Severity of white matter microstructural damage in a Brazilian relapsing-remitting multiple sclerosis cohort: A possible window to optimize treatment.

BACKGROUND: Multiple sclerosis (MS) is an important cause of acquired neurological disability in young adults, characterized by multicentric inflammation, demyelination, and axonal damage. OBJECTIVE: The objective is to investigate white matter (WM) damage progression in a Brazilian MS patient cohort, using diffusion tensor imaging (DTI) post-processed by tract-based spatial statistics (TBSS). METHODS: DTI scans were acquired from 76 MS patients and 37 sex-and-age matched controls. Patients were divided into three groups based on disease duration. DTI was performed along 30 non-collinear directions by using a 1.5T imager. For TBSS analysis, the WM skeleton was created, and a 5000 permutation-based inference with a threshold of p < .05 was used, to enable the identification of abnormalities in fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD). RESULTS: Decreased FA and increased RD, MD, and AD were seen in patients compared to controls and a decreased FA and increased MD and RD were seen, predominantly after the first 5 years of disease, when compared between groups. CONCLUSION: Progressive WM deterioration is seen over time with a more prominent pattern after 5 years of disease onset, providing evidence that the early years might be a window to optimize treatment and prevent disability.

Synaptic proteasome is inhibited in Alzheimer's disease models and associates with memory impairment in mice.

The proteasome plays key roles in synaptic plasticity and memory by regulating protein turnover, quality control, and elimination of oxidized/misfolded proteins. Here, we investigate proteasome function and localization at synapses in Alzheimer's disease (AD) post-mortem brain tissue and in experimental models. We found a marked increase in ubiquitinylated proteins in post-mortem AD hippocampi compared to controls. Using several experimental models, we show that amyloid-ß oligomers (AßOs) inhibit synaptic proteasome activity and trigger a reduction in synaptic proteasome content. We further show proteasome inhibition specifically in hippocampal synaptic fractions derived from APPswePS1ΔE9 mice. Reduced synaptic proteasome activity instigated by AßOs is corrected by treatment with rolipram, a phosphodiesterase-4 inhibitor, in mice. Results further show that dynein inhibition blocks AßO-induced reduction in dendritic proteasome content in hippocampal neurons. Finally, proteasome inhibition induces AD-like pathological features, including reactive oxygen species and dendritic spine loss in hippocampal neurons, inhibition of hippocampal mRNA translation, and memory impairment in mice. Results suggest that proteasome inhibition may contribute to synaptic and memory deficits in AD.

Influence of natalizumab on resting-state connectivity in patients with multiple sclerosis.

Background: Changes in brain connectivity occur in patients with multiple sclerosis (MS), even in patients under disease-modifying therapies. Using magnetic resonance imaging (MRI) to asses patients treated with disease-modifying therapies, such as natalizumab, can elucidate the mechanisms involved in clinical deterioration in MS. Objectives: To evaluate differences in resting-state functional connectivity among MS patients treated with natalizumab, MS patients not treated with natalizumab, and controls. Design: Single-center retrospective cross-sectional study. Methods: Twenty-three MS patients being treated with natalizumab were retrospectively compared with 23 MS patients who were naïve for natalizumab, and were using first-line medications (interferon-ß and/or glatiramer acetate), and 17 gender- and age-matched control subjects. The MS patient groups were also matched for time since diagnosis and hyperintense lesion volume on FLAIR. All participants underwent brain MRI using a 3 Tesla scanner. Independent component analysis and dual regression were used to identify resting-state functional connectivity using the FMRIB Software Library. Results: In comparison to controls, the MS patients treated with natalizumab presented decreased connectivity in the left orbitofrontal cortex, in the anterior cingulate and orbitofrontal cortex network. The patients not treated with natalizumab presented increased connectivity in the secondary visual, sensorimotor, and ventral attention networks in comparison to controls.Compared to patients treated with natalizumab, the patients not using natalizumab presented increased connectivity in the left Heschl's gyrus and in the right superior frontal gyrus in the ventral attention network. Conclusion: Differences in brain connectivity between MS patients not treated with natalizumab, healthy controls, and patients treated with natalizumab may be secondary to suboptimal neuronal compensation due to prior less efficient treatments, or due to a compensation in response to maladaptive plasticity.

