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13 Pág. Centro de Investigación en Sanidad Animal (CISA), More than 40 pathogenic heterozygous PRNP mutations causing inherited prion diseases have been identified to date. Recessive inherited prion disease has not been described to date., This work was funded by the Instituto de Salud Carlos III (grant no. PI20/00448 to RSV), Spanish Ministerio de Ciencia e Innovación (grant no. PDI2019-105837RB-I00 to J.M.T. and J.C.E., and RTI2018-098515-B-I00 to J.C.), Fundació La Marató de TV3 (grant no. 201821-31 to J.C.E.), Instituto Nacional de Investigación y Tecnología Agraria y Agroalimentaria (fellowship INIA-FPI-SGIT-2015-02 to A.M.M.) and Dr Baselga funds for CJD research. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

BACKGROUND The influence of concomitant brain pathologies on the progression rate in PSP is unclear. OBJECTIVES To analyze the frequency and severity of copathologies and their impact on the progression in PSP. METHODS We analyzed clinic-pathological features of 101 PSP patients. Diagnoses and stages of copathologies were established according to standardized criteria, including Alzheimer's disease-related pathology, argyrophilic grains, Lewy-related pathology, transactive response DNA-binding protein 43 pathology, fused in sarcoma pathology, cerebral amyloid angiopathy, and small vessel disease. Demographic data and major clinical milestones (frequency and latency to onset) were extracted from patients' files. RESULTS Only 8% of 101 patients presented with pure PSP pathology without any copathology. Alzheimer's disease-related pathology was the most frequent (84%), followed by argyrophilic grains (58%), both occurring as single copathology or in combination with other proteinopathies or cerebrovascular disease. Lewy-related and transactive response DNA-binding protein 43 copathology occurred rarely (8% and 6%, respectively). Fused in sarcoma-positive cases were not found. While being common, copathology was mostly mild in severity, with the exception of frequently widespread argyrophilic grains. Small vessel disease was also frequent (65%). Cerebral amyloid angiopathy occurred only in the presence of Alzheimer's disease-related changes (25%). The copathologies did not have major impact on prevalence and time frame of major disease milestones. CONCLUSIONS In PSP, concomitant neurodegenerative proteinopathies or cerebrovascular diseases are frequent, but generally mild in severity. Our data confirmed that four repeat tau is still the most relevant target for PSP, whereas the impact of copathologies on progression rate appears to be of less importance. This is relevant information for the development of disease-modifying therapies. © 2020 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

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[No abstract available]

Genetic discoveries of Alzheimer’s disease are the drivers of our understanding, and together with polygenetic risk stratification can contribute towards planning of feasible and efficient preventive and curative clinical trials. We first perform a large genetic association study by merging all available case-control datasets and by-proxy study results (discovery n = 409,435 and validation size n = 58,190). Here, we add six variants associated with Alzheimer’s disease risk (near APP, CHRNE, PRKD3/NDUFAF7, PLCG2 and two exonic variants in the SHARPIN gene). Assessment of the polygenic risk score and stratifying by APOE reveal a 4 to 5.5 years difference in median age at onset of Alzheimer’s disease patients in APOE ɛ4 carriers. Because of this study, the underlying mechanisms of APP can be studied to refine the amyloid cascade and the polygenic risk score provides a tool to select individuals at high risk of Alzheimer’s disease. © 2021, The Author(s).

We present the clinical and neuropathological findings of a patient with early onset Alzheimer's dementia (AD), heterozygous carrier of the rare Apolipoprotein E Christchurch (APOEch) variant. The patient did not harbor any pathogenic mutation in known Mendelian genes related to AD or other neurodegenerative disorders. A sibling of this patient, also carrying the APOEch variant, developed AD at the age of 66 years old. Our data suggest a possible deleterious effect of this variant, which contrast with the protective role that has been previously shown in a subject homozygous for the APOEch with he Paisa PSEN1 mutation.

