25 research outputs found
Increased Intrathecal Chemokine Receptor CCR2 Expression in Multiple Sclerosis
Expression of CCR2, CXCR3 and CCR4 on CD4+ T or CD8+ T cells in blood and cerebrospinal fluid (CSF) for multiple sclerosis (MS) was measured by 3-color flow cytometry, and compared to blood from healthy controls and CSF from patients with other inflammatory neurological diseases (INDs). CD4+CXCR3+/CD4+CCR4+ ratio (representing Th1/Th2 balance) was higher in both CSF and blood of MS patients than those of IND patients or healthy controls. Percentage of CCR2-positive T cells was significantly higher in CSF from MS patients. Increased CCR2 expression on T cells in CSF and Th1/Th2 imbalance may reflect the pathological processes involved in MS
Biological roles of anti-GM1 antibodies in patients with Guillain–Barré syndrome for nerve growth factor signaling
AbstractTo reveal the biological and pathological roles of anti-GM1 antibody in Guillain–Barré syndrome (GBS), we examined its effects on nerve growth factor (NGF) induced TrkA autophosphorylation (NGF-TrkA signaling) in PC12 cells, a sympathetic nerve cell line. The NGF-TrkA signaling is enhanced by exogenous GM1 ganglioside and this phenomenon is regarded as one of the functional aspects of GM1. The IgGs purified from patients' sera inhibited the NGF-TrkA signaling in GM1 pre-incubated PC12 cells. The degrees of inhibition by IgGs from patients paralleled their immunological reactivity to GM1. In addition, the IgGs also inhibited the neurite outgrowth of NGF-treated PC12 cells. Immunoglobulins in the rabbit sera, which were immunized by GM1, also caused a similar suppressive phenomenon. These results suggested that the anti-GM1 antibody could play roles in pathophysiology in anti-GM1 antibody positive GBS through interfering with the neurotrophic action of NGF and GM1 mediated signal modulation including NGF-TrkA signaling. It is suggested that the modulation of GM1 function is one important action of antibodies and could be one of the important mechanisms in GBS
Visual field defects of optic neuritis in neuromyelitis optica compared with multiple sclerosis
<p>Abstract</p> <p>Background</p> <p>Neuromyelitis optica (NMO) is an inflammatory demyelinating disease that predominantly affects the optic nerves and the spinal cord, and is possibly mediated by an immune mechanism distinct from that of multiple sclerosis (MS). Central scotoma is recognized as a characteristic visual field defect pattern of optic neuritis (ON), however, the differing pathogenic mechanisms of NMO and MS may result in different patterns of visual field defects for ON.</p> <p>Methods</p> <p>Medical records of 15 patients with NMO and 20 patients with MS having ON were retrospectively analyzed. A thorough systemic and neurological examination was performed for evaluating ON. The total number of relapses of ON and visual fields was investigated. Visual fields were obtained by Goldmann perimeter with each ON relapse.</p> <p>Results</p> <p>All MS patients experienced central scotoma, with 90% of them showing central scotoma with every ON relapse. However, 53% of NMO patients showed central scotoma with every ON relapse (p = 0.022), and the remaining 47% of patients experienced non-central scotoma (altitudinal, quadrant, three quadrant, hemianopia, and bitemporal hemianopia). Thirteen percent of NMO patients did not experience central scotoma during their disease course. Altitudinal hemianopia was the most frequent non-central scotoma pattern in NMO.</p> <p>Conclusions</p> <p>NMO patients showed higher incidence of non-central scotoma than MS, and altitudinal hemianopia may be characteristic of ON occurring in NMO. As altitudinal hemianopia is highly characteristic of ischemic optic neuropathy, we suggest that an ischemic mechanism mediated by anti-aquaporin-4 antibody may play a role in ON in NMO patients.</p
Interferon-β1b Increases Th2 Response in Neuromyelitis Optica
A Japanese randomized controlled study showed that Interferon â (IFN-â1b) therapy is clinically effective in decreasing the frequency of attacks in multiple sclerosis (MS), even in optico-spinal MS (OSMS). However, recent studies have shown that IFN-â (IFN-â1a/IFN-â1b) treatment was not effective in neuromyelitis optica (NMO) patients and that the diminished benefit of IFN-â treatment in NMO may be due to different immune responses to IFN-â. We determined longitudinally the expression of CCR5, CXCR3 and CCR4 on CD4+ T and CD8+ T cells in the blood from patients with NMO and MS treated with IFN-â1b. During a 12-month period of IFN-â1b therapy, the annualized relapse rate decreased in MS patients but not in NMO patients. There was no significant difference in the expression of the chemokine receptors between NMO and MS at baseline. The percentages of CD4+CCR5+ and CD4+CXCR3+ T cells, representative of the Th1 response, were decreased in both NMO and MS after treatment. The percentage of CD4+CCR4+ T cells, representative of the Th2 response, was decreased in MS, but those for NMO was significantly increased compared with the pretreatment levels. Our results indicate that IFN-â1b-induced up-modulation of the Th2 response in NMO patients may be the source of differences in the therapeutic response to IFN-â1b therapy. In the present study, Th2 predominance is involved in the pathogenesis of NMO
Postural abnormality as a risk marker for leg deep venous thrombosis in Parkinson's disease.