Higher frequency of Human herpesvirus-6 (HHV-6) viral DNA simultaneously with low frequency of Epstein-Barr virus (EBV) viral DNA in a cohort of multiple sclerosis patients from Rio de Janeiro, Brazil.

Multiple sclerosis (MS) is a chronic neuroinflammatory and neurodegenerative disease of the central nervous system (CNS). The etiology of MS is not well understood, but it's likely one of the genetic and environmental factors. Approximately 85% of patients have relapsing-remitting MS (RRMS), while 10-15% have primary progressive MS (PPMS). Epstein-Barr virus (EBV) and Human herpesvirus 6 (HHV-6), members of the human Herpesviridae family, are strong candidates for representing the macroenvironmental factors associated with MS) pathogenesis. Antigenic mimicry of EBV involving B-cells has been implicate in MS risk factors and concomitance of EBV and HHV-6 latent infection has been associated to inflammatory MS cascade. To verify the possible role of EBV and HHV-6 as triggering or aggravating factors in RRMS and PPMS, we compare their frequency in blood samples collected from 166 MS patients. The presence of herpes DNA was searched by real-time PCR (qPCR). The frequency of EBV and HHV-6 in MS patients were 1.8% (3/166) and 8.9% (14/166), respectively. Among the positive patients, 100% (3/3) EBV and 85.8% (12/14) HHV-6 are RRMS and 14.4% (2/14) HHV-6 are PPMS. Detection of EBV was 1.2% (2/166) and HHV-6 was 0.6% (1/166) in blood donors. About clinical phenotype of these patients, incomplete multifocal myelitis, and optic neuritis were the main CNS manifestations. These are the first data about concomitant infection of these viruses in MS patients from Brazil. Up to date, our findings confirm a higher prevalence in female with MS and a high frequency of EBV and HHV-6 in RRMS patients.

SARS-CoV-2 Spike protein induces TLR4-mediated long-term cognitive dysfunction recapitulating post-COVID-19 syndrome in mice.

Cognitive dysfunction is often reported in patients with post-coronavirus disease 2019 (COVID-19) syndrome, but its underlying mechanisms are not completely understood. Evidence suggests that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Spike protein or its fragments are released from cells during infection, reaching different tissues, including the CNS, irrespective of the presence of the viral RNA. Here, we demonstrate that brain infusion of Spike protein in mice has a late impact on cognitive function, recapitulating post-COVID-19 syndrome. We also show that neuroinflammation and hippocampal microgliosis mediate Spike-induced memory dysfunction via complement-dependent engulfment of synapses. Genetic or pharmacological blockage of Toll-like receptor 4 (TLR4) signaling protects animals against synapse elimination and memory dysfunction induced by Spike brain infusion. Accordingly, in a cohort of 86 patients who recovered from mild COVID-19, the genotype GG TLR4-2604G>A (rs10759931) is associated with poor cognitive outcome. These results identify TLR4 as a key target to investigate the long-term cognitive dysfunction after COVID-19 infection in humans and rodents.

Assessing the antiproliferative effect of biogenic silver chloride nanoparticles on glioblastoma cell lines by quantitative image-based analysis.