Background: The Movement Disorder Society diagnostic criteria for progressive supranuclear palsy introduced the diagnostic certainty level “suggestive of progressive supranuclear palsy” for clinical conditions with subtle signs, suggestive of the disease. This category aims at the early identification of patients, in whom the diagnosis may be confirmed as the disease evolves. Objective: To assess the diagnostic performance of the defined clinical conditions suggestive of progressive supranuclear palsy in an autopsy-confirmed cohort. Methods: Diagnostic performance of the criteria was analyzed based on retrospective clinical data of 204 autopsy-confirmed patients with progressive supranuclear palsy and 216 patients with other neurological diseases. Results: The conditions suggestive of progressive supranuclear palsy strongly increased the sensitivity compared to the National Institute of Neurological Disorders and Stroke and Society for Progressive Supranuclear Palsy criteria. Within the first year after symptom onset, 40% of patients with definite progressive supranuclear palsy fulfilled criteria for suggestive of progressive supranuclear palsy. Two-thirds of patients suggestive of progressive supranuclear palsy evolved into probable progressive supranuclear palsy after an average of 3.6 years. Application of the criteria for suggestive of progressive supranuclear palsy reduced the average time to diagnosis from 3.8 to 2.2 years. Conclusions: Clinical conditions suggestive of progressive supranuclear palsy allow earlier identification of patients likely to evolve into clinically possible or probable progressive supranuclear and to have underlying progressive supranuclear palsy pathology. Further work needs to establish the specificity and positive predictive value of this category in real-life clinical settings, and to develop specific biomarkers that enhance their diagnostic accuracy in early disease stages. © 2020 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society. © 2020 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society

Abnormal cytoplasmic accumulation of fused in sarcoma (FUS) protein is the pathological hallmark of some cases of amyotrophic lateral sclerosis (ALS) with transactive response DNA‐binding protein of 43KDa (TDP‐43)‐negative pathology that lack SOD1 mutations. FUS is an RNA‐binding protein located predominantly in the nucleus and is involved in regulation of transcription, alternative splicing, RNA stability, microRNA biogenesis, apoptosis and cell division. FUS, Ewing's sarcoma (EWS) and TATA‐binding protein‐associated factor 15 (TAF15) proteins constitute the FET (FUS/EWS/TAF15) family, highly conserved and ubiquitously expressed RNA‐binding proteins that shuttle between nucleus and cytoplasm assisted by the nuclear import protein Transportin 1 (Trn1), This study was partially funded by Fundació Marató de TV3 (grant no. 20143810 to RSV, no. 20141610 to EG and no. 201437.10 to RRG) and Fondo Europeo de Desarrollo Regional (FEDER) (PI16/01673 to JG and PI15/01618 to RRG).

Background: The Movement Disorder Society criteria for progressive supranuclear palsy define diagnostic allocations, stratified by certainty levels and clinical predominance types. We aimed to study the frequency of ambiguous multiple allocations and to develop rules to eliminate them. Methods: We retrospectively collected standardized clinical data by chart review in a multicenter cohort of autopsy-confirmed patients with progressive supranuclear palsy, to classify them by diagnostic certainty level and predominance type and to identify multiple allocations. Results: Comprehensive data were available from 195 patients. More than one diagnostic allocation occurred in 157 patients (80.5%). On average, 5.4 allocations were possible per patient. We developed four rules for Multiple Allocations eXtinction (MAX). They reduced the number of patients with multiple allocations to 22 (11.3%), and the allocations per patient to 1.1. Conclusions: The proposed MAX rules help to standardize the application of the Movement Disorder Society criteria for progressive supranuclear palsy. © 2019 International Parkinson and Movement Disorder Society. © 2019 International Parkinson and Movement Disorder Society

