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1.
Mol Cell Proteomics ; 22(1): 100478, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36470533

RESUMO

To date, very few mass spectrometry (MS)-based proteomics studies are available on the anterior and posterior lobes of the pituitary. In the past, MS-based investigations have focused exclusively on the whole pituitary gland or anterior pituitary lobe. In this study, for the first time, we performed a deep MS-based analysis of five anterior and five posterior matched lobes to build the first lobe-specific pituitary proteome map, which documented 4090 proteins with isoforms, mostly mapped into chromosomes 1, 2, and 11. About 1446 differentially expressed significant proteins were identified, which were studied for lobe specificity, biological pathway enrichment, protein-protein interaction, regions specific to comparison of human brain and other neuroendocrine glands from Human Protein Atlas to identify pituitary-enriched proteins. Hormones specific to each lobe were also identified and validated with parallel reaction monitoring-based target verification. The study identified and validated hormones, growth hormone and thyroid-stimulating hormone subunit beta, exclusively to the anterior lobe whereas oxytocin-neurophysin 1 and arginine vasopressin to the posterior lobe. The study also identified proteins POU1F1 (pituitary-specific positive transcription factor 1), POMC (pro-opiomelanocortin), PCOLCE2 (procollagen C-endopeptidase enhancer 2), and NPTX2 (neuronal pentraxin-2) as pituitary-enriched proteins and was validated for their lobe specificity using parallel reaction monitoring. In addition, three uPE1 proteins, namely THEM6 (mesenchymal stem cell protein DSCD75), FSD1L (coiled-coil domain-containing protein 10), and METTL26 (methyltransferase-like 26), were identified using the NeXtProt database, and depicted tumor markers S100 proteins having high expression in the posterior lobe. In summary, the study documents the first matched anterior and posterior pituitary proteome map acting as a reference control for a better understanding of functional and nonfunctional pituitary adenomas and extrapolating the aim of the Human Proteome Project towards the investigation of the proteome of life.


Assuntos
Adeno-Hipófise , Neuro-Hipófise , Humanos , Proteoma/metabolismo , Adeno-Hipófise/metabolismo , Hipófise/metabolismo , Neuro-Hipófise/metabolismo
2.
J Neurochem ; 167(2): 218-247, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37694499

RESUMO

Traumatic brain injury (TBI) causes significant neurological deficits and long-term degenerative changes. Primary injury in TBI entails distinct neuroanatomical zones, i.e., contusion (Ct) and pericontusion (PC). Their dynamic expansion could contribute to unpredictable neurological deterioration in patients. Molecular characterization of these zones compared with away from contusion (AC) zone is invaluable for TBI management. Using proteomics-based approach, we were able to distinguish Ct, PC and AC zones in human TBI brains. Ct was associated with structural changes (blood-brain barrier (BBB) disruption, neuroinflammation, axonal injury, demyelination and ferroptosis), while PC was associated with initial events of secondary injury (glutamate excitotoxicity, glial activation, accumulation of cytoskeleton proteins, oxidative stress, endocytosis) and AC displayed mitochondrial dysfunction that could contribute to secondary injury events and trigger long-term degenerative changes. Phosphoproteome analysis in these zones revealed that certain differentially phosphorylated proteins synergistically contribute to the injury events along with the differentially expressed proteins. Non-synaptic mitochondria (ns-mito) was associated with relatively more differentially expressed proteins (DEPs) compared to synaptosomes (Syn), while the latter displayed increased protein oxidation including tryptophan (Trp) oxidation. Proteomic analysis of immunocaptured complex I (CI) from Syn revealed increased Trp oxidation in Ct > PC > AC (vs. control). Oxidized W272 in the ND1 subunit of CI, revealed local conformational changes in ND1 and the neighboring subunits, as indicated by molecular dynamics simulation (MDS). Taken together, neuroanatomical zones in TBI show distinct protein profile and protein oxidation representing different primary and secondary injury events with potential implications for TBI pathology and neurological status of the patients.

3.
J Med Virol ; 95(9): e29110, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37728394

RESUMO

Rabies, a lethal zoonotic encephalitis, remains a significant global health concern, causing an estimated 60 000 annual fatalities worldwide. Dogs serve as the primary reservoirs and vectors for transmitting this infection to humans. Definitive diagnosis of rabies in both human and animal cases necessitates laboratory testing involving various clinical specimens. However, the complexity of laboratory infrastructure and the need for skilled personnel, along with the challenge of maintaining cold-chain integrity during sample referral, hinder the decentralization of diagnostic facilities. This study aimed to assess the efficacy of the Truenat rabies assay, a rapid, portable, semiautomated, and closed PCR-based system, for the diagnosis of rabies in both humans and animals. The Truenat assay demonstrated a sensitivity of 100% and a specificity of 86.96% when compared with the fluorescent antibody test (FAT), as the reference standard, on 147 canine brain samples tested. Notably, the Truenat assay exhibited a sensitivity and specificity of 100% when tested on 48 human brain specimens. Furthermore, an examination of 148 human antemortem samples (cerebrospinal fluid, saliva, and skin biopsy) using both the Truenat assay and a validated real-time reverse transcriptase PCR assay revealed a κ value of 0.505, indicative of a moderate level of agreement between the two tests. Thus, the Truenat assay offers a robust, reliable, and affordable point-of-care solution to enhance rabies diagnostic capacity in endemic areas.