Glioblastoma is the most life-threatening tumour of the central nervous system. Temozolomide (TMZ) is the first-choice oral drug for the treatment of glioblastoma, although it shows low efficacy. Silver nanoparticles (AgNPs) have been shown to exhibit biocidal activity in a variety of microorganisms, including some pathogenic microorganisms. Herein, the antiproliferative effect of AgCl-NPs on glioblastoma cell lines (GBM02 and GBM11) and on astrocytes was evaluated through automated quantitative image-based analysis (HCA) of the cells. The cells were treated with 0.1-5.0 µg/ml AgCl-NPs or with 9.7-48.5 µg/ml TMZ. Cells that received combined treatment were also analysed. At a maximum tested concentration of AgCl-NPs, GBM02 and GBM11, the growth decreased by 93% and 40%, respectively, following 72 h of treatment. TMZ treatment decreased the proliferation of GBM02 and GBM11 cells by 58% and 34%, respectively. Combinations of AgCl-NPs and TMZ showed intermediate antiproliferative effects; the lowest concentrations caused an inhibition similar to that obtained with TMZ, and the highest concentrations caused inhibition similar to that obtained with AgCl-NPs alone. No significant changes in astrocyte proliferation were observed. The authors' findings showed that HCA is a fast and reliable approach that can be used to evaluate the antiproliferative effect of the nanoparticles at the single-cell level and that AgCl-NPs are promising agents for glioblastoma treatment.

Association between high titers of glutamic acid decarboxylase antibody and epilepsy in patients with type 1 diabetes mellitus: A cross-sectional study.

PURPOSE: Individuals with type 1 diabetes mellitus (T1D) are at higher risk of epilepsy. T1D is a progressive immune-mediated disease and the etiology of epilepsy remains unknown in most. Glutamic acid decarboxylase (GAD) catalyzes GABA formation. GABA-secreting neurons and pancreatic beta cells are the major cells expressing GAD. METHODS: Cross-sectional study. Patients with T1D from a multiethnic population underwent GADA measurement to investigate possible association between T1D and epilepsy of unknown etiology. RESULTS: T1D patients were analyzed (n = 375). Overall frequency of epilepsy was 5.9% (n = 22). Frequency of epilepsy of unknown etiology was 3.2% (n = 12). Of these, 8 (2.1%) had idiopathic generalized epilepsy (IGE) and 4 (1.1%) MRI-negative temporal lobe epilepsy (TLE). Patients with T1D and epilepsy of unknown etiology did not show differences in GADA frequency (83.3% vs 50%; p = 0.076); however, their titers were higher (106.9 ±â€¯136.5 IU/mL; median 7; IQR 1.65-256 vs 10.2 ±â€¯14.5 IU/ml; median 4.3; IQR 1.9-8.9; p = 0.019) compared to patients without epilepsy. Moreover, epilepsy of unknown etiology was associated with GADA titers ≥ 100 UI/mL [odds ratio (OR) 4.42, 95% CI 2.36-8.66]. CONCLUSION: Epilepsy frequency was elevated in patients with T1D and multiethnic background. Presence of epilepsy of unknown etiology was associated with high titers of GADA in this population with long-standing T1D, which has different ethnic and genetic background compared to previous studies. Further prospective studies are required to identify if GADA presence or its persistence are directly responsible for epilepsy in individuals with T1D.

Zika virus replicates in adult human brain tissue and impairs synapses and memory in mice.

Neurological complications affecting the central nervous system have been reported in adult patients infected by Zika virus (ZIKV) but the underlying mechanisms remain unknown. Here, we report that ZIKV replicates in human and mouse adult brain tissue, targeting mature neurons. ZIKV preferentially targets memory-related brain regions, inhibits hippocampal long-term potentiation and induces memory impairment in adult mice. TNF-α upregulation, microgliosis and upregulation of complement system proteins, C1q and C3, are induced by ZIKV infection. Microglia are found to engulf hippocampal presynaptic terminals during acute infection. Neutralization of TNF-α signaling, blockage of microglial activation or of C1q/C3 prevent synapse and memory impairment in ZIKV-infected mice. Results suggest that ZIKV induces synapse and memory dysfunction via aberrant activation of TNF-α, microglia and complement. Our findings establish a mechanism by which ZIKV affects the adult brain, and point to the need of evaluating cognitive deficits as a potential comorbidity in ZIKV-infected adults.

Migraine in 746 patients with multiple sclerosis.