Soluble amyloid-beta (A beta) is considered to be a critical component in the pathogenesis of Alzheimer's disease (AD). Evidence suggests that these non-fibrillar A beta assemblies are implicated in synaptic dysfunction, neurodegeneration and cell death. However, characterization of these species comes mainly from studies in cellular or animal models, and there is little data in intact human samples due to the lack of adequate optical microscopic resolution to study these small structures. Here, to achieve super-resolution in all three dimensions, we applied Array Tomography (AT) and Stimulated Emission Depletion microscopy (STED), to characterize in postmortem human brain tissue non-fibrillar A beta structures in amyloid plaques of cases with autosomal dominant and sporadic AD. Ultrathin sections scanned with super-resolution STED microscopy allowed the detection of small A beta structures of the order of 100 nm. We reconstructed a whole human amyloid plaque and established that plaques are formed by a dense core of higher order A beta species (similar to 0.022 mu m(3)) and a peripheral halo of smaller A beta structures (similar to 0.003 mu m(3)). This work highlights the potential of AT-STED for human neuropathological studies.

Background: PSP is a neuropathologically defined disease entity. Clinical diagnostic criteria, published in 1996 by the National Institute of Neurological Disorders and Stroke/Society for PSP, have excellent specificity, but their sensitivity is limited for variant PSP syndromes with presentations other than Richardson's syndrome. Objective: We aimed to provide an evidence- and consensus-based revision of the clinical diagnostic criteria for PSP. Methods: We searched the PubMed, Cochrane, Medline, and PSYCInfo databases for articles published in English since 1996, using postmortem diagnosis or highly specific clinical criteria as the diagnostic standard. Second, we generated retrospective standardized clinical data from patients with autopsy-confirmed PSP and control diseases. On this basis, diagnostic criteria were drafted, optimized in two modified Delphi evaluations, submitted to structured discussions with consensus procedures during a 2-day meeting, and refined in three further Delphi rounds. Results: Defined clinical, imaging, laboratory, and genetic findings serve as mandatory basic features, mandatory exclusion criteria, or context-dependent exclusion criteria. We identified four functional domains (ocular motor dysfunction, postural instability, akinesia, and cognitive dysfunction) as clinical predictors of PSP. Within each of these domains, we propose three clinical features that contribute different levels of diagnostic certainty. Specific combinations of these features define the diagnostic criteria, stratified by three degrees of diagnostic certainty (probable PSP, possible PSP, and suggestive of PSP). Clinical clues and imaging findings represent supportive features. Conclusions: Here, we present new criteria aimed to optimize early, sensitive, and specific clinical diagnosis of PSP on the basis of currently available evidence. © 2017 International Parkinson and Movement Disorder Society. © 2017 International Parkinson and Movement Disorder Society

Synaptic loss occurs early in dementia with Lewy bodies (DLB), but its relationship to alpha-synuclein pathology remains unclear. Using array tomography microscopy, Colom-Cadena et al. reveal small phosphorylated alpha-synuclein aggregates at synaptic terminals of DLB cases, supporting a direct association between alpha-synuclein accumulation and synaptic dysfunction.Dementia with Lewy bodies is characterized by the accumulation of Lewy bodies and Lewy neurites in the CNS, both of which are composed mainly of aggregated alpha-synuclein phosphorylated at Ser129. Although phosphorylated alpha-synuclein is believed to exert toxic effects at the synapse in dementia with Lewy bodies and other alpha-synucleinopathies, direct evidence for the precise synaptic localization has been difficult to achieve due to the lack of adequate optical microscopic resolution to study human synapses. In the present study we applied array tomography, a microscopy technique that combines ultrathin sectioning of tissue with immunofluorescence allowing precise identification of small structures, to quantitatively investigate the synaptic phosphorylated alpha-synuclein pathology in dementia with Lewy bodies. We performed array tomography on human brain samples from five patients with dementia with Lewy bodies, five patients with Alzheimer's disease and five healthy control subjects to analyse the presence of phosphorylated alpha-synuclein immunoreactivity at the synapse and their relationship with synapse size. Main analyses were performed in blocks from cingulate cortex and confirmed in blocks from the striatum of cases with dementia with Lewy bodies. A total of 1 318 700 single pre- or postsynaptic terminals were analysed. We found that phosphorylated alpha-synuclein is present exclusively in dementia with Lewy bodies cases, where it can be identified in the form of Lewy bodies, Lewy neurites and small aggregates (< 0.16 A mu m(3)). Between 19% and 25% of phosphorylated alpha-synuclein deposits were found in presynaptic terminals mainly in the form of small aggregates. Synaptic terminals that co-localized with small aggregates of phosphorylated alpha-synuclein were significantly larger than those that did not. Finally, a gradient of phosphorylated alpha-synuclein aggregation in synapses (pre > pre + post > postsynaptic) was observed. These results indicate that phosphorylated alpha-synuclein is found at the presynaptic terminals of dementia with Lewy bodies cases mainly in the form of small phosphorylated alpha-synuclein aggregates that are associated with changes in synaptic morphology. Overall, our data support the notion that pathological phosphorylated alpha-synuclein may disrupt the structure and function of the synapse in dementia with Lewy bodies.