Assuntos
Vírus da Raiva , Raiva , Humanos , Cães , Animais , Vírus da Raiva/genética , Raiva/diagnóstico , Raiva/veterinária , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Bioensaio , Biópsia
4.
Cytotherapy ; 25(11): 1200-1211, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37642606

RESUMO

BACKGROUND AIMS: Mesenchymal stromal cell (MSC) therapy for diabetic neuropathy (DN) has been extensively researched in vitro and in pre-clinical studies; however, the clinical scenario thus far has been disappointing. Temporary recovery, a common feature of these studies, indicates that either the retention of transplanted cells deteriorates with time or recovery of supportive endogenous cells, such as bone marrow-derived MSCs (BM-MSCs), does not occur, requiring further replenishment. In DN, BM-MSCs are recognized mediators of Schwann cell regeneration, and we have earlier shown that they suffer impairment in the pre-neuropathy stage. In this study, we attempted to further elucidate the mechanisms of functional recovery by focusing on changes occurring at the cellular level in the sciatic nerve, in conjunction with the biodistribution and movement patterns of the transplanted cells, to define the interval between doses. METHOD & RESULTS: We found that two doses of 1 × 106 dental pulp stromal cells (DPSCs) transplanted intramuscularly at an interval of 4 weeks effectively improved nerve conduction velocity (NCV) and restored motor coordination through improving sciatic nerve architecture, Schwann cell survival and myelination. Despite very minimal recovery of endogenous BM-MSCs, a temporary restoration of NCV and motor function was achieved with the first dose of DPSC transplantation. However, this did not persist, and a repeat dose was needed to consolidate functional improvement and rehabilitate the sciatic nerve architecture. CONCLUSION: Thus, repeat intramuscular transplantation of DPSCs is more effective for maintenance of Schwann cell survival and myelination for functional recovery after onset of DN.


Assuntos
Diabetes Mellitus , Neuropatias Diabéticas , Humanos , Neuropatias Diabéticas/terapia , Sobrevivência Celular , Polpa Dentária , Distribuição Tecidual , Células de Schwann , Células Estromais , Nervo Isquiático , Regeneração Nervosa/fisiologia
5.
Clin Neuropathol ; 42(3): 100-111, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37051870

RESUMO

BACKGROUND: Inflammatory myofibroblastic tumors (IMTs) are a distinct entity of mesenchymal tumors. We present the challenges in their diagnosis and management. MATERIALS AND METHODS: A retrospective study with detailed clinical, radiological, and histopathological (HPE) features along with management and outcome of 10 biopsy-proven patients with IMT, between 2001 and 2020. RESULTS: The location included intracranial (5), orbital (4), and spinal (1) with M : F = 7 : 3. The mean age of onset was in the third decade. The commonest symptom was headache, while proptosis and blurred vision occurred in orbital IMTs. HPE revealed diffuse infiltration of mixed inflammatory cells over proliferating myofibroblasts. Smooth muscle antigen immunoreactivity was noted in fibroblastic spindle cells of all IMTs. However, we did not find anaplastic lymphoma kinase expression in any of our cases, as this is only found in ~ 50% of all IMTs. Tumor infiltration into adjacent tissue was noted in 4 patients. Surgical excision was limited to orbital IMTs, as most central nervous system (CNS) tumors were not amenable for resection. Steroid administration showed moderate improvement in the IMT-CNS patients but also required additional immunomodulation. Four patients had a median long-term follow-up of 7 years. Two patients had recurrent lesions demonstrated by imaging after 2 years of initial presentation. CONCLUSION: IMTs are rare and ambiguous tumors of unknown etiology that can occur anywhere in the body. Clinical and radiological features may not be specific to determine the diagnosis, but it should be considered as a differential diagnosis. Extensive thorough workup with histopathology along with the help of immunohistochemistry is conducive to better clinical outcomes. Surgical biopsy with extensive and total resection of these tumors along with steroid and radiotherapy may enhance the survival outcomes.