BACKGROUND: Pulmonary thromboembolism is a common cause of death in patients with autopsy-confirmed Parkinsonism. This study investigated the incidence of leg deep vein thrombosis in Parkinson's disease and relationships between deep vein thrombosis and clinical/laboratory findings, including postural abnormalities as assessed by photographic measurements. METHODS: This cross-sectional study assessed the presence of deep vein thrombosis using bilateral leg Doppler ultrasonography in 114 asymptomatic outpatients with Parkinson's disease. RESULTS: Deep vein thrombosis was detected in 23 patients (20%) with Parkinson's disease. Deep vein thrombosis was located in the distal portion in 18 patients and in the proximal portion in 5 patients. No significant differences in age, sex, body mass index, disease duration, Hoehn-Yahr stage, anti-Parkinson's drugs, or daily levodopa-equivalent dose were seen between deep vein thrombosis-positive and -negative groups. Univariate analysis for developing deep vein thrombosis in patients with Parkinson's disease identified the following markers: long-term wheelchair use, bent knee, bent spine, and D-dimer elevation. Bending angles were significantly greater in the deep vein thrombosis-positive group at the knee and spine than in the deep vein thrombosis-negative group. Half of Parkinson's disease patients with camptocormia had deep vein thrombosis. Among diabetes mellitus cases, long-term wheelchair use, bent knee over 15°, camptocormia, D-dimer elevation, the more risk markers were associated with a higher incidence of DVT. The presence of risk markers contributed to the development of deep vein thrombosis. On multivariate logistic regression analysis, a bent knee posture was strongly associated with an increased risk of deep vein thrombosis. CONCLUSION: Presence of leg deep vein thrombosis correlated with postural abnormalities in Parkinson's disease. We recommend non-invasive ultrasonographic screening for leg deep vein thrombosis in these high-risk patients with Parkinson's disease
Volcanic activity on Io and its influence on the dynamics of the Jovian magnetosphere observed by EXCEED/Hisaki in 2015
Abstract Jupiter’s moon Io, which orbits deep inside the magnetosphere, is the most geologically active object in the solar system. Kurdalagon Patera, a volcano on Io, erupted in 2015 and became a substantial source of Jovian magnetospheric plasma. Based on Earth-orbiting spacecraft observations, Io plasma torus (IPT) exhibited the peak intensity (nearly double) of ionic sulfur emissions roughly 2 month later, followed by a decay phase. This environmental change provides a unique opportunity to determine how the more heavily loaded magnetosphere behaves. Indeed, the extreme ultraviolet spectroscope for exospheric dynamics onboard the Earth-orbiting spacecraft Hisaki witnessed the whole interval via aurora and IPT observations. A simple-minded idea would be that the centrifugal force acting on fast co-rotating magnetic flux tubes loaded with heavier contents intensifies their outward transport. At the same time, there must be increased inward convection to conserve the magnetic flux. The latter could be accompanied by (1) increased inward velocity of field lines, (2) increased frequency of inward transport events, (3) increased inward flux carried per event, or (4) combinations of them. The Hisaki observations showed that the densities of major ions in the IPT increased and roughly doubled compared with pre-eruption values. The hot electron fraction, which sustains the EUV radiation from the IPT, gradually increased on a timescale of days. Pairs of intensified aurora and IPT brightening due to the enhanced supply of hot electrons from the mid-magnetosphere to the IPT upon aurora explosions observed during both quiet and active times, enabled the study of the mid-magnetosphere/IPT relationship. Hisaki observations under active Io conditions showed that: (1) the hot electron fraction in the torus gradually increased; (2) brightening pairs were more intense; (3) the energy supplied by the largest event maintained enhanced torus emission for less than a day; (4) the time delay of a torus brightening from a corresponding aurora intensification was roughly 11 h, that is, the same as during quiet times, suggesting that the inward convection speed of high-energy electrons does not change significantly. Graphical abstract