Migraine adds to the burden of patients suffering from multiple sclerosis (MS). The ID-migraine is a useful tool for screening migraine, and the Migraine Disability Assessment questionnaire can evaluate disease burden. The aim of the present study was to assess the presence and burden of migraine in patients with MS. METHODS Patients diagnosed with MS attending specialized MS units were invited to answer an online survey if they also experienced headache. RESULTS The study included 746 complete responses from patients with MS and headache. There were 625 women and 121 men, and 69% of all the patients were aged between 20 and 40 years. Migraine was identified in 404 patients (54.1%) and a moderate-to-high burden of disease was observed in 68.3% of the patients. CONCLUSION Migraine is a frequent and disabling type of primary headache reported by patients with MS.

Migraine in 746 patients with multiple sclerosis / Enxaqueca em 746 pacientes com esclerose múltipla

ABSTRACT Migraine adds to the burden of patients suffering from multiple sclerosis (MS). The ID-migraine is a useful tool for screening migraine, and the Migraine Disability Assessment questionnaire can evaluate disease burden. The aim of the present study was to assess the presence and burden of migraine in patients with MS. Methods: Patients diagnosed with MS attending specialized MS units were invited to answer an online survey if they also experienced headache. Results: The study included 746 complete responses from patients with MS and headache. There were 625 women and 121 men, and 69% of all the patients were aged between 20 and 40 years. Migraine was identified in 404 patients (54.1%) and a moderate-to-high burden of disease was observed in 68.3% of the patients. Conclusion: Migraine is a frequent and disabling type of primary headache reported by patients with MS.

RESUMO Enxaqueca piora o sofrimento do paciente que tem esclerose múltipla (EM). ID-migraine é uma ferramenta útil para seleção de pacientes com enxaqueca e Migraine Disability Assessment (MIDAS) é um questionário que avalia o impacto da doença. O objetivo do presente estudo foi avaliar a presença e impacto de enxaqueca em pacientes com EM. Métodos: Pacientes diagnosticados com EM e tratados em clínicas especializadas foram convidados a responder um questionário online se também apresentassem cefaleia. Resultados: O estudo incluiu 746 participantes com cefaleia e EM que preencheram completamente as respostas. Foram 625 mulheres e 121 homens, sendo 69% dos pacientes com idade entre 20 e 40 anos. Enxaqueca foi identificada em 404 pacientes (54,1%) e moderado a grave impacto da doença foi observado em 68,3% dos casos. Conclusão: Enxaqueca é uma cefaleia primária frequente e incapacitante relatada por pacientes com EM.

Frequency of Pseudotumoral Central Nervous System Lesions in an Oncology Center.

BACKGROUND: Brain tumors are frequent in clinical practice and associated with high morbidity and mortality. However, many diseases can present as tumefactive lesions and mimic neoplastic lesions. We aimed to determine the frequency of pseudotumoral central nervous system lesions referred to an oncology center and the frequency of the tumor mimickers. METHODS: This was a retrospective study at the National Institute of Cancer, Rio de Janeiro, Brazil. Medical charts of patients admitted to the Neurosurgery and Pediatrics services from 2007 to 2011 were reviewed. Clinical and radiologic features of cases initially diagnosed with primary central nervous system tumors but received a final diagnosis of pseudotumoral disease were recorded. RESULTS: Among 891 patients referred as primary brain tumors, 38 cases had pseudotumoral lesions (4.3%). Most were adults (63%), with mean age of 29.4 years, and women (60.5%). Most frequent symptoms were headache (28.9%), motor signs (23.7%), and seizures (15.8%). Mean time from initial symptoms to diagnosis was 12.2 months. Lesions were single in 84.2% of patients, had contrast enhancement in 45.6%, and surrounding edema in 17.4%. Twenty patients (52,6%) underwent biopsy. Systemic autoimmune diseases were the most frequent etiologies (28.9%), followed by idiopathic inflammatory demyelinating diseases, infections, and vascular abnormalities (15.8% each). Good outcome with no major deficits was observed in 60.5% cases. CONCLUSIONS: The frequency of pseudotumoral lesions in an oncology reference center was low. Young women were most affected, and lesions were associated more frequently with systemic autoimmune diseases. Prompt recognition is important to avoid unnecessary treatment, because most patients had a good outcome.