Assuntos
Neoplasias do Sistema Nervoso Central , Granuloma de Células Plasmáticas , Humanos , Estudos Retrospectivos , Neoplasias do Sistema Nervoso Central/patologia , Granuloma de Células Plasmáticas/diagnóstico , Granuloma de Células Plasmáticas/terapia , Granuloma de Células Plasmáticas/metabolismo , Imuno-Histoquímica
6.
J Acoust Soc Am ; 154(6): 3833-3841, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-38109407

RESUMO

Hermite-scan (H-scan) imaging is a tissue characterization technique based on the analysis of raw ultrasound radio frequency (RF) echoes. It matches the RF echoes to Gaussian-weighted Hermite polynomials of various orders to extract information related to scatterer diameter. It provides a color map of large and small scatterers in the red and blue H-scan image channels, respectively. H-scan has been previously reported for characterizing breast, pancreatic, and thyroid tumors. The present work evaluated H-scan imaging to differentiate glioblastoma tumors from normal brain tissue ex vivo. First, we conducted 2-D numerical simulations using the k-wave toolbox to assess the performance of parameters derived from H-scan images of acoustic scatterers (15-150 µm diameters) and concentrations (0.2%-1% w/v). We found that the parameter intensity-weighted percentage of red (IWPR) was sensitive to changes in scatterer diameters independent of concentration. Next, we assessed the feasibility of using the IWPR parameter for differentiating glioblastoma and normal brain tissues (n = 11 samples per group). The IWPR parameter estimates for normal tissue (44.1% ± 1.4%) were significantly different (p < 0.0001) from those for glioblastoma (36.2% ± 0.65%). These findings advance the development of H-scan imaging for potential use in differentiating glioblastoma tumors from normal brain tissue during resection surgery.


Assuntos
Glioblastoma , Humanos , Glioblastoma/diagnóstico por imagem , Ultrassonografia/métodos , Distribuição Normal , Algoritmos , Encéfalo/diagnóstico por imagem
7.
Int J Neurosci ; : 1-13, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37824719

RESUMO

OBJECTIVES: This study aimed to localise the eloquent cortex and measure evoked field (EF) parameters using magnetoencephalography in patients with epilepsy and tumours near the eloquent cortex. METHODS: A total of 41 patients (26 with drug-refractory epilepsy and 15 with tumours), with a mean age of 33 years, were recruited. Visual evoked field (VEF), auditory evoked field (AEF), sensory evoked field (SSEF), and motor-evoked field (MEF) latencies, amplitudes, and localisation were compared with those of a control population. Subgroup analyses were performed based on lobar involvement. Evoked Field parameters on the affected side were compared with those on the opposite side. The effect of distance from the lesion on nearby and distant evoked fields was evaluated. RESULTS: AEF and VEF amplitudes and latencies were reduced bilaterally (p < 0.05). Amplitude in the ipsilateral SSEF was reduced by 29.27% and 2.16% in the AEF group compared to the contralateral side (p = 0.02). In patients with temporal lobe lesions, the SSEF amplitude was reduced bilaterally (p < 0.02), and latency was prolonged compared with controls. The MEF amplitude was reduced and latency was prolonged in patients with frontal lobe lesions (p = 0.01). EF displacement was 32%, 57%, 21%, and 16% for AEF, MEF, VEF, and SSEF respectively. Patients in the epilepsy group had distant EF abnormalities. CONCLUSIONS: EF amplitude was reduced and latency was prolonged in the involved hemisphere. Distant EF amplitudes were more affected than latencies in epilepsy. Amplitude and distance from the lesion had negative correlation for all EF. EF changes indicated eloquent cortical displacement which may not be apparent on MRI.

8.
J Cancer Educ ; 38(3): 985-990, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36151353

RESUMO

Medical student exposure to oncology is imperative given the prevalence of cancer, growing need for survivorship care, and ever-evolving therapies. Our institution offers a Cancer Care Elective for undergraduate medical students focused on clinical shadowing, but the COVID-19 pandemic necessitated completely redesigning a virtual alternative. In this study, we utilize a post-elective survey to 1) assess whether the novel virtual elective effectively promoted student learning and 2) identify which components were most impactful. We created an entirely virtual, semester-long course with structured mentorship, subspecialty panels, physician-led didactics, and patient exposure. Students attended multidisciplinary tumor boards and presented on oncologic topics. A post-elective survey assessed the course's impact on students' knowledge and the perceived value of each elective component. Of the 29 enrolled students, 12 responded to our survey (41%). Most students reported that the elective highly enhanced their understanding of medical (67%), surgical (75%), and pediatric (66%) oncology. The highest rated didactic involved patients discussing their cancer journeys, with 80% of students reporting that this session enhanced their understanding of patient-physician collaboration. Students reported that physician mentorship helped them better understand oncology (90%) and promoted interest in pursuing an oncologic career (100%). This study demonstrates that our virtual Cancer Care Elective was effective at increasing student understanding of oncology in practice. The results also suggest that patient exposure and physician mentorship are particularly educational and encouraging.


