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BACKGROUND AND OBJECTIVES: Degeneration of the presynaptic nigrostriatal dopaminergic system is one of the main biological features of Parkinson disease (PD), multiple system atrophy (MSA), progressive supranuclear palsy (PSP), and corticobasal degeneration (CBD), which can be measured using single-photon emission CT imaging for diagnostic purposes. Despite its widespread use in clinical practice and research, the diagnostic properties of presynaptic nigrostriatal dopaminergic (DAT) imaging in parkinsonism have never been evaluated against the diagnostic gold standard of neuropathology. The aim of this study was to evaluate the diagnostic parameters of DAT imaging compared with pathologic diagnosis in patients with parkinsonism. METHODS: Retrospective cohort study of patients with DAT imaging for the investigation of a clinically uncertain parkinsonism with brain donation between 2010 and 2021 to the Queen Square Brain Bank (London). Patients with DAT imaging for investigation of pure ataxia or dementia syndromes without parkinsonism were excluded. Those with a pathologic diagnosis of PD, MSA, PSP, or CBD were considered presynaptic dopaminergic parkinsonism, and other pathologies were considered postsynaptic for the analysis. DAT imaging was performed in routine clinical practice and visually classified by hospital nuclear medicine specialists as normal or abnormal. The results were correlated with neuropathologic diagnosis to calculate diagnostic accuracy parameters for the diagnosis of presynaptic dopaminergic parkinsonism. RESULTS: All of 47 patients with PD, 41 of 42 with MSA, 68 of 73 with PSP, and 6 of 10 with CBD (sensitivity 100%, 97.6%, 93.2%, and 60%, respectively) had abnormal presynaptic dopaminergic imaging. Eight of 17 patients with presumed postsynaptic parkinsonism had abnormal scans (specificity 52.9%). DISCUSSION: DAT imaging has very high sensitivity and negative predictive value for the diagnosis of presynaptic dopaminergic parkinsonism, particularly for PD. However, patients with CBD, and to a lesser extent PSP (of various phenotypes) and MSA (with predominant ataxia), can show normal DAT imaging. A range of other neurodegenerative disorders may have abnormal DAT scans with low specificity in the differential diagnosis of parkinsonism. DAT imaging is a useful diagnostic tool in the differential diagnosis of parkinsonism, although clinicians should be aware of its diagnostic properties and limitations. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that DAT imaging does not accurately distinguish between presynaptic dopaminergic parkinsonism and non-presynaptic dopaminergic parkinsonism.
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Proteínas da Membrana Plasmática de Transporte de Dopamina , Atrofia de Múltiplos Sistemas , Transtornos Parkinsonianos , Tomografia Computadorizada de Emissão de Fóton Único , Humanos , Feminino , Idoso , Masculino , Estudos Retrospectivos , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Transtornos Parkinsonianos/diagnóstico por imagem , Transtornos Parkinsonianos/patologia , Transtornos Parkinsonianos/metabolismo , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Pessoa de Meia-Idade , Atrofia de Múltiplos Sistemas/diagnóstico por imagem , Atrofia de Múltiplos Sistemas/patologia , Atrofia de Múltiplos Sistemas/metabolismo , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Paralisia Supranuclear Progressiva/patologia , Paralisia Supranuclear Progressiva/metabolismo , Idoso de 80 Anos ou mais , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Estudos de Coortes , Degeneração Corticobasal/diagnóstico por imagem , Degeneração Corticobasal/metabolismo , Dopamina/metabolismo , Terminações Pré-Sinápticas/metabolismo , Terminações Pré-Sinápticas/patologia , Sensibilidade e Especificidade , Imageamento DopaminérgicoRESUMO