Different interleukin-17-secreting Toll-like receptor+ T-cell subsets are associated with disease activity in multiple sclerosis.

Signalling through Toll-like receptors (TLRs) may play a role in the pathogenesis of autoimmune diseases, such as multiple sclerosis (MS). In the present study, the expression of TLR-2, -4 and -9 was significantly higher on CD4+ and CD8+ T-cells from MS patients compared to healthy individuals. Following in-vitro activation, the proportion of interleukin (IL)-17+ and IL-6+ CD4+ and CD8+ T-cells was higher in the patients. In addition, the proportion of IFN-γ-secreting TLR+ CD8+ T-cells was increased in MS patients. Among different IL-17+ T-cell phenotypes, the proportion of IL-17+ TLR+ CD4+ and CD8+ T-cells producing IFN-γ or IL-6 were positively associated with the number of active brain lesions and neurological disabilities. Interestingly, activation of purified CD4+ and CD8+ T-cells with ligands for TLR-2 (Pam3Csk4), TLR-4 [lipopolysaccharide (LPS)] and TLR-9 [oligodeoxynucleotide (ODN)] directly induced cytokine production in MS patients. Among the pathogen-associated molecular patterns (PAMPs), Pam3Csk4 was more potent than other TLR ligands in inducing the production of all proinflammatory cytokines. Furthermore, IL-6, IFN-γ, IL-17 and granulocyte-macrophage colony-stimulating factor (GM-CSF) levels produced by Pam3Csk4-activated CD4+ cells were directly associated with disease activity. A similar correlation was observed with regard to IL-17 levels released by Pam3Csk4-stimulated CD8+ T-cells and clinical parameters. In conclusion, our data suggest that the expansion of different T helper type 17 (Th17) phenotypes expressing TLR-2, -4 and -9 is associated with MS disease activity, and reveals a preferential ability of TLR-2 ligand in directly inducing the production of cytokines related to brains lesions and neurological disabilities.

Astrocyte Transforming Growth Factor Beta 1 Protects Synapses against Aß Oligomers in Alzheimer's Disease Model.

Alzheimer's disease (AD) is characterized by progressive cognitive decline, increasingly attributed to neuronal dysfunction induced by amyloid-ß oligomers (AßOs). Although the impact of AßOs on neurons has been extensively studied, only recently have the possible effects of AßOs on astrocytes begun to be investigated. Given the key roles of astrocytes in synapse formation, plasticity, and function, we sought to investigate the impact of AßOs on astrocytes, and to determine whether this impact is related to the deleterious actions of AßOs on synapses. We found that AßOs interact with astrocytes, cause astrocyte activation and trigger abnormal generation of reactive oxygen species, which is accompanied by impairment of astrocyte neuroprotective potential in vitro We further show that both murine and human astrocyte conditioned media (CM) increase synapse density, reduce AßOs binding, and prevent AßO-induced synapse loss in cultured hippocampal neurons. Both a neutralizing anti-transforming growth factor-ß1 (TGF-ß1) antibody and siRNA-mediated knockdown of TGF-ß1, previously identified as an important synaptogenic factor secreted by astrocytes, abrogated the protective action of astrocyte CM against AßO-induced synapse loss. Notably, TGF-ß1 prevented hippocampal dendritic spine loss and memory impairment in mice that received an intracerebroventricular infusion of AßOs. Results suggest that astrocyte-derived TGF-ß1 is part of an endogenous mechanism that protects synapses against AßOs. By demonstrating that AßOs decrease astrocyte ability to protect synapses, our results unravel a new mechanism underlying the synaptotoxic action of AßOs in AD.SIGNIFICANCE STATEMENT Alzheimer's disease is characterized by progressive cognitive decline, mainly attributed to synaptotoxicity of the amyloid-ß oligomers (AßOs). Here, we investigated the impact of AßOs in astrocytes, a less known subject. We show that astrocytes prevent synapse loss induced by AßOs, via production of transforming growth factor-ß1 (TGF-ß1). We found that AßOs trigger morphological and functional alterations in astrocytes, and impair their neuroprotective potential. Notably, TGF-ß1 reduced hippocampal dendritic spine loss and memory impairment in mice that received intracerebroventricular infusions of AßOs. Our results describe a new mechanism underlying the toxicity of AßOs and indicate novel therapeutic targets for Alzheimer's disease, mainly focused on TGF-ß1 and astrocytes.