Assuntos
COVID-19 , Educação de Graduação em Medicina , Estudantes de Medicina , Humanos , Criança , Pandemias , COVID-19/epidemiologia , Educação de Graduação em Medicina/métodos , Currículo
9.
J Proteome Res ; 21(10): 2293-2310, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36039803

RESUMO

Background: Distinct hippocampal subfields are known to get affected during aging, psychiatric disorders, and various neurological and neurodegenerative conditions. To understand the biological processes associated with each subfield, it is important to understand its heterogeneity at the molecular level. To address this lacuna, we investigated the proteomic analysis of hippocampal subfields─the cornu ammonis sectors (CA1, CA2, CA3, CA4) and dentate gyrus (DG) from healthy adult human cohorts. Findings: Microdissection of hippocampal subfields from archived formalin-fixed paraffin-embedded tissue sections followed by TMT-based multiplexed proteomic analysis resulted in the identification of 5,593 proteins. Out of these, 890 proteins were found to be differentially abundant among the subfields. Further bioinformatics analysis suggested proteins related to gene splicing, transportation, myelination, structural activity, and learning processes to be differentially abundant in DG, CA4, CA3, CA2, and CA1, respectively. A subset of proteins was selected for immunohistochemistry-based validation in an independent set of hippocampal samples. Conclusions: We believe that our findings will effectively pave the way for further analysis of the hippocampal subdivisions and provide awareness of its subfield-specific association to various neurofunctional anomalies in the future. The current mass spectrometry data is deposited and publicly made available through ProteomeXchange Consortium via the PRIDE partner repository with the data set identifier PXD029697.


Assuntos
Imageamento por Ressonância Magnética , Proteômica , Adulto , Envelhecimento , Formaldeído , Hipocampo , Humanos , Imageamento por Ressonância Magnética/métodos
10.
Neurochem Res ; 47(6): 1610-1636, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35229271

RESUMO

Rabies is a fatal encephalitis caused by the Rabies lyssavirus (RABV). The presence of minimal neuropathological changes observed in rabies indicates that neuronal dysfunction, rather than neuronal death contributes to the fatal outcome. The role of mitochondrial changes has been suggested as a possible mechanism for neuronal dysfunction in rabies. However, these findings are mostly based on studies that have employed experimental models and laboratory-adapted virus. Studies on brain tissues from naturally infected human and animal hosts are lacking. The current study investigated the role of mitochondrial changes in rabies by morphological, biochemical and proteomic analysis of RABV-infected human and canine brains. Morphological analysis showed minimal inflammation with preserved neuronal and disrupted mitochondrial structure in both human and canine brains. Proteomic analysis revealed involvement of mitochondrial processes (oxidative phosphorylation, cristae formation, homeostasis and transport), synaptic proteins and autophagic pathways, with over-expression of subunits of mitochondrial respiratory complexes. Consistent with these findings, human and canine brains displayed elevated activities of complexes I (p < 0.05), IV (p < 0.05) and V (p < 0.05). However, this did not result in elevated ATP production (p < 0.0001), probably due to lowered mitochondrial membrane potential as noted in RABV-infected cells in culture. These could lead to mitochondrial dysfunction and mitophagy as indicated by expression of FKBP8 (p < 0.05) and PINK1 (p < 0.001)/PARKIN (p > 0.05) and ensuing autophagy, as shown by the status of LCIII (p < 0.05), LAMP1 (p < 0.001) and pertinent ultrastructural markers. We propose that altered mitochondrial bioenergetics and cristae architecture probably induce mitophagy, leading to autophagy and consequent neuronal dysfunction in rabies.


Assuntos
Vírus da Raiva , Raiva , Animais , Encéfalo/metabolismo , Cães , Humanos , Mitocôndrias/metabolismo , Proteômica , Raiva/metabolismo , Raiva/patologia , Vírus da Raiva/fisiologia
11.
Clin Neuropathol ; 41(1): 18-24, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34142952

RESUMO

INTRODUCTION: Hypothalamic hamartoma (HH) is a rare developmental disorder presenting with gelastic seizures or precocious puberty attributed to gonadotrophin-releasing hormone expression by the hamartoma. The histogenesis of HH is uncertain, and diagnosis of HH is difficult in small biopsies due to its close resemblance to normal hypothalamic nuclei. TTF-1 and arginine vasopressin (AVP) are associated with gonadotropin-releasing hormone release. MATERIALS AND METHODS: In this study, we explored the expression pattern of TTF-1 and AVP in HH and its utility, if any, in diagnosis. We reviewed the clinical, radiologic, and histopathological features of 23 HH diagnosed over the past decade at our Institute. RESULTS: The age at presentation ranged from 11 months to 34 years with gelastic seizures (82.6%), precocious puberty (17.4%), and developmental delay (8.7%) as presenting symptoms. On imaging, all the lesions (n = 9) involved the posterior and tuberal group of hypothalamic nuclei, while 5 cases involved the anterior hypothalamus. Anatomically, the lesions involved mammillary body, arcuate and periventricular nuclei. On histopathology, 52% cases revealed nodular arrangement of small neurocytic cells separated by glial stroma. TTF-1 and AVP immunoreactivity was absent in all the cases, whereas in normal hypothalamus, AVP was expressed in periventricular nuclei. CONCLUSION: Our results suggest that immunoexpression of TTF-1 is absent in HH, particularly in those arising from the posterior hypothalamus, and this can be used in small biopsies to distinguish from a normal hypothalamus as well as from posterior pituitary tumors.