BACKGROUND: Pick's disease is a rare and predominantly sporadic form of frontotemporal dementia that is classified as a primary tauopathy. Pick's disease is pathologically defined by the presence in the frontal and temporal lobes of Pick bodies, composed of hyperphosphorylated, three-repeat tau protein, encoded by the MAPT gene. MAPT has two distinct haplotypes, H1 and H2; the MAPT H1 haplotype is the major genetic risk factor for four-repeat tauopathies (eg, progressive supranuclear palsy and corticobasal degeneration), and the MAPT H2 haplotype is protective for these disorders. The primary aim of this study was to evaluate the association of MAPT H2 with Pick's disease risk, age at onset, and disease duration. METHODS: In this genetic association study, we used data from the Pick's disease International Consortium, which we established to enable collection of data from individuals with pathologically confirmed Pick's disease worldwide. For this analysis, we collected brain samples from individuals with pathologically confirmed Pick's disease from 35 sites (brainbanks and hospitals) in North America, Europe, and Australia between Jan 1, 2020, and Jan 31, 2023. Neurologically healthy controls were recruited from the Mayo Clinic (FL, USA, or MN, USA between March 1, 1998, and Sept 1, 2019). For the primary analysis, individuals were directly genotyped for the MAPT H1-H2 haplotype-defining variant rs8070723. In a secondary analysis, we genotyped and constructed the six-variant-defined (rs1467967-rs242557-rs3785883-rs2471738-rs8070723-rs7521) MAPT H1 subhaplotypes. Associations of MAPT variants and MAPT haplotypes with Pick's disease risk, age at onset, and disease duration were examined using logistic and linear regression models; odds ratios (ORs) and ß coefficients were estimated and correspond to each additional minor allele or each additional copy of the given haplotype. FINDINGS: We obtained brain samples from 338 people with pathologically confirmed Pick's disease (205 [61%] male and 133 [39%] female; 338 [100%] White) and 1312 neurologically healthy controls (611 [47%] male and 701 [53%] female; 1312 [100%] White). The MAPT H2 haplotype was associated with increased risk of Pick's disease compared with the H1 haplotype (OR 1·35 [95% CI 1·12 to 1·64], p=0·0021). MAPT H2 was not associated with age at onset (ß -0·54 [95% CI -1·94 to 0·87], p=0·45) or disease duration (ß 0·05 [-0·06 to 0·16], p=0·35). Although not significant after correcting for multiple testing, associations were observed at p less than 0·05: with risk of Pick's disease for the H1f subhaplotype (OR 0·11 [0·01 to 0·99], p=0·049); with age at onset for H1b (ß 2·66 [0·63 to 4·70], p=0·011), H1i (ß -3·66 [-6·83 to -0·48], p=0·025), and H1u (ß -5·25 [-10·42 to -0·07], p=0·048); and with disease duration for H1x (ß -0·57 [-1·07 to -0·07], p=0·026). INTERPRETATION: The Pick's disease International Consortium provides an opportunity to do large studies to enhance our understanding of the pathobiology of Pick's disease. This study shows that, in contrast to the decreased risk of four-repeat tauopathies, the MAPT H2 haplotype is associated with an increased risk of Pick's disease in people of European ancestry. This finding could inform development of isoform-related therapeutics for tauopathies. FUNDING: Wellcome Trust, Rotha Abraham Trust, Brain Research UK, the Dolby Fund, Dementia Research Institute (Medical Research Council), US National Institutes of Health, and the Mayo Clinic Foundation.