Background: Progressive supranuclear palsy (PSP) is a neuropathologically defined disease presenting with a broad spectrum of clinical phenotypes. Objective: To identify clinical features and investigations that predict or exclude PSP pathology during life, aiming at an optimization of the clinical diagnostic criteria for PSP. Methods: We performed a systematic review of the literature published since 1996 to identify clinical features and investigations that may predict or exclude PSP pathology. We then extracted standardized data from clinical charts of patients with pathologically diagnosed PSP and relevant disease controls and calculated the sensitivity, specificity, and positive predictive value of key clinical features for PSP in this cohort. Results: Of 4166 articles identified by the database inquiry, 269 met predefined standards. The literature review identified clinical features predictive of PSP, including features of the following 4 functional domains: ocular motor dysfunction, postural instability, akinesia, and cognitive dysfunction. No biomarker or genetic feature was found reliably validated to predict definite PSP. High-quality original natural history data were available from 206 patients with pathologically diagnosed PSP and from 231 pathologically diagnosed disease controls (54 corticobasal degeneration, 51 multiple system atrophy with predominant parkinsonism, 53 Parkinson's disease, 73 behavioral variant frontotemporal dementia). We identified clinical features that predicted PSP pathology, including phenotypes other than Richardson's syndrome, with varying sensitivity and specificity. Conclusions: Our results highlight the clinical variability of PSP and the high prevalence of phenotypes other than Richardson's syndrome. The features of variant phenotypes with high specificity and sensitivity should serve to optimize clinical diagnosis of PSP. © 2017 International Parkinson and Movement Disorder Society. © 2017 International Parkinson and Movement Disorder Society

Premature termination codon (PTC) mutations in the ATP-Binding Cassette, Sub-Family A, Member 7 gene (ABCA7) have recently been identified as intermediate-to-high penetrant risk factor for late-onset Alzheimer’s disease (LOAD). High variability, however, is observed in downstream ABCA7 mRNA and protein expression, disease penetrance, and onset age, indicative of unknown modifying factors. Here, we investigated the prevalence and disease penetrance of ABCA7 PTC mutations in a large early onset AD (EOAD)—control cohort, and examined the effect on transcript level with comprehensive third-generation long-read sequencing. We characterized the ABCA7 coding sequence with next-generation sequencing in 928 EOAD patients and 980 matched control individuals. With MetaSKAT rare variant association analysis, we observed a fivefold enrichment (p = 0.0004) of PTC mutations in EOAD patients (3%) versus controls (0.6%). Ten novel PTC mutations were only observed in patients, and PTC mutation carriers in general had an increased familial AD load. In addition, we observed nominal risk reducing trends for three common coding variants. Seven PTC mutations were further analyzed using targeted long-read cDNA sequencing on an Oxford Nanopore MinION platform. PTC-containing transcripts for each investigated PTC mutation were observed at varying proportion (5–41% of the total read count), implying incomplete nonsense-mediated mRNA decay (NMD). Furthermore, we distinguished and phased several previously unknown alternative splicing events (up to 30% of transcripts). In conjunction with PTC mutations, several of these novel ABCA7 isoforms have the potential to rescue deleterious PTC effects. In conclusion, ABCA7 PTC mutations play a substantial role in EOAD, warranting genetic screening of ABCA7 in genetically unexplained patients. Long-read cDNA sequencing revealed both varying degrees of NMD and transcript-modifying events, which may influence ABCA7 dosage, disease severity, and may create opportunities for therapeutic interventions in AD. © 2017, The Author(s).