Assuntos
Proteínas de Ligação a DNA , Hamartoma , Doenças Hipotalâmicas , Neurofisinas , Precursores de Proteínas , Puberdade Precoce , Fatores de Transcrição , Vasopressinas , Arginina Vasopressina , Proteínas de Ligação a DNA/imunologia , Hamartoma/diagnóstico , Humanos , Doenças Hipotalâmicas/diagnóstico , Lactente , Neurofisinas/imunologia , Precursores de Proteínas/imunologia , Fatores de Transcrição/imunologia , Vasopressinas/imunologia
12.
Emerg Radiol ; 29(4): 791-799, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35482173

RESUMO

Infectious diseases affecting the central nervous system remain an important cause of morbidity and mortality in developing countries and in immunocompromised patients. Cerebritis refers to pyogenic inflammation of the brain parenchyma that may lead to abscess formation if left untreated. Cerebritis is an uncommon diagnosis as patients are usually diagnosed at the stage of abscess formation. We present three cases of bacterial cerebritis with different clinical manifestations and varied appearances on MRI. To our knowledge, only few case reports of bacterial cerebritis have been published in the literature, and imaging findings are not fully elucidated. These cases of bacterial cerebritis add valuable information to the existing literature and would be helpful in making the appropriate diagnosis of this uncommon condition that can be medically managed if diagnosed appropriately. We recommend that cerebritis should be considered in the differential diagnosis of such lesions.


Assuntos
Abscesso Encefálico , Encéfalo/patologia , Abscesso Encefálico/diagnóstico por imagem , Abscesso Encefálico/tratamento farmacológico , Diagnóstico Diferencial , Humanos , Imageamento por Ressonância Magnética
13.
Epilepsia ; 62(6): 1416-1428, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33949696

RESUMO

OBJECTIVE: Focal cortical dysplasia (FCD) is a major cause of difficult-to-treat epilepsy in children and young adults, and the diagnosis is currently based on microscopic review of surgical brain tissue using the International League Against Epilepsy classification scheme of 2011. We developed an iterative histopathological agreement trial with genetic testing to identify areas of diagnostic challenges in this widely used classification scheme. METHODS: Four web-based digital pathology trials were completed by 20 neuropathologists from 15 countries using a consecutive series of 196 surgical tissue blocks obtained from 22 epilepsy patients at a single center. Five independent genetic laboratories performed screening or validation sequencing of FCD-relevant genes in paired brain and blood samples from the same 22 epilepsy patients. RESULTS: Histopathology agreement based solely on hematoxylin and eosin stainings was low in Round 1, and gradually increased by adding a panel of immunostainings in Round 2 and the Delphi consensus method in Round 3. Interobserver agreement was good in Round 4 (kappa = .65), when the results of genetic tests were disclosed, namely, MTOR, AKT3, and SLC35A2 brain somatic mutations in five cases and germline mutations in DEPDC5 and NPRL3 in two cases. SIGNIFICANCE: The diagnoses of FCD 1 and 3 subtypes remained most challenging and were often difficult to differentiate from a normal homotypic or heterotypic cortical architecture. Immunohistochemistry was helpful, however, to confirm the diagnosis of FCD or no lesion. We observed a genotype-phenotype association for brain somatic mutations in SLC35A2 in two cases with mild malformation of cortical development with oligodendroglial hyperplasia in epilepsy. Our results suggest that the current FCD classification should recognize a panel of immunohistochemical stainings for a better histopathological workup and definition of FCD subtypes. We also propose adding the level of genetic findings to obtain a comprehensive, reliable, and integrative genotype-phenotype diagnosis in the near future.


Assuntos
Malformações do Desenvolvimento Cortical/diagnóstico por imagem , Malformações do Desenvolvimento Cortical/patologia , Adolescente , Adulto , Idade de Início , Diversidade de Anticorpos , Encéfalo/patologia , Criança , Pré-Escolar , Técnica Delphi , Feminino , Genótipo , Humanos , Imuno-Histoquímica , Lactente , Imageamento por Ressonância Magnética , Masculino , Malformações do Desenvolvimento Cortical/cirurgia , Pessoa de Meia-Idade , Mutação/genética , Procedimentos Neurocirúrgicos , Variações Dependentes do Observador , Fenótipo , Convulsões/etiologia , Adulto Jovem
14.
Dement Geriatr Cogn Disord ; 50(2): 153-160, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34237731