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Doença de Pick , Tauopatias , Feminino , Humanos , Masculino , Estudos de Associação Genética , Haplótipos , Doença de Pick/genética , Proteínas tau/genéticaAssuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras , Criança , Humanos , Lactente , Austrália/epidemiologia , Nova Zelândia/epidemiologia , Progressão da Doença , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , SobreviventesRESUMO
Mutations in ITM2B cause familial British, Danish, Chinese and Korean dementias. In familial British dementia (FBD) a mutation in the stop codon of the ITM2B gene (also known as BRI2 ) causes a C-terminal cleavage fragment of the ITM2B/BRI2 protein to be extended by 11 amino acids. This fragment, termed amyloid-Bri (ABri), is highly insoluble and forms extracellular plaques in the brain. ABri plaques are accompanied by tau pathology, neuronal cell death and progressive dementia, with striking parallels to the aetiology and pathogenesis of Alzheimer's disease. The molecular mechanisms underpinning FBD are ill-defined. Using patient-derived induced pluripotent stem cells, we show that expression of ITM2B/BRI2 is 34-fold higher in microglia than neurons, and 15-fold higher in microglia compared with astrocytes. This cell-specific enrichment is supported by expression data from both mouse and human brain tissue. ITM2B/BRI2 protein levels are higher in iPSC-microglia compared with neurons and astrocytes. Consequently, the ABri peptide was detected in patient iPSC-derived microglial lysates and conditioned media but was undetectable in patient-derived neurons and control microglia. Pathological examination of post-mortem tissue support ABri expression in microglia that are in proximity to pre-amyloid deposits. Finally, gene co-expression analysis supports a role for ITM2B/BRI2 in disease-associated microglial responses. These data demonstrate that microglia are the major contributors to the production of amyloid forming peptides in FBD, potentially acting as instigators of neurodegeneration. Additionally, these data also suggest ITM2B/BRI2 may be part of a microglial response to disease, motivating further investigations of its role in microglial activation. This has implications for our understanding of the role of microglia and the innate immune response in the pathogenesis of FBD and other neurodegenerative dementias including Alzheimer's disease.
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Background: Pick's disease (PiD) is a rare and predominantly sporadic form of frontotemporal dementia that is classified as a primary tauopathy. PiD is pathologically defined by argyrophilic inclusion Pick bodies and ballooned neurons in the frontal and temporal brain lobes. PiD is characterised by the presence of Pick bodies which are formed from aggregated, hyperphosphorylated, 3-repeat tau proteins, encoded by the MAPT gene. The MAPT H2 haplotype has consistently been associated with a decreased disease risk of the 4-repeat tauopathies of progressive supranuclear palsy and corticobasal degeneration, however its role in susceptibility to PiD is unclear. The primary aim of this study was to evaluate the association between MAPT H2 and risk of PiD. Methods: We established the Pick's disease International Consortium (PIC) and collected 338 (60.7% male) pathologically confirmed PiD brains from 39 sites worldwide. 1,312 neurologically healthy clinical controls were recruited from Mayo Clinic Jacksonville, FL (N=881) or Rochester, MN (N=431). For the primary analysis, subjects were directly genotyped for MAPT H1-H2 haplotype-defining variant rs8070723. In secondary analysis, we genotyped and constructed the six-variant MAPT H1 subhaplotypes (rs1467967, rs242557, rs3785883, rs2471738, rs8070723, and rs7521). Findings: Our primary analysis found that the MAPT H2 haplotype was associated with increased risk of PiD (OR: 1.35, 95% CI: 1.12-1.64 P=0.002). In secondary analysis involving H1 subhaplotypes, a protective association with PiD was observed for the H1f haplotype (0.0% vs. 1.2%, P=0.049), with a similar trend noted for H1b (OR: 0.76, 95% CI: 0.58-1.00, P=0.051). The 4-repeat tauopathy risk haplotype MAPT H1c was not associated with PiD susceptibility (OR: 0.93, 95% CI: 0.70-1.25, P=0.65). Interpretation: The PIC represents the first opportunity to perform relatively large-scale studies to enhance our understanding of the pathobiology of PiD. This study demonstrates that in contrast to its protective role in 4R tauopathies, the MAPT H2 haplotype is associated with an increased risk of PiD. This finding is critical in directing isoform-related therapeutics for tauopathies.