Amyloid-ß oligomers transiently inhibit AMP-activated kinase and cause metabolic defects in hippocampal neurons.

AMP-activated kinase (AMPK) is a key player in energy sensing and metabolic reprogramming under cellular energy restriction. Several studies have linked impaired AMPK function to peripheral metabolic diseases such as diabetes. However, the impact of neurological disorders, such as Alzheimer disease (AD), on AMPK function and downstream effects of altered AMPK activity on neuronal metabolism have been investigated only recently. Here, we report the impact of Aß oligomers (AßOs), synaptotoxins that accumulate in AD brains, on neuronal AMPK activity. Short-term exposure of cultured rat hippocampal neurons or ex vivo human cortical slices to AßOs transiently decreased intracellular ATP levels and AMPK activity, as evaluated by its phosphorylation at threonine residue 172 (AMPK-Thr(P)172). The AßO-dependent reduction in AMPK-Thr(P)172 levels was mediated by glutamate receptors of the N-methyl-d-aspartate (NMDA) subtype and resulted in removal of glucose transporters (GLUTs) from the surfaces of dendritic processes in hippocampal neurons. Importantly, insulin prevented the AßO-induced inhibition of AMPK. Our results establish a novel toxic impact of AßOs on neuronal metabolism and suggest that AßO-induced, NMDA receptor-mediated AMPK inhibition may play a key role in early brain metabolic defects in AD.

Interaction of amyloid-ß (Aß) oligomers with neurexin 2α and neuroligin 1 mediates synapse damage and memory loss in mice.

Brain accumulation of the amyloid-ß protein (Aß) and synapse loss are neuropathological hallmarks of Alzheimer disease (AD). Aß oligomers (AßOs) are synaptotoxins that build up in the brains of patients and are thought to contribute to memory impairment in AD. Thus, identification of novel synaptic components that are targeted by AßOs may contribute to the elucidation of disease-relevant mechanisms. Trans-synaptic interactions between neurexins (Nrxs) and neuroligins (NLs) are essential for synapse structure, stability, and function, and reduced NL levels have been associated recently with AD. Here we investigated whether the interaction of AßOs with Nrxs or NLs mediates synapse damage and cognitive impairment in AD models. We found that AßOs interact with different isoforms of Nrx and NL, including Nrx2α and NL1. Anti-Nrx2α and anti-NL1 antibodies reduced AßO binding to hippocampal neurons and prevented AßO-induced neuronal oxidative stress and synapse loss. Anti-Nrx2α and anti-NL1 antibodies further blocked memory impairment induced by AßOs in mice. The results indicate that Nrx2α and NL1 are targets of AßOs and that prevention of this interaction reduces the deleterious impact of AßOs on synapses and cognition. Identification of Nrx2α and NL1 as synaptic components that interact with AßOs may pave the way for development of novel approaches aimed at halting synapse failure and cognitive loss in AD.

Interleukin-17- and interleukin-22-secreting myelin-specific CD4(+) T cells resistant to corticoids are related with active brain lesions in multiple sclerosis patients.

