosis patients and healthy individuals, formed on the basis of the DRB1 phenotype, has shown a reliable increase in the frequency of allele B in healthy individuals and the genotype A/A frequency in patients, only among DR4- and DR5-positive individuals. No reliable difference was found in the MBP allele and genotype distribution between multiple sclerosis patients and healthy individuals in combined groups of (DR4,DR5)-negative individuals, i.e., no carriers of any phenotype except DR4 and DR5 were revealed. Thus, MBP or some other nearby gene is involved in the multiple sclerosis development in Russians, predominantly (or exclusively) among DR4 and DR5 carriers. In this case, without stratification of analyzed individuals by the MBP alleles, multiple sclerosis is reliably associated only with DR2(15), but not of DR4 and DR5 alleles of DRB1. The results obtained are in favor of the genetic heterogeneity of multiple sclerosis, and suggest the possibility of epistatic interactions between the MBP and DRB1 genes.  相似文献   

14.
Kirbey et al have reported that leukocyte function from patients with multiple sclerosis is not suppressed by PGE2, as are normal leukocytes. We examined the ability of PGE2 (0.01–0.5 μg/ml) to suppress Phytohemagglutinin induced 3H-thymidine incorporation in peripheral blood lymphocytes from multiple sclerosis patients and normals. There was no difference in sensitivity between the two groups. There was also no difference in activity of the prostaglandin producing suppressor cell between the multiple sclerosis patients and controls.  相似文献   

15.
Urinary amines from 53 people who have multiple sclerosis and 58 controls have been separated and measured quantitatively by means of low-resolution ion-exchange procedure. Dependences on multiple sclerosis and on sex have been detected. The multiple-sclerosis-dependent pattern has been tested for diagnostic value by means of the weighted non-correlation index method.  相似文献   

16.
The binding of NADH and NAD+ to the human liver cytoplasmic, E1, and mitochondrial, E2, isozymes at pH 7.0 and 25 degrees C was studied by the NADH fluorescence enhancement technique, the sedimentation technique, and steady-state kinetics. The binding of radiolabeled [14C]NADH and [14C]NAD+ to the E1 isozyme when measured by the sedimentation technique yielded linear Scatchard plots with a dissociation constant of 17.6 microM for NADH and 21.4 microM for NAD+ and a stoichiometry of ca. two coenzyme molecules bound per enzyme tetramer. The dissociation constant, 19.2 microM, for NADH as competitive inhibitor was found from steady-state kinetics. With the mitochondrial E2 isozyme, the NADH fluorescence enhancement technique showed only one, high-affinity binding site (KD = 0.5 microM). When the sedimentation technique and radiolabeled coenzymes were used, the binding studies showed nonlinear Scatchard plots. A minimum of two binding sites with lower affinity was indicated for NADH (KD = 3-6 microM and KD = 25-30 microM) and also for NAD+ (KD = 5-7 microM and KD = 15-30 microM). A fourth binding site with the lowest affinity (KD = 184 microM for NADH and KD = 102 microM for NAD+) was observed from the steady-state kinetics. The dissociation constant for NAD+, determined by the competition with NADH via fluorescence titration, was found to be 116 microM. The number of binding sites found by the fluorescence titration (n = 1 for NADH) differs from that found by the sedimentation technique (n = 1.8-2.2 for NADH and n = 1.2-1.6 for NAD+).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

17.
Following the report of an increased mortality among patients with amyotrophic lateral sclerosis given high daily doses of branched-chain aminoacids, we assessed the plasma concentrations of large neutral aminoacids and glutamic acid and the large neutral aminoacid brain influx in 24 amyotrophic lateral sclerosis patients receiving placebo or branched-chain aminoacids ( -leucine 12 g, -isoleucine 6 g, -valine 6 g daily), in 15 untreated amyotrophic lateral sclerosis patients and in 15 healthy volunteers. The branched-chain aminoacid plasma concentrations increased three- to six-fold in the treated group compared to the patients receiving placebo or no treatment and to the healthy controls. Plasma glutamic acid concentrations in healthy volunteers were 51.59±7.53 nmol/ml while in the amyotrophic lateral sclerosis patients receiving no treatment, placebo or branched-chain aminoacids were 92.33±12.15 nmol/ml, 91.21±15.86 nmol/ml and 95.08±17.96 nmol/ml respectively. The glutamic acid concentration was significantly higher (P<0.01) in amyotrophic lateral sclerosis patients than in healthy individuals. Plasma phenylalanine and tyrosine were lower in the amyotrophic lateral sclerosis patients than in healthy controls, regardless of treatment, whereas tryptophan levels were not significantly different. The branched-chain aminoacid brain influx of the treated group was 110-140% of that measured in the patients receiving placebo and in the healthy controls. The aromatic aminoacid brain influx was lower in the treated group than in the placebo group or healthy controls. An impairment of brain large neutral aminoacid availability might possible contribute to enhancing the progression of symptoms in patients with amyotrophic lateral sclerosis.  相似文献   

18.
Cultures on anaerobic medium were made of the spinal fluids of 27 patients with multiple sclerosis and 13 controls after the method described recently by Ichelson. Where Ichelson found organisms resembling spirochetes in 78 per cent of patients with multiple sclerosis, we found some form of what appeared to be a living micro-organism in 18.5 per cent. The control fluids were all sterile. The work requires confirmation and amplification.  相似文献   

19.
Immunoglobulins M and G specific for meales, herpes simplex, and rubella viruses were assayed by the fluorescent antibody method in sera and cerebrospinal fluids (C.S.F.) obtained simultaneously from 30 patients with multiple sclerosis, 30 patients with other neurological diseases, and 30 “normal” control subjects. Sera of 11 out of 30 patients with multiple sclerosis had IgM which reacted specifically with measles virus-infected cells, compared with 2 out of 30 of the patients with other neurological diseases and none of the 30 normal controls. Virus-specific IgM was not found in C.S.F. by this method.The geometric mean titre of measles virus-specific IgG in serum was significantly higher in the multiple sclerosis group than in either control group, and while IgG specific for all three viruses was found in C.S.F., suggesting transfer across the blood-brain barrier, measles IgG predominated.  相似文献   

20.
Several lines of evidence suggest that mitochondrial genetic factors may influence susceptibility to multiple sclerosis. To explore this hypothesis further, we re-sequenced the mitochondrial genome (mtDNA) from 159 patients with multiple sclerosis and completed a haplogroup analysis including a further 835 patients and 1,506 controls. A trend towards over-representation of super-haplogroup U was the only evidence for association with mtDNA that we identified in these samples. In a parallel analysis of nuclear encoded mitochondrial genes, we also found a trend towards association with the complex I gene, NDUFS2. These results add to the evidence suggesting that variation in mtDNA and nuclear encoded mitochondrial genes may contribute to disease susceptibility in multiple sclerosis.  相似文献   

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