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The advent of clinical trials of disease-modifying agents for neurodegenerative disease highlights the need for evidence-based end point selection. Here we report the longitudinal PROSPECT-M-UK study of progressive supranuclear palsy (PSP), corticobasal syndrome (CBS), multiple system atrophy (MSA) and related disorders, to compare candidate clinical trial end points. In this multicentre UK study, participants were assessed with serial questionnaires, motor examination, neuropsychiatric and MRI assessments at baseline, 6 and 12 months. Participants were classified by diagnosis at baseline and study end, into Richardson syndrome, PSP-subcortical (PSP-parkinsonism and progressive gait freezing subtypes), PSP-cortical (PSP-frontal, PSP-speech and language and PSP-CBS subtypes), MSA-parkinsonism, MSA-cerebellar, CBS with and without evidence of Alzheimer's disease pathology and indeterminate syndromes. We calculated annual rate of change, with linear mixed modelling and sample sizes for clinical trials of disease-modifying agents, according to group and assessment type. Two hundred forty-three people were recruited [117 PSP, 68 CBS, 42 MSA and 16 indeterminate; 138 (56.8%) male; age at recruitment 68.7 ± 8.61 years]. One hundred and fifty-nine completed the 6-month assessment (82 PSP, 27 CBS, 40 MSA and 10 indeterminate) and 153 completed the 12-month assessment (80 PSP, 29 CBS, 35 MSA and nine indeterminate). Questionnaire, motor examination, neuropsychiatric and neuroimaging measures declined in all groups, with differences in longitudinal change between groups. Neuroimaging metrics would enable lower sample sizes to achieve equivalent power for clinical trials than cognitive and functional measures, often achieving N < 100 required for 1-year two-arm trials (with 80% power to detect 50% slowing). However, optimal outcome measures were disease-specific. In conclusion, phenotypic variance within PSP, CBS and MSA is a major challenge to clinical trial design. Our findings provide an evidence base for selection of clinical trial end points, from potential functional, cognitive, clinical or neuroimaging measures of disease progression.
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Atrofia de Múltiplos Sistemas , Transtornos Parkinsonianos , Paralisia Supranuclear Progressiva , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Feminino , Transtornos Parkinsonianos/diagnóstico por imagem , Transtornos Parkinsonianos/tratamento farmacológico , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Paralisia Supranuclear Progressiva/patologia , Atrofia de Múltiplos Sistemas/diagnóstico por imagem , Atrofia de Múltiplos Sistemas/patologia , Imageamento por Ressonância Magnética , Reino UnidoRESUMO
Chromosomal rearrangements involving the KMT2A gene occur frequently in acute lymphoblastic leukaemia (ALL). KMT2A-rearranged ALL (KMT2Ar ALL) has poor long-term survival rates and is the most common ALL subtype in infants less than 1 year of age. KMT2Ar ALL frequently occurs with additional chromosomal abnormalities including disruption of the IKZF1 gene, usually by exon deletion. Typically, KMT2Ar ALL in infants is accompanied by a limited number of cooperative le-sions. Here we report a case of aggressive infant KMT2Ar ALL harbouring additional rare IKZF1 gene fusions. Comprehensive genomic and transcriptomic analyses were performed on sequential samples. This report highlights the genomic complexity of this particular disease and describes the novel gene fusions IKZF1::TUT1 and KDM2A::IKZF1.