The BrainNet Europe consortium assessed the reproducibility in the assignment of the type of frontotemporal lobar degeneration (FTLD) with TAR DNA-binding protein (TDP) 43 following current recommendations. The agreement rates were influenced by the immunohistochemical (IHC) method and by the classification strategy followed. p62-IHC staining yielded good uniform quality of stains, but the most reliable results were obtained implementing specific Abs directed against the hallmark protein TDP43. Both assessment of the type and the extent of lesions were influenced by the Abs and by the quality of stain. Assessment of the extent of the lesions yielded poor results repeatedly; thus, the extent of pathology should not be used in diagnostic consensus criteria. Whilst 31 neuropathologists typed 30 FTLD-TDP cases, inter-rater agreement ranged from 19 to 100 per cent, being highest when applying phosphorylated TDP43/IHC. The agreement was highest when designating Type C or Type A/B. In contrast, there was a poor agreement when attempting to separate Type A or Type B FTLD-TDP. In conclusion, we can expect that neuropathologist, independent of his/her familiarity with FTLD-TDP pathology, can identify a TDP43-positive FTLD case. The goal should be to state a Type (A, B, C, D) or a mixture of Types (A/B, A/C or B/C). Neuropathologists, other clinicians and researchers should be aware of the pitfalls whilst doing so. Agreement can be reached in an inter-laboratory setting regarding Type C cases with thick and long neurites, whereas the differentiation between Types A and B may be more troublesome. © 2014, Springer-Verlag Wien.

Here, we summarise the results after carrying out a large survey regarding the assessment of vascular alterations, both vessel changes and vascular lesions in an inter-laboratory setting. In total, 32 neuropathologists from 22 centres, most being members of BrainNet Europe (BNE), participated by filling out a questionnaire with emphasis on assessment of common vascular alterations seen in the brains of aged subjects. A certain level of harmonisation has been reached among BNE members regarding sectioning of the brain, harvesting of brain tissue for histology and staining used when compared to the survey carried out in 2006 by Pantoni and colleagues. The most significant variability was seen regarding the assessment of severity and of clinical significance of vascular alterations. Two strategies have recently been recommended regarding the assessment of vascular alterations in aged and demented subjects. The National Institute on Aging - Alzheimer's Association (NIA-AA) recommends the assessment of hippocampal sclerosis, vascular brain injury and microvascular lesions in 12 regions. Although this strategy will be easy to follow, the recommendations do not inform how the load of observed alterations should be assessed and when the observed lesions are of significance. Deramecourt and his colleagues recommend an assessment and semiquantitative grading of various pathologies in 4 brain regions. This strategy yielded a total score of 0 to 20 as an estimate of pathology load. It is, however, not clear which score is considered to be of clinical significance. Furthermore, in several BNE trials the semiquantitative assessment has yielded poor agreement rates; an observation that might negatively influence the strategy proposed by Deramecourt and his colleagues. In line with NIA-AA, a dichotomised approach of easily recognisable lesions in a standardised set of brain regions harvested for neuropathological assessment and applying reproducible sampling and staining strategies is recommended by BNE. However, a simple strategy regarding assessment of load of alteration is urgently needed to yield reproducible, and at the same time, comparable results between centres.