Multiple sclerosis (MS) is thought to be an autoimmune disorder. It is believed that immunological events in the early stages have great impact on the disease course. Therefore, we aimed to evaluate the cytokine profile of myelin basic protein (MBP)-specific T cells from MS patients in the early phase of the disease and correlate it to clinical parameters, as well as to the effect of in vitro corticoid treatment. Peripheral T cells from MS patients were stimulated with MBP with our without hydrocortisone for 5 days. The cytokines level were determined by ELISA. The number of active brain lesions was determined by MRI scans, and the neurological disabilities were assessed by Expanded Disability Status Scale scores. Our results demonstrated that MS-derived T cells responded to MBP by producing high levels of T helper type 1 (Th1) and Th17 cytokines. Although the production of interleukin-6 (IL-6), granulocyte-macrophage colony-stimulating factor, IL-17 and IL-22 was less sensitive to hydrocortisone inhibition, only IL-17 and IL-22 levels correlated with active brain lesions. The ability of hydrocortisone to inhibit IL-17 and IL-22 production by MBP-specific CD4(+) T cells was inversely related to the number of active brain lesions. Finally, the production of both cytokines was significantly higher in cell cultures from Afrodescendant patients and it was less sensitive to hydrocortisone inhibition. In summary, our data suggest that IL-17- and IL-22-secreting CD4(+) T cells resistant to corticoids are associated with radiological activity of the MS in early stages of the disease, mainly among Afrodescendant patients who, normally, have worse prognosis.

Genetic association study of the HLA class II alleles DRB1, DQA1, and DQB1 in patients with pharmacoresistant temporal lobe epilepsy associated with mesial hippocampal sclerosis.

PURPOSE: Temporal lobe epilepsy (TLE) is the most common variety of focal epilepsy among adults. The neuroinflammatory mechanisms of epilepsies may be involved in the genesis of seizures and refractory epilepsies, particularly in the case of progressive syndromes such as TLE associated with mesial hippocampal sclerosis (TLE-HS). The goal of the present study is investigate the genetic profile of susceptibility of individuals with TLE-HS by analyzing the possible association of TLE-HS with human leukocyte antigen (HLA) DRB1, DQA1 and DQB1 alleles. METHODS: Peripheral blood samples were collected from 42 individuals with pharmacoresistant TLE-HS and 89 healthy controls. The typing of the HLA class II alleles from DRB1, DQB1, and DQA1 loci were analyzed using sequence-specific primer-polymerase chain reaction (SSP-PCR) and identified through sequencing. Statistical analysis of relative allele frequencies was performed using an Excel spreadsheet; p-value, relative risk (RR), and odds ratio (OR) were calculated using the software Epi Info 6.0. p-values <0.05 following Bonferroni's method correction were considered statistically significant. RESULTS: HLA-DRB1*13:02 was the only allele with a statistically significant difference (p=0.01) in frequency between patients and controls. However, the significance was lost following Bonferroni's method correction (p=0.44). The remainder of the alleles in the HLA-DRB1, HLA-DQB1 and HLA-DQA1 regions did not exhibit any significant association. CONCLUSION: The allele HLA DRB1*13:02 has exhibited a tendency to behave as a susceptibility factor for TLE-HS.

The CIITA genetic polymorphism rs4774*C in combination with the HLA-DRB1*15:01 allele as a putative susceptibility factor to multiple sclerosis in Brazilian females.

The objective of this study was to investigate the association between the HLA alleles at the DQA1, DQB1 and DRB1 loci, the CIITA genetic polymorphisms -168A/G and +1614G/C, and susceptibility to multiple sclerosis (MS) in a sample from Rio de Janeiro State, Brazil. Furthermore, we wished to determine whether any of these associations might be more significant in women compared with men. DNA samples from 52 relapsing-remitting MS (RRMS) patients and 126 healthy controls matched for sex and age were analyzed. We identified a significant HLA-DRB1*15:01-MS association that was female-specific (Odds Ratio (OR) = 4.78; p = 0.001). Furthermore, we observed that the +1614G/C mutation in combination with the HLA-DRB1*15:01 allele increased susceptibility to MS in females (OR = 4.55; p = 0.01). Together, these findings highlight the polygenic nature of MS.