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Proteínas F-Box , Leucemia-Linfoma Linfoblástico de Células Precursoras , Lactente , Recém-Nascido , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Fatores de Transcrição/genética , Fusão Gênica , Aberrações Cromossômicas , Genômica , Fator de Transcrição Ikaros/genética , Proteínas F-Box/genética , Histona Desmetilases com o Domínio Jumonji/genéticaRESUMO
BACKGROUND: The recent International Parkinson and Movement Disorder Society diagnostic criteria for multiple system atrophy (MDS-MSA) have been developed to improve diagnostic accuracy although their diagnostic properties have not been evaluated. OBJECTIVES: The aims were to validate the MDS-MSA diagnostic criteria against neuropathological diagnosis and compare their diagnostic performance to previous criteria and diagnosis in clinical practice. METHODS: Consecutive patients with sporadic, progressive, adult-onset parkinsonism, or cerebellar ataxia from the Queen Square Brain Bank between 2009 and 2019 were selected and divided based on neuropathological diagnosis into MSA and non-MSA. Medical records were systematically reviewed, and clinical diagnosis was documented by retrospectively applying the MDS-MSA criteria, second consensus criteria, and diagnosis according to treating clinicians at early (within 3 years of symptom onset) and final stages. Diagnostic parameters (sensitivity, specificity, positive/negative predictive value, and accuracy) were calculated using neuropathological diagnosis as gold standard and compared between different criteria. RESULTS: Three hundred eighteen patients (103 MSA and 215 non-MSA) were included, comprising 248 patients with parkinsonism and 70 with cerebellar ataxia. Clinically probable MDS-MSA showed excellent sensitivity (95.1%), specificity (94.0%), and accuracy (94.3%), although their sensitivity at early stages was modest (62.1%). Clinically probable MDS-MSA outperformed diagnosis by clinicians and by second consensus criteria. Clinically established MDS-MSA showed perfect specificity (100%) even at early stages although to the detriment of low sensitivity. MDS-MSA diagnostic accuracy did not differ according to clinical presentation (ataxia vs. parkinsonism). CONCLUSIONS: MDS-MSA criteria demonstrated excellent diagnostic performance against neuropathological diagnosis and are useful diagnostic tools for clinical practice and research. © 2023 International Parkinson and Movement Disorder Society.
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Ataxia Cerebelar , Atrofia de Múltiplos Sistemas , Doença de Parkinson , Transtornos Parkinsonianos , Adulto , Humanos , Atrofia de Múltiplos Sistemas/patologia , Doença de Parkinson/diagnóstico , Ataxia Cerebelar/diagnóstico , Estudos Retrospectivos , Transtornos Parkinsonianos/diagnóstico , Diagnóstico DiferencialRESUMO
BACKGROUND: Clinical diagnostic accuracy of Parkinson's disease (PD) remains suboptimal. Changes in disease concept may have improved clinical diagnostic accuracy in the past decade. However, current clinical diagnostic criteria have not been validated against neuropathological confirmation. OBJECTIVES: This study aims to provide up-to-date clinical diagnostic accuracy data and validate current clinical diagnostic criteria for PD against neuropathology. METHODS: A retrospective review of medical records of consecutive patients with parkinsonism from the Queen Square Brain Bank was performed between 2009 and 2019. Clinical diagnosis was documented at early (within 5 years of motor symptom onset) and final stages and categorized by movement disorder experts or regular clinicians. Movement Disorder Society Parkinson's disease (MDS-PD) diagnostic criteria were retrospectively applied. Diagnostic accuracy parameters (sensitivity, specificity, positive/negative predictive value, and accuracy) were calculated using neuropathological diagnosis as the gold standard. RESULTS: A total of 267 patients (141 PD and 126 non-PD parkinsonism) were included. Clinical diagnostic accuracy was 97.2% for experts, 92.5% for the MDS clinically probable PD criteria, and 90.3% for clinicians. Similar figures were obtained when applied at an early stage (91.5%, 89.5%, and 84.2% diagnostic accuracy, respectively). MDS clinically established early PD criteria demonstrated very high specificity (98.4%) at early stages. CONCLUSIONS: Our results showed an important improvement in PD clinical diagnostic accuracy in clinical practice over the past decade, more marked at early stages of the disease. MDS-PD diagnostic criteria is a valid tool in clinical practice and research for the identification of PD patients showing excellent sensitivity and specificity, although movement disorder experts' diagnosis remains the gold standard PD diagnosis during life. © 2023 International Parkinson and Movement Disorder Society.