The phenotypic variability of progressive supranuclear palsy (PSP) may account for its frequent misdiagnosis, in particular in early stages of the disease. However, large multicenter studies to define the frequency and natural history of PSP phenotypes are missing. In a cohort of 100 autopsy-confirmed patients we studied the phenotypic spectrum of PSP by retrospective chart review. Patients were derived from five brain banks with expertise in neurodegenerative disorders with referrals from multiple academic hospitals. The clinical characteristics of the 100 cases showed remarkable heterogeneity. Most strikingly, only 24% of cases presented as Richardson's Syndrome (RS), and more than half of the cases either showed overlapping features of several predescribed phenotypes, or features not fitting proposed classification criteria for PSP phenotypes. Classification of patients according to predominant clinical features in the first 2 years of the disease course allowed a more comprehensive description of the phenotypic spectrum. These predominance types differed significantly with regard to survival time and frequency of cognitive deficits. In summary, the phenotypic spectrum of PSP may be broader and more variable than previously described in single-center studies. Thus, too strict clinical criteria defining distinct phenotypes may not reflect this variability. A more pragmatic clinical approach using predominance types could potentially be more helpful in the early recognition of and for making prognostic predictions for these patients. Given the limitations arising from the retrospective nature of this analysis, a systematic validation in a prospective cohort study is imperative. © 2014 International Parkinson and Movement Disorder Society.

The phenotypic variability of progressive supranuclear palsy (PSP) may account for its frequent misdiagnosis, in particular in early stages of the disease. However, large multicenter studies to define the frequency and natural history of PSP phenotypes are missing. In a cohort of 100 auto-psyconfirmed patients we studied the phenotypic spectrum of PSP by retrospective chart review. Patients were derived from five brain banks with expertise in neurodegenerative disorders with referrals from multiple academic hospitals. The clinical characteristics of the 100 cases showed remarkable heterogeneity. Most strikingly, only 24% of cases presented as Richardson's Syndrome (RS), and more than half of the cases either showed overlapping features of several predescribed phenotypes, or features not fitting proposed classification criteria for PSP phenotypes. Classification of patients according to predominant clinical features in the first 2 years of the disease course allowed a more comprehensive description of the phenotypic spectrum. These predominance types differed significantly with regard to survival time and frequency of cognitive deficits. In summary, the phenotypic spectrum of PSP may be broader and more variable than previously described in single-center studies. Thus, too strict clinical criteria defining distinct phenotypes may not reflect this variability. A more pragmatic clinical approach using predominance types could potentially be more helpful in the early recognition of and for making prognostic predictions for these patients. Given the limitations arising from the retrospective nature of this analysis, a systematic validation in a prospective cohort study is imperative. (C) 2014 International Parkinson and Movement Disorder Society

To determine the reliability of assessment of alpha-synuclein-immunoreactive (alphaS-IR) structures by neuropathologists, 28 evaluators from 17 centers of BrainNet Europe examined current methods and reproducibility of alphaS-IR evaluation using a tissue microarray (TMA) technique. Tissue microarray blocks were constructed of samples from the participating centers that contained alphaS-IR structures. Slides from these blocks were stained in each center and assessed for neuronal perikaryal inclusions, neurites, and glial cytoplasmic inclusions. The study was performed in 2 phases. First, the TMA slides were stained with the antibody of the center's choice. In this phase, 59% of the sections were of good or acceptable quality, and 4 of 9 antibodies used performed consistently. Differences in interpretation and categorization of alphaS-IR structures, however, led to differing results between the laboratories. Prior to the second phase, the neuropathologists participated in a training session on the evaluation of alphaS-IR structures. Based on the results of the first phase, selected antibodies using designated antigen retrieval methods were then applied to TMA slides in the second phase. When the designated methods of both staining and evaluation were applied, all 26 subsequently stained TMA sections evaluated were of good/acceptable quality, and a high level of concordance in the assessment of the presence or absence of specific alphaS-IR structures was achieved. A semiquantitative assessment of alphaS-IR neuronal perikaryal inclusions yielded agreements ranging from 49% to 82%, with best concordance in cortical core samples. These results suggest that rigorous methodology and dichotomized assessment (i.e. determining the presence or absence of alphaS-IR) should be applied, and that semiquantitative assessment can be recommended only for the cortical samples. Moreover, the study demonstrates that there are limitations in the scoring of alphaS-IR structures.