RESUMO

OBJECTIVE: In the background of an emerging role for immune dysregulation in neurodegenerative dementias, this study aimed to investigate the relationship between systemic autoimmunity and dementia. The objective was to study the frequency and profile of disease-specific autoantibodies in Alzheimer's dementia (AD), frontotemporal dementia (FTD), and dementia with Lewy bodies (DLB). METHODS: Immunological testing was performed in a large cohort of neurodegenerative dementia diagnosed based on standard clinical and imaging criteria. Patients were evaluated for the presence of autoantibodies specific for systemic autoimmune diseases that included anti-extractable nuclear antibody profile, rheumatoid factor antibody (RA), perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA), and cytoplasmic anti-neutrophil cytoplasmic antibody (c-ANCA) in serum. RESULTS: Of 174 patients with degenerative dementia (FTD = 114, AD = 53, and DLB = 7) evaluated with immunological testing, 18.9% (n = 33) were seropositive for autoantibodies. The common antibodies detected were anti-Scl-70 (25%), anti-Ro-52 (18.7%), anti-nRNP-Sm (12.5%), and anti-CENP-B (9.3%). There were no significant systemic complaints in the majority of patients. A wider range of antibodies were positive in FTD compared to AD and DLB. While no difference was observed in the mean age, sex, or duration of illness between seropositive and negative patients, family history of dementia was more frequent among seronegative patients. CONCLUSION: Our findings indicate an emerging role for immune dysregulation in patients with classical neurodegenerative dementias, especially those with FTD. These autoantibodies could play a role in immune degradation of protein aggregates that characterize neurodegeneration. Study findings emphasize the need to explore the complex relationship between systemic autoimmunity and neurodegenerative dementia.


Assuntos
Doença de Alzheimer , Demência Frontotemporal , Doença por Corpos de Lewy , Doença de Pick , Doença de Alzheimer/diagnóstico , Autoanticorpos , Demência Frontotemporal/diagnóstico , Humanos
15.
J Immunol ; 203(8): 2222-2238, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31527198

RESUMO

Microglia being the resident macrophage of brain provides neuroprotection following diverse microbial infections. Japanese encephalitis virus (JEV) invades the CNS, resulting in neuroinflammation, which turns the neuroprotective role of microglia detrimental as characterized by increased microglial activation and neuronal death. Several host factors, including microRNAs, play vital roles in regulating virus-induced inflammation. In the current study, we demonstrate that the expression of miR-301a is increased in JEV-infected microglial cells and human brain. Overexpression of miR-301a augments the JEV-induced inflammatory response, whereas inhibition of miR-301a completely reverses the effects. Mechanistically, NF-κB-repressing factor (NKRF) functioning as inhibitor of NF-κB activation is identified as a potential target of miR-301a in JEV infection. Consequently, miR-301a-mediated inhibition of NKRF enhances nuclear translocation of NF-κB, which, in turn, resulted in amplified inflammatory response. Conversely, NKRF overexpression in miR-301a-inhibited condition restores nuclear accumulation of NF-κB to a basal level. We also observed that JEV infection induces classical activation (M1) of microglia that drives the production of proinflammatory cytokines while suppressing alternative activation (M2) that could serve to dampen the inflammatory response. Furthermore, in vivo neutralization of miR-301a in mouse brain restores NKRF expression, thereby reducing inflammatory response, microglial activation, and neuronal apoptosis. Thus, our study suggests that the JEV-induced expression of miR-301a positively regulates inflammatory response by suppressing NKRF production, which might be targeted to manage viral-induced neuroinflammation.


Assuntos
Antivirais/farmacologia , Vírus da Encefalite Japonesa (Espécie)/efeitos dos fármacos , Vírus da Encefalite Japonesa (Espécie)/imunologia , Encefalite Japonesa/tratamento farmacológico , Encefalite Japonesa/imunologia , Interferon beta-1b/farmacologia , MicroRNAs/metabolismo , Proteínas Repressoras/antagonistas & inibidores , Animais , Células Cultivadas , Vírus da Encefalite Japonesa (Espécie)/metabolismo , Encefalite Japonesa/metabolismo , Feminino , Humanos , Inflamação/genética , Inflamação/imunologia , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/genética , Proteínas Repressoras/metabolismo
16.
Neurol Sci ; 42(11): 4683-4696, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33728548

RESUMO

OBJECTIVES: We aimed to (i) analyse the clinical characteristics, treatment outcome and long-term prognosis of anti-NMDAR encephalitis and (ii) study the differences between paediatric and adult patients. METHODS: This was a chart review of all patients with anti-NMDAR encephalitis. RESULTS: There were 28 patients with 18 patients belonging to the paediatric (<18 years) age group. There was female (94%) preponderance in the paediatric age group, while in adult patients, there was no gender predilection (p=0.006). There was no significant difference in clinical feature, outcome or number of relapses between paediatric and adult population groups. MRI brain was abnormal in 53% of patients. Among the 15 patients with MRI abnormalities at the onset, 53% had poor functional outcome at 1 year, while in 12 patients with normal initial MRI brain, only 8% had poor functional outcome at 1 year (p =0.01). Nearly 53% of patients with abnormal MRI at presentation had at least one clinical relapse within 2 years while in patients with normal MRI at presentation, 15% had a clinical relapse (p=0.037). EEG abnormalities were noticed in 71% of patients; among them, 40 and 15% had poor functional outcome at 1 and 2 years respectively. In comparison, those with normal first EEG at onset, 12% had poor functional outcome at 2 years (p=0.57). CONCLUSIONS: Both paediatric and adult patients presented with similar clinical features but the paediatric population had female preponderance. The functional outcome and number of relapse were comparable in both the paediatric and adult groups. Patients with parenchymal changes on MRI and abnormal EEG showed poorer response compared to those with normal MRI and/or EEG at the onset. Patients have lesser severity of symptoms at relapse than in the first episode. An early diagnosis and treatment are essential for better long-term functional outcome.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato , Adulto , Encefalite Antirreceptor de N-Metil-D-Aspartato/diagnóstico por imagem , Encefalite Antirreceptor de N-Metil-D-Aspartato/terapia , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Recidiva Local de Neoplasia , Prognóstico , Resultado do Tratamento
17.
Pediatr Neurosurg ; 56(6): 538-548, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34649244