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Doença de Parkinson , Transtornos Parkinsonianos , Humanos , Doença de Parkinson/diagnóstico , Estudos Retrospectivos , Encéfalo , Sensibilidade e EspecificidadeRESUMO
The globular glial tauopathies (GGTs) are a rare group of neurodegenerative diseases with fewer than 90 autopsy-confirmed cases reported in the literature. Although there has been some uncertainty about whether GGT is entirely distinct from progressive supranuclear palsy, a recent study of tau filament structures supports the definition of GGT as a separate neuropathological entity. We present a sporadic case of GGT type II presenting with a progressive corticobasal-primary lateral sclerosis overlap syndrome in a 74-year-old woman. Neuropathological examination identified neuronal and glial tau inclusions, including globular astrocytic and oligodendroglial inclusions. We also discuss the clinical features and molecular pathophysiology of GGT. Increased awareness of this condition could become more important as patients with GGT may be candidates for anti-tau therapies currently undergoing clinical evaluation in patients with other tauopathies.
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Doenças Neurodegenerativas , Paralisia Supranuclear Progressiva , Tauopatias , Feminino , Humanos , Idoso , Proteínas tau , Neuroglia/patologia , Tauopatias/patologiaRESUMO
BACKGROUND: Pediatric acute lymphoblastic leukemia (ALL) therapy is accompanied by treatment-related toxicities (TRTs) and impaired quality of life. In Australia and New Zealand, children with ALL are treated with either Children's Oncology Group (COG) or international Berlin-Frankfurt-Munster (iBFM) Study Group-based therapy. We conducted a prospective registry study to document symptomatic TRTs (venous thrombosis, neurotoxicity, pancreatitis and bone toxicity), compare TRT outcomes to retrospective TRT data, and measure the impact of TRTs on children's general and cancer-related health-related quality of life (HRQoL) and parents' emotional well-being. METHODS: Parents of children with newly diagnosed ALL were invited to participate in the ASSET (Acute Lymphoblastic Leukaemia Subtypes and Side Effects from Treatment) study and a prospective, longitudinal HRQoL study. TRTs were reported prospectively and families completed questionnaires for general (Healthy Utility Index Mark 3) and cancer specific (Pediatric Quality of Life Inventory (PedsQL)-Cancer Module) health related quality of life as well the Emotion Thermometer to assess emotional well-being. RESULTS: Beginning in 2016, 260 pediatric patients with ALL were enrolled on the TRT registry with a median age at diagnosis of 59 months (range 1-213 months), 144 males (55.4%), majority with Pre-B cell immunophenotype, n = 226 (86.9%), 173 patients (66.5%) treated according to COG platform with relatively equal distribution across risk classification sub-groups. From 2018, 79 families participated in the HRQoL study through the first year of treatment. There were 74 TRT recorded, reflecting a 28.5% risk of developing a TRT. Individual TRT incidence was consistent with previous studies, being 7.7% for symptomatic VTE, 11.9% neurotoxicity, 5.4% bone toxicity and 5.0% pancreatitis. Children's HRQoL was significantly lower than population norms throughout the first year of treatment. An improvement in general HRQoL, measured by the HUI3, contrasted with the lack of improvement in cancer-related HRQoL measured by the PedsQL Cancer Module over the first 12 months. There were no persisting differences in the HRQoL impact of COG compared to iBFM therapy. CONCLUSIONS: It is feasible to prospectively monitor TRT incidence and longitudinal HRQoL impacts during ALL therapy. Early phases of ALL therapy, regardless of treatment platform, result in prolonged reductions in cancer-related HRQoL.