The microtubule-associated protein tau (MAPT) H1 haplotype has been identified as a genetic risk factor for synucleinopathies. However, whether it modulates tau or a-synuclein pathology remains unknown. Our aim was to investigate the relationship between MAPT haplotypes and pathologic aggregates of tau and a-synuclein in pathologically confirmed cases of dementia with Lewy bodies (DLB). Twenty-two cases fulfilling clinical and neuropathological criteria for DLB were included. Clinical and neuropathological data were collected, and APOE and MAPT genotypes were determined. Tau and a-synuclein pathology was assessed semiquantitatively in 17 brain areas and total scores were calculated. DLB H1/H1 (n = 12) and H2 carriers (n = 10) did not differ in demographics, clinical variables, concomitant Alzheimer's pathology, or APOE genotype. Total a-synuclein scores were significantly increased in the H1/H1 group (p = 0.011), largely due to an increase in brainstem regions. This difference was driven by an increase in Lewy bodies and diffuse and punctuate cytoplasmatic a-synuclein aggregates (p = 0.007 and p = 0.025 respectively). These findings provide a mechanistic link for the genetic association between MAPT haplotypes and synucleinopathies. © 2013 Elsevier Inc.

Dementia with Lewy bodies (DLB) is pathologically characterized by alpha-synuclein aggregates in the brain. Most patients with DLB also show cerebral Alzheimer disease-type pathology (i.e. beta-amyloid plaques and hyperphosphorylated tau deposits). It is unclear whether this overlap is coincidental or driven by specific regional or cellular interactions. The aims of this study were to investigate the regional convergence of alpha-synuclein, tau, and beta-amyloid and to identify patterns of cellular co-occurrence of tau and alpha-synuclein in DLB. The study group consisted of 22 patients who met clinical and neuropathologic criteria for DLB. Protein aggregates were assessed semiquantitatively in 17 brain areas. APOE and MAPT genotypes were determined. Cellular co-occurrence of tau and alpha-synuclein was evaluated by double immunofluorescence. We found that total beta-amyloid pathology scores correlated positively with total alpha-synuclein pathology scores (rho = 0.692, p = 0.001). The factors that correlated best with the amount of alpha-synuclein pathology were the severity of beta-amyloid pathology and presence of the MAPT H1 haplotype. Tau and alpha-synuclein frequently colocalized in limbic areas, but no correlation between total pathology scores was observed. This study confirms and extends the role of beta-amyloid deposition and the MAPT H1 haplotype as contributing factors in DLB pathogenesis and demonstrates the confluence of multiple agents in neurodegenerative diseases.

Multiple system atrophy (MSA) is a sporadic alpha-synucleinopathy clinically characterized by variable degrees of parkinsonism, cerebellar ataxia and autonomic dysfunction. The histopathological hallmark of MSA is glial cytoplasmic inclusion (GCI). It is considered to represent the earliest stage of the degenerative process in MSA and to precede neuronal degeneration. Sporadic Creutzfeldt-Jakob disease (sCJD) is a fatal, rapidly progressive dementia generally associated with ataxia, pyramidal and extrapyramidal symptoms and myoclonus. Definite diagnosis needs neuropathological demonstration of variable degrees of spongiform degeneration of neuropil, neuronal loss, astro- and microgliosis, and the presence of abnormal deposits of the misfolded prion protein PrPres. Both diseases, CJD and MSA are infrequent among neurodegenerative diseases. In the present report we describe clinical and neuropathological findings of a previously healthy 64-year-old woman who developed symptoms of classical CJD. At post mortem examination, the brain showed in addition to classical methionine/methionine PrPres type 1 (MM1) sCJD changes and moderate Alzheimer-type pathology, features of preclinical MSA with minimal histopathological changes. These were characterized by discrete amounts of alpha-synuclein immunoreacive glial cytoplasmic inclusions in the striato-nigral system, isolated intraneuronal inclusions in pigmented neurons of the substantia nigra, as well as some vermiform intranuclear inclusions. To our knowledge, this is the first report on the coexistence of definite sCJD and minimal changes MSA in the same patient.

