Arcuate fasciculus and speech in congenital bilateral perisylvian syndrome

Standard magnetic resonance imaging can diagnose congenital bilateral perisylvian polymicrogyria, but is limited in explaining the heterogeneous clinical spectrum of the related congenital bilateral perisylvian syndrome, characterized by pseudobulbar dysfunction, developmental delay, and epilepsy. We analyzed arcuate fasciculi using diffusion tensor imaging, a major language tract in the perisylvian region interconnecting the Broca and Wernicke areas, and at high risk of becoming developmentally affected in this condition. Six patients with congenital bilateral perisylvian syndrome underwent diffusion tensor imaging and were evaluated. The arcuate fasciculus was manually isolated, using tractography. The tract was identified in three patients who had developed speech, and whose values for various diffusion parameters were similar to those in age-matched controls (patients/controls means: fractional anisotropy, 0.50/0.52; apparent diffusion coefficient, 0.0022/0.0022 mm(2)/second; P = ns for both). However, in three patients with severe impairment and no speech development, the arcuate fasciculus could not be identified by fiber-tracking. In this small series, the absence of arcuate fasciculi on diffusion tensor imaging correlated with a more severe phenotype, which cannot be appreciated via structural magnetic resonance imaging alone.     

Molecular genetic studies in Indian patients with megalencephalic leukoencephalopathy

Mutations in the MLC1 gene cause megalencephalic leukoencephalopathy with subcortical cysts. We sought to identify mutations in the MLC1 gene, to evaluate the genotype-phenotype correlation, and to develop a strategy for diagnosing Indian patients with megalencephalic leukoencephalopathy. Forty patients were enrolled. We developed a rapid restriction fragment length polymorphism method to screen a common mutation, c.135_136insC. Rare and novel mutations were screened by conformation-sensitive gel electrophoresis, followed by sequencing. Three previously reported and two novel mutations were identified in 37 patients. The presence of the c.135_136insC mutation in 29 patients of the Agarwal community suggests a founder effect. The mutation c.959C>A was evident in four patients, and appears to be the second commonest mutation. Genotype could not predict phenotype. We recommend screening for the commonest mutation (c.135_136insC), followed by the next commonest mutation (c.959C>A), and then other rare mutations, using conformation-sensitive gel electrophoresis analysis or direct sequencing.     

Neuroprotection by rosiglitazone in transient focal cerebral ischemia might not be mediated by glutamate transporter-1

Glutamate transport represents a key mechanism for maintaining low level of glutamate in the extracellular milieu to restrict the excitotoxic action of glutamate released during ischemia/reperfusion (I/R) injury. Recently, it has been reported that glutamate transporter-1 (GLT-1) is a novel target for peroxisome proliferator-activated receptor-γ (PPARγ) agonist, which shows neuroprotection following oxygen glucose deprivation (OGD) in neuronal-astrocytic cocultures. Hence, the present study was undertaken to investigate the role of rosiglitazone in neuroprotection mediated by GLT-1 following focal cerebral I/R injury in rat. We found that rosiglitazone (2 mg/kg i.p) administered pre- or post-I/R injury significantly improved behavioral outcome and decreased cerebral infarct volume. However, no significant changes were observed in GLT-1 mRNA and protein expression in rosiglitazone-treated rats following 1 hr of ischemia/24 hr of reperfusion (1/24 hr I/R) injury. Interestingly, bioinformatics analysis also does not reveal any PPAR response element on the GLT-1/EAAT2 promoter region. Further rosiglitazone neither increased [(3) H]glutamate uptake in glia-enriched preparations nor caused any change in glutamine synthetase activity. On the other hand, there was a significant (P < 0.05) downregulation in tumor necrosis factor-α and interleukin-1β gene expression, which were more pronounced in the posttreatment group. The posttreatment with rosiglitazone also significantly reduced the increase in prostaglandin E2 level in the ischemic brain. Therefore, the present findings suggest that the neuroprotective effect of rosiglitazone does not seem to be mediated by modulation of GLT-1 protein expression/activity in a focal cerebral ischemia model. However, the results do provide increasing evidence that the neuroprotective effect may be mediated by its antiinflammatory action.     

Rapid assessment of hyperdiploidy in plasma cell disorders using a novel multi-parametric flow cytometry method

Trisomies of odd numbered chromosomes are seen in nearly half of patients with multiple myeloma (MM) and typically correlate with a hyperdiploid state and better overall survival (OS). We compared DNA ploidy of monoclonal plasma cells (as a surrogate for the presence of trisomies) assessed simultaneously by PCPRO (plasma cell proliferative index), a novel method that estimates DNA index by multi-parametric flow cytometry to fluorescence in situ hybridization (FISH) in 1703 patients with plasma cell disorders. The distribution of ploidy was hyperdiploid: 759 (45%), diploid 765 (45%), hypodiploid: 71 (4%), tetraploid/near-tetraploid: 108 (6%). FISH identified trisomies in 82% (621/756) of patients with hyperdiploidy by PCPRO and no trisomy by FISH was observed in 88% (730/834) of patients without hyperdiploidy. 95% (795/834) of patients without hyperdiploidy on PCPRO had one or less trisomy by FISH. Sensitivity and specificity of PCPRO for detecting hyperdiploidy was 86% (621/725) and 84% (730/865), respectively. Sensitivity increased to 94% (579/618) for patients with more than one trisomy. Newly diagnosed MM patients with hyperdiploidy on PCPRO (147/275) had better OS compared to nonhyperdiploid patients (median not reached vs 59 months, P = 0.008) and better progression free survival (median: 33 vs 23 months, P = 0.03). Within the hyperdiploidy group, patients with high-hyperdiploidy (DNA index: 1.19-1.50) versus those with low-hyperdiploidy (DNA index: 1.05-1.18) had superior OS (3 year OS of 88% vs 68% P = 0.03). Ploidy assessment by flow cytometry can provide rapid, valuable prognostic information and also reduces the number of copy number FISH probes required and hence the cost of FISH.     

Methotrexate preferentially affects Tc1 and Tc17 subset of CD8 T lymphocytes

Clinical Rheumatology - Rheumatoid arthritis is considered a T-lymphocyte-mediated disease. However, studies have focussed on CD4 T-lymphocytes, ignoring CD8 T-lymphocytes despite the latter being...     

Extensive cardiac cysticercosis–an interesting autopsy finding

Heart involvement in cysticercosis is rare, and most of the reports of cardiac cysticercosis have been in the form of autopsy studies. Generally, the heart involvement is part of a severe and generalized infection with the presence of only one or few cysts involving the myocardium. We report an interesting case of extensive cysticercosis of heart with innumerable cysts (around 100 in number) on the external surface of the heart on autopsy of a 30 year old female. Microscopic examination revealed wide spread involvement of myocardium. No such case of extensive cardiac cysticercosis has been reported in the literature so far. Apart from reporting a case study, we present interesting illustrations of such extensive involvement of heart in cysticercosis.