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Pancreatite , Leucemia-Linfoma Linfoblástico de Células Precursoras , Doença Aguda , Criança , Humanos , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Qualidade de Vida , Estudos Retrospectivos , Inquéritos e QuestionáriosRESUMO
Parkinson's disease (PD) is the most common movement disorder, with resting tremor, rigidity, bradykinesia and postural instability being major symptoms1. Neuropathologically, it is characterized by the presence of abundant filamentous inclusions of α-synuclein in the form of Lewy bodies and Lewy neurites in some brain cells, including dopaminergic nerve cells of the substantia nigra2. PD is increasingly recognised as a multisystem disorder, with cognitive decline being one of its most common non-motor symptoms. Many patients with PD develop dementia more than 10 years after diagnosis3. PD dementia (PDD) is clinically and neuropathologically similar to dementia with Lewy bodies (DLB), which is diagnosed when cognitive impairment precedes parkinsonian motor signs or begins within one year from their onset4. In PDD, cognitive impairment develops in the setting of well-established PD. Besides PD and DLB, multiple system atrophy (MSA) is the third major synucleinopathy5. It is characterized by the presence of abundant filamentous α-synuclein inclusions in brain cells, especially oligodendrocytes (Papp-Lantos bodies). We previously reported the electron cryo-microscopy structures of two types of α-synuclein filament extracted from the brains of individuals with MSA6. Each filament type is made of two different protofilaments. Here we report that the cryo-electron microscopy structures of α-synuclein filaments from the brains of individuals with PD, PDD and DLB are made of a single protofilament (Lewy fold) that is markedly different from the protofilaments of MSA. These findings establish the existence of distinct molecular conformers of assembled α-synuclein in neurodegenerative disease.
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Química Encefálica , Encéfalo , Microscopia Crioeletrônica , Doença por Corpos de Lewy , alfa-Sinucleína , Humanos , alfa-Sinucleína/química , alfa-Sinucleína/metabolismo , alfa-Sinucleína/ultraestrutura , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/ultraestrutura , Doença por Corpos de Lewy/patologia , Doença de Parkinson/complicações , Doença de Parkinson/patologia , Demência/complicações , Demência/patologiaRESUMO
BACKGROUND: The molecular drivers of early sporadic Parkinson's disease (PD) remain unclear, and the presence of widespread end stage pathology in late disease masks the distinction between primary or causal disease-specific events and late secondary consequences in stressed or dying cells. However, early and mid-stage Parkinson's brains (Braak stages 3 and 4) exhibit alpha-synuclein inclusions and neuronal loss along a regional gradient of severity, from unaffected-mild-moderate-severe. Here, we exploited this spatial pathological gradient to investigate the molecular drivers of sporadic PD. METHODS: We combined high precision tissue sampling with unbiased large-scale profiling of protein expression across 9 brain regions in Braak stage 3 and 4 PD brains, and controls, and verified these results using targeted proteomic and functional analyses. RESULTS: We demonstrate that the spatio-temporal pathology gradient in early-mid PD brains is mirrored by a biochemical gradient of a changing proteome. Importantly, we identify two key events that occur early in the disease, prior to the occurrence of alpha-synuclein inclusions and neuronal loss: (i) a metabolic switch in the utilisation of energy substrates and energy production in the brain, and (ii) perturbation of the mitochondrial redox state. These changes may contribute to the regional vulnerability of developing alpha-synuclein pathology. Later in the disease, mitochondrial function is affected more severely, whilst mitochondrial metabolism, fatty acid oxidation, and mitochondrial respiration are affected across all brain regions. CONCLUSIONS: Our study provides an in-depth regional profile of the proteome at different stages of PD, and highlights that mitochondrial dysfunction is detectable prior to neuronal loss, and alpha-synuclein fibril deposition, suggesting that mitochondrial dysfunction is one of the key drivers of early disease.