Here, we summarise the results after carrying out a large survey regarding the assessment of vascular alterations, both vessel changes and vascular lesions in an inter-laboratory setting. In total, 32 neuropathologists from 22 centres, most being members of BrainNet Europe (BNE), participated by filling out a questionnaire with emphasis on assessment of common vascular alterations seen in the brains of aged subjects. A certain level of harmonisation has been reached among BNE members regarding sectioning of the brain, harvesting of brain tissue for histology and staining used when compared to the survey carried out in 2006 by Pantoni and colleagues. The most significant variability was seen regarding the assessment of severity and of clinical significance of vascular alterations. Two strategies have recently been recommended regarding the assessment of vascular alterations in aged and demented subjects. The National Institute on Aging - Alzheimer's Association (NIA-AA) recommends the assessment of hippocampal sclerosis, vascular brain injury and microvascular lesions in 12 regions. Although this strategy will be easy to follow, the recommendations do not inform how the load of observed alterations should be assessed and when the observed lesions are of significance. Deramecourt and his colleagues recommend an assessment and semiquantitative grading of various pathologies in 4 brain regions. This strategy yielded a total score of 0 to 20 as an estimate of pathology load. It is, however, not clear which score is considered to be of clinical significance. Furthermore, in several BNE trials the semiquantitative assessment has yielded poor agreement rates; an observation that might negatively influence the strategy proposed by Deramecourt and his colleagues. In line with NIA-AA, a dichotomised approach of easily recognisable lesions in a standardised set of brain regions harvested for neuropathological assessment and applying reproducible sampling and staining strategies is recommended by BNE. However, a simple strategy regarding assessment of load of alteration is urgently needed to yield reproducible, and at the same time, comparable results between centres. © 2012 Elsevier Inc.

When 22 members of the BrainNet Europe (BNE) consortium assessed 31 cases with α-synuclein (αS) immunoreactive (IR) pathology applying the consensus protocol described by McKeith and colleagues in 2005, the inter-observer agreement was 80%, being lowest in the limbic category (73%). When applying the staging protocol described by Braak and colleagues in 2003, agreement was only 65%, and in some cases as low as 36%. When modifications of these strategies, i.e., McKeith's protocol by Leverenz and colleagues from 2009, Braak's staging by Müller and colleagues from 2005 were applied then the agreement increased to 78 and 82%, respectively. In both of these modifications, a reduced number of anatomical regions/blocks are assessed and still in a substantial number of cases, the inter-observer agreement differed significantly. Over 80% agreement in both typing and staging of αS pathology could be achieved when applying a new protocol, jointly designed by the BNE consortium. The BNE-protocol assessing αS-IR lesions in nine blocks offered advantages over the previous modified protocols because the agreement between the 22 observers was over 80% in most cases. Furthermore, in the BNE-protocol, the αS pathology is assessed as being present or absent and thus the quality of staining and the assessment of the severity of αS-IR pathology do not alter the inter-observer agreement, contrary to other assessment strategies. To reach these high agreement rates an entity of amygdala-predominant category was incorporated. In conclusion, here we report a protocol for assessing αS pathology that can achieve a high inter-observer agreement for both the assignment to brainstem, limbic, neocortical and amygdala-predominant categories of synucleinopathy and the Braak stages. © The Author(s) 2009.

β-Amyloid (Aβ) related pathology shows a range of lesions which differ both qualitatively and quantