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81.
IL-6 induces regionally selective spinal cord injury in patients with the neuroinflammatory disorder transverse myelitis 总被引:3,自引:0,他引:3 下载免费PDF全文
Kaplin AI Deshpande DM Scott E Krishnan C Carmen JS Shats I Martinez T Drummond J Dike S Pletnikov M Keswani SC Moran TH Pardo CA Calabresi PA Kerr DA 《The Journal of clinical investigation》2005,115(10):2731-2741
Transverse myelitis (TM) is an immune-mediated spinal cord disorder associated with inflammation, demyelination, and axonal damage. We investigated the soluble immune derangements present in TM patients and found that IL-6 levels were selectively and dramatically elevated in the cerebrospinal fluid and directly correlated with markers of tissue injury and sustained clinical disability. IL-6 was necessary and sufficient to mediate cellular injury in spinal cord organotypic tissue culture sections through activation of the JAK/STAT pathway, resulting in increased activity of iNOS and poly(ADP-ribose) polymerase (PARP). Rats intrathecally infused with IL-6 developed progressive weakness and spinal cord inflammation, demyelination, and axonal damage, which were blocked by PARP inhibition. Addition of IL-6 to brain organotypic cultures or into the cerebral ventricles of adult rats did not activate the JAK/STAT pathway, which is potentially due to increased expression of soluble IL-6 receptor in the brain relative to the spinal cord that may antagonize IL-6 signaling in this context. The spatially distinct responses to IL-6 may underlie regional vulnerability of different parts of the CNS to inflammatory injury. The elucidation of this pathway identifies specific therapeutic targets in the management of CNS autoimmune conditions. 相似文献
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Mazur MA Gururangan S Bridge JA Cummings TJ Mukundan S Fuchs H Larrier N Halperin EC 《Pediatric blood & cancer》2005,45(6):850-856
The occurrence of primary extraosseous Ewing sarcoma (EES) of the central nervous system (CNS) has only rarely been reported in the literature. It is important to distinguish this entity from the more common central primitive neuroectodermal tumor (PNET) of brain, since the management of these tumors is different from that of EES. We present the clinical, radiologic, and pathologic features of two cases of EES occurring in the brain. The diagnosis was further confirmed by detection of a rearrangement of the FLI1 and/or EWS gene loci in tumors from both patients using fluorescent in situ hybridization (FISH). Although rare, the possibility of EES should be considered particularly when tumors that arise near the meningeal surface of the brain and have the pathologic appearance of a PNET. Demonstration of t(11;22)(q24;q12) by molecular analysis essentially confirms the diagnosis and enables the oncologist to choose appropriate therapy. 相似文献
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PURPOSE: To prospectively compare diffusion-tensor magnetic resonance (MR) imaging anisotropy measurements of white matter (WM) regions in early and late treatment groups of Krabbe disease patients treated with stem cell transplantation. MATERIALS AND METHODS: The study was approved by the Institutional Review Board and was compliant with Health Insurance Portability and Accountability Act; informed consent was obtained from the families of all patients. Patients with early-onset Krabbe disease (four girls and three boys) underwent diffusion-tensor MR imaging before and after stem cell transplantation. Fractional anisotropy (FA) values from serial studies were compared in patients who underwent transplantation at less than 1 month (early group, two girls and one boy) and those who underwent transplantation at 5-8 months (late group, two girls and two boys). FA values were measured in the genu and splenium of the corpus callosum, the frontal WM, and the internal capsule; were compared with those of five age-matched children in the comparison group (normal MR images and no proved neurologic disease); and were expressed as a ratio. Images obtained after transplantation were evaluated at approximately 1 (n = 7), 2 (n = 6), 3 (n = 1), and 4 (n = 1) years. RESULTS: Before transplantation, mean FA ratios in the early group for all four WM regions ranged between 97% and 117%. At 1 year, mean FA ratios at all locations were either 92% or 93%. At 2 years after transplantation, mean FA ratios were between 83% and 92%. In one patient imaged at 3 years, the mean FA ratio was 97%; in another patient imaged at 4 years, the mean FA ratio was 77%. Before transplantation, mean FA ratios in the late group ranged between 55% and 74%. Mean FA ratios were between 37% and 50% at 1 year after transplantation and between 36% and 39% at 2 years. CONCLUSION: All patients had decreases in FA ratios over time. The early group had higher initial FA ratios and lower subsequent decreases, which may indicate amelioration of the dysmyelinating process. 相似文献
85.
A 9-month-old boy presented with the complaints of loose motion, vomiting and difficulty in breathing. His scalp hairs were
thin, brittle, and sparse and were of differing lengths with twisted appearance. Hair shaft microscopy revealed alternate
light and dark segments and twisting of the hair shafts by 180 degrees along the axis. Serum copper levels were normal. The
audiological testing revealed bilateral sensorineural hearing loss. Child was diagnosed as a case of Bjornstad Syndrome. 相似文献
86.
We previously showed that acetaminophen administration to rats increases forebrain serotonin levels as a result of the inhibition of liver tryptophan-2,3-dioxygenase (TDO). In this study we determined whether aspirin alone and in combination with acetaminophen could further influence brain serotonin as well as norepinephrine levels and if so whether the status of the liver TDO activity would be altered. The results show that acetaminophen alone increases brain serotonin as well as norepinephrine levels with a concomitant inhibition of liver TDO activity. In contrast, aspirin did not alter the levels of these monoamines but increased serotonin turnover in the brain while acetaminophen decreased the turnover. When combined with acetaminophen, aspirin overrides the reduced serotonin turnover induced by acetaminophen. This report demonstrates the potential of these agents to alter neurotransmitter levels in the brain. 相似文献
87.
Jesudason MV Mukundan U Saaya R Vanitha K Lalitha MK 《Indian journal of medical microbiology》2003,21(2):127-128
Tuberculosis and more so the multi drug resistant variety has been thrust into the forefront as a serious and life threatening illness in recent years. The advent of AIDS contributes to this substantially, especially in the developed world where it had become practically non- existent. We reviewed our data over the past 20 years with a view to determine when drug resistance began to manifest in the strains. 相似文献
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Vasavada AR Goyal D Shastri L Singh R 《Journal of cataract and refractive surgery》2003,29(2):309-314
PURPOSE: To identify the types of corticocapsular adhesions by their preoperative clinical appearance and evaluate the difficulties they pose during cataract surgery. SETTING: Iladevi Cataract & IOL Research Center, Ahmedabad, India. METHODS: Seventy-six eyes with age-related senile cataract scheduled for phacoemulsification were identified as having corticocapsular adhesions. Preoperatively, the eyes were assessed at the slitlamp to determine the type of corticocapsular adhesions present. During surgery, the surgeon graded nucleus rotation after single-site cortical-cleaving hydrodissection as easy, difficult, or not possible. Additional multiquadrant-focal hydrodissection was performed. The surgeon's impressions of the presence of corticocapsular adhesions and visualization of the furry surface of the epinucleus were noted. RESULTS: Corticocapsular adhesions were confirmed in 86.84% of eyes. Equatorial corticocapsular adhesions alone or in combination were present in 72 eyes (94.74%) eyes, anterior corticocapsular adhesions in 40 (52.74%), and posterior corticocapsular adhesions in 42 (56.26%). Rotation of nucleus was not possible in 47.37% eyes, difficult in 39.47%, and easy in 13.16%. CONCLUSIONS: The surgeon should perform a thorough preoperative slitlamp evaluation in extreme gaze with a fully dilated pupil. Equatorial corticocapsular adhesions, which were present in most eyes, made nucleus rotation difficult. Additional multiquadrant and focal cortical-cleaving hydrodissection helped separate the adhesions and achieve successful rotation. 相似文献