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Doença de Parkinson , alfa-Sinucleína , Humanos , Mitocôndrias/metabolismo , Doença de Parkinson/patologia , Proteoma/metabolismo , Proteômica , alfa-Sinucleína/metabolismoRESUMO
Neuropathologic criteria for progressive supranuclear palsy (PSP) proposed by a National Institute of Neurological Disorders and Stroke (NINDS) working group were published in 1994 and based on the presence of neurofibrillary tangles in basal ganglia and brainstem. These criteria did not stipulate detection methods or incorporate glial tau pathology. In this study, a group of 14 expert neuropathologists scored digital slides from 10 brain regions stained with hematoxylin and eosin (H&E) and phosphorylated tau (AT8) immunohistochemistry. The cases included 15 typical and atypical PSP cases and 10 other tauopathies. Blinded to clinical and neuropathological information, raters provided a categorical diagnosis (PSP or not-PSP) based upon provisional criteria that required neurofibrillary tangles or pretangles in two of three regions (substantia nigra, subthalamic nucleus, globus pallidus) and tufted astrocytes in one of two regions (peri-Rolandic cortices, putamen). The criteria showed high sensitivity (0.97) and specificity (0.91), as well as almost perfect inter-rater reliability for diagnosing PSP and differentiating it from other tauopathies (Fleiss kappa 0.826). Most cases (17/25) had 100% agreement across all 14 raters. The Rainwater Charitable Foundation criteria for the neuropathologic diagnosis of PSP feature a simplified diagnostic algorithm based on phosphorylated tau immunohistochemistry and incorporate tufted astrocytes as an essential diagnostic feature.
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Paralisia Supranuclear Progressiva , Tauopatias , Humanos , Emaranhados Neurofibrilares/patologia , Neuropatologia , Reprodutibilidade dos Testes , Paralisia Supranuclear Progressiva/diagnóstico , Paralisia Supranuclear Progressiva/patologia , Tauopatias/diagnóstico , Tauopatias/patologia , Proteínas tauRESUMO
Porcine circovirus type 3 (PCV3) is an emerging pathogen that has been reported worldwide in all ages of healthy and clinically ill pigs. The presence of this virus in Hungary has been confirmed in a commercial farm experiencing reproductive failures, but there were no data on the circulation of PCV3 in the country. Here we report the prevalence and the genetic diversity of PCV3 in Hungarian herds. To estimate the prevalence, 1855 serum samples, 176 oral fluid and 97 processing fluid samples were collected in a systematic, cross-sectional method from 20 large scale swineherds and tested by real-time qPCR. PCV3 was present in at least one type of diagnostic matrix in 19 out of the 20 (95%) pig farms. The highest detection rates were observed in the processing fluid samples (61%), but 41% of the oral fluid and 23% of the serum samples were positive. The virus was found in all age groups, and slightly more adult animals were infected than growing pigs, but the viral burden was lower amongst them. Phylogenetic analysis of nine complete genomes, obtained from either the sampled herds or organ samples of PCV3-positive carcasses, showed high nucleotide identity between the detected sequences, which all belonged to the PCV3a genotype. Our results indicate that PCV3 is widespread in Hungary, but in most cases, the virus seems to circulate subclinically, infecting all age groups and production phases without the presence of apparent clinical disease.
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Infecções por Circoviridae , Circovirus , Doenças dos Suínos , Animais , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/veterinária , Circovirus/genética , Estudos Transversais , Hungria/epidemiologia , Filogenia , Prevalência , Suínos , Doenças dos Suínos/epidemiologiaRESUMO
Children with neurofibromatosis have a higher risk of developing juvenile myelomonocytic leukemia and acute myeloid leukemia, but rarely develop B-cell acute lymphoblastic leukemia (B-ALL). Through in-vitro modeling, a novel NF1 p.L2467 frameshift (fs) mutation identified in a relapsed/refractory Ph-like B-ALL patient with neurofibromatosis demonstrated cytokine independence and increased RAS signaling, indicative of leukemic transformation. Furthermore, these cells were sensitive to the MEK inhibitors trametinib and mirdametinib. Bi-allelic NF1 loss of function may be a contributing factor to relapse and with sensitivity to MEK inhibitors, suggests a novel precision medicine target in the setting of neurofibromatosis patients with B-ALL.