RESUMO

BACKGROUND: Posterior quadrant disconnection (PQD) is an under-utilized surgical technique in the management of refractory epilepsy. There is a dearth of data pertinent to post-PQD seizure outcomes. METHODS: This retrospective study analyzed patients with drug-resistant childhood-onset epilepsy who underwent PQD at our center from 2009 to 2018. The clinical, imaging, and electrophysiological data were reviewed. The seizure outcome was noted from the latest follow-up in all patients. RESULTS: Fifteen patients underwent PQD, with a mean age at onset of epilepsy of 3.3 ± 4.6 years. All patients had seizure onset in childhood with focal onset of seizures, and in addition, 5 had multiple seizure types. All cases underwent presurgical workup with MRI, video-EEG, psychometry, while PET/MEG was done if required. Engel Ia and ILAE I outcomes were considered to be favorable. The histology of the specimen showed 9 patients (60%) had gliosis, 4 (26.7%) had focal cortical dysplasia (FCD), while 1 patient had nodular heterotopia and another had polymicrogyria-pachygyria complex. Postoperative follow-up was available in 14 cases. One patient was lost to follow-up. Mean follow-up duration for the cohort was 45 + 24 months. At last, follow-up (n = 14), 66.7% (10 cases) had favorable outcome (Engel Ia). At the end of 1-year follow-up, up to 73% (n = 11) of the patients were seizure-free. Four patients developed transient hemiparesis after surgery which improved completely by 3-6 months. CONCLUSIONS: Gliosis was more common etiology requiring PQD in our series than Western series, where FCD was more common. PQD is a safe and effective surgical modality in childhood-onset epilepsy with posterior head region epileptogenic focus.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/cirurgia , Eletroencefalografia , Humanos , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Resultado do Tratamento
18.
Muscle Nerve ; 62(6): 728-734, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32939766

RESUMO

BACKGROUND: Antibodies against ganglioside complexes (GSCs) are associated with various clinical features and subtypes of Guillain-Barré syndrome (GBS). METHODS: One-hundred patients were evaluated for antibodies to GSCs formed by combination of GM1, GM2, GD1a, GD1b, GT1b, and GQ1b using manual enzyme linked immuno-sorbent assay (ELISA). RESULTS: Twenty-six patients were GSC antibody-positive, most frequent being against GM1-containing GSC (76.9%). Gender distribution, mean age, symptom-duration, antecedent events, electrophysiological subtypes, requirement for mechanical ventilation, and median duration of hospital stay were comparable between the GSC antibody-positive and negative groups. There was no association between specific GSC antibody and electrophysiological subtypes or clinical variants. After controlling for false discovery rate (FDR) using the Benjamini-Hochberg method, the number of subjects who improved in overall disability sum score, modified Erasmus GBS outcome score, and neuropathy symptom score at discharge was significantly higher in the GSC antibody-positive group. Improvements in Medical Research Council sum scores and Hughes Disability Scale during the hospital stay between the GSC antibody-positive and negative groups were not significantly different after controlling for FDR. CONCLUSIONS: The GSC antibody-positive group had better outcome at hospital discharge in some of the disability scores. Pathophysiological pathways among patients without GSC antibodies may be different and this requires further evaluation.


Assuntos
Autoanticorpos/imunologia , Gangliosídeos/imunologia , Síndrome de Guillain-Barré/imunologia , Adolescente , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática , Feminino , Gangliosídeo G(M1)/imunologia , Gangliosídeo G(M2)/imunologia , Síndrome de Guillain-Barré/fisiopatologia , Síndrome de Guillain-Barré/terapia , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Fatores Imunológicos/uso terapêutico , Índia , Masculino , Pessoa de Meia-Idade , Plasmaferese , Respiração Artificial , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
19.
Rev Med Virol ; 29(5): e2058, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31237061