The CIITA genetic polymorphism rs4774*C in combination with the HLA-DRB1*15:01 allele as a putative susceptibility factor to multiple sclerosis in Brazilian females / O polimorfismo rs4774*C no gene CIITA em conjunção com o alelo HLA-DRB1*15:01 é um possível fator de susceptibilidade a esclerose múltipla em mulheres brasileiras

The objective of this study was to investigate the association between the HLA alleles at the DQA1, DQB1 and DRB1 loci, the CIITA genetic polymorphisms -168A/G and +1614G/C, and susceptibility to multiple sclerosis (MS) in a sample from Rio de Janeiro State, Brazil. Furthermore, we wished to determine whether any of these associations might be more significant in women compared with men. DNA samples from 52 relapsing-remitting MS (RRMS) patients and 126 healthy controls matched for sex and age were analyzed. We identified a significant HLA-DRB1*15:01-MS association that was female-specific (Odds Ratio (OR) = 4.78; p = 0.001). Furthermore, we observed that the +1614G/C mutation in combination with the HLA-DRB1*15:01 allele increased susceptibility to MS in females (OR = 4.55; p = 0.01). Together, these findings highlight the polygenic nature of MS.

O objetivo deste estudo foi investigar a associação entre alelos HLA, loci DQA1, DQB1 e DRB1, polimorfismos -168A/G e +1614G/C no gene CIITA, e suscetibilidade à esclerose múltipla (EM) em uma amostra de Rio de Janeiro, Brasil. Além disso, buscou-se determinar se alguma dessas associações pode ser gênero-dependente. Foram analisadas amostras de DNA de 52 pacientes com EM reincidente-remitente (EMRR) e 126 controles saudáveis ​​pareados por sexo e idade. Foi identificada associação significativa HLA-DRB1*15:01-EMRR, que foi específica para o gênero feminino (Odds Ratio (OR) = 4,78, p = 0,001). Além disso, observou-se que o polimorfismo +1614 G/C, em combinação com o alelo HLA-DRB1*15:01 provoca o aumento da susceptibilidade à EM em pacientes do sexo feminino (OR = 4,55, p = 0,01). Juntos, estes resultados destacam a natureza poligênica da EM.

The impact of diagnostic criteria for neuromyelitis optica in patients with MS: a 10-year follow-up of the South Atlantic Project.

BACKGROUND: It is recognized that there is a particular geographic and ethnic distribution of neuromyelitis optica (NMO) among Caucasian and non-Caucasian populations. OBJECTIVE: To review the diagnoses of patients whom were enrolled in the South Atlantic Project, a Brazilian multiple sclerosis (MS) survey performed from 1995-1998, and to identify NMO and MS case frequencies. METHODS: We reviewed the data from a 10-year follow-up of MS patients. To apply the current diagnostic criteria, the neurologists were asked to collect clinical and laboratory data from the medical records of study patients treated from 1999-2009. RESULTS: The spectrum of inflammatory demyelinating disease in 322 patients (67% white; 33% African-Brazilian) was: 49 (15%) with NMO; 14 (4%) with NMO syndromes; 10 (3%) with acute disseminated encephalomyelitis (ADEM); one isolated tumefactive brain lesion; 249 (77%) with MS (151 with relapsing-remitting MS (RRMS), 70 with secondary progressive MS (SPMS) and 27 with primary progressive MS (PPMS)). Disability was more severe in NMO and PPMS. One-third of the NMO patients had died. CONCLUSIONS: The frequency of NMO was 6.8% in São Paulo and 20.5% in Rio de Janeiro, and mainly seen in persons of African descent, which strengthens the hypothesis of there being an ethnic association of this disease. We recommend that epidemiological studies on MS that were performed previously be reviewed again, to ensure more accurate diagnoses.