RESUMO

Subacute sclerosing panencephalitis (SSPE) is a slowly progressive brain disorder caused by mutant measles virus. SSPE affects younger age groups. SSPE incidence is proportional to that of measles. High-income countries have seen substantial decline in SSPE incidence following universal vaccination against measles. SSPE virus differs from wild measles virus. Measles virus genome recovered from the autopsied brain tissues demonstrates clustered mutations in virus genome particularly in the M gene. These mutations destroy the structure and functioning of the encoded proteins. Complete infectious virus particle has rarely been recovered from the brain. Human neurons lack required receptor for entry of measles virus inside the neurons. Recent in vitro studies suggest that mutations in F protein confer hyperfusogenic properties to measles virus facilitating transneuronal viral spread. The inflammatory response in the brain leads to extensive tissue damage. Clinically, SSPE is characterized by florid panencephalitis. Clinically, SSPE is characterized by cognitive decline, periodic myoclonus, gait abnormalities, vision loss, and ultimately to a vegetative state. Chorioretinitis is a common ocular abnormality. Electroencephalography (EEG) shows characteristic periodic discharges. Neuroimaging demonstrates periventricular white matter signal abnormalities. In advanced stages, there is marked cerebral atrophy. Definitive diagnosis requires demonstration of elevated measles antibody titers in cerebrospinal fluid (CSF). Many drugs have been used to stabilize the course of the disease but without evidence from randomized clinical trials. Six percent of patients may experience prolonged spontaneous remission. Fusion inhibitor peptide may, in the future, be exploited to treat SSPE. A universal vaccination against measles is the only proven way to tackle this menace currently.


Assuntos
Panencefalite Esclerosante Subaguda/diagnóstico , Panencefalite Esclerosante Subaguda/etiologia , Biomarcadores , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/virologia , Tronco Encefálico/diagnóstico por imagem , Tronco Encefálico/patologia , Tronco Encefálico/virologia , Diagnóstico Diferencial , Gerenciamento Clínico , Suscetibilidade a Doenças , Eletroencefalografia , Feminino , Predisposição Genética para Doença , Humanos , Imuno-Histoquímica , Vírus do Sarampo/fisiologia , Neuroimagem/métodos , Fenótipo , Gravidez , Prognóstico , Panencefalite Esclerosante Subaguda/epidemiologia , Panencefalite Esclerosante Subaguda/terapia , Internalização do Vírus
20.
Brain ; 142(11): 3514-3529, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31553044

RESUMO

In patients with medically refractory epilepsy, resective surgery is the mainstay of therapy to achieve seizure freedom. However, ∼20-50% of cases have intractable seizures post-surgery due to the imprecise determination of epileptogenic zone. Recent intracranial studies suggest that high frequency oscillations between 80 and 200 Hz could serve as one of the consistent epileptogenicity biomarkers for localization of the epileptogenic zone. However, these high frequency oscillations are not adopted in the clinical setting because of difficult non-invasive detection. Here, we investigated non-invasive detection and localization of high frequency oscillations and its clinical utility in accurate pre-surgical assessment and post-surgical outcome prediction. We prospectively recruited 52 patients with medically refractory epilepsy who underwent standard pre-surgical workup including magnetoencephalography (MEG) followed by resective surgery after determination of the epileptogenic zone. The post-surgical outcome was assessed after 22.14 ± 10.05 months. Interictal epileptic spikes were expertly identified, and interictal epileptic oscillations across the neural activity frequency spectrum from 8 to 200 Hz were localized using adaptive spatial filtering methods. Localization results were compared with epileptogenic zone and resected cortex for congruence assessment and validated against the clinical outcome. The concordance rate of high frequency oscillations sources (80-200 Hz) with the presumed epileptogenic zone and the resected cortex were 75.0% and 78.8%, respectively, which is superior to that of other frequency bands and standard dipole fitting methods. High frequency oscillation sources corresponding with the resected cortex, had the best sensitivity of 78.0%, positive predictive value of 100% and an accuracy of 78.84% to predict the patient's surgical outcome, among all other frequency bands. If high frequency oscillation sources were spatially congruent with resected cortex, patients had an odds ratio of 5.67 and 82.4% probability of achieving a favourable surgical outcome. If high frequency oscillations sources were discordant with the epileptogenic zone or resection area, patient has an odds ratio of 0.18 and only 14.3% probability of achieving good outcome, and mostly tended to have an unfavourable outcome (χ2 = 5.22; P = 0.02; φ = -0.317). In receiver operating characteristic curve analyses, only sources of high-frequency oscillations demonstrated the best sensitivity and specificity profile in determining the patient's surgical outcome with area under the curve of 0.76, whereas other frequency bands indicate a poor predictive performance. Our study is the first non-invasive study to detect high frequency oscillations, address the efficacy of high frequency oscillations over the different neural oscillatory frequencies, localize them and clinically validate them with the post-surgical outcome in patients with medically refractory epilepsy. The evidence presented in the current study supports the fact that HFOs might significantly improve the presurgical assessment, and post-surgical outcome prediction, where it could widely be used in a clinical setting as a non-invasive biomarker.


Assuntos
Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/cirurgia , Magnetoencefalografia/métodos , Neuroimagem/métodos , Procedimentos Neurocirúrgicos/métodos , Adolescente , Adulto , Biomarcadores , Mapeamento Encefálico , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/cirurgia , Estudos de Coortes , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Resultado do Tratamento , Adulto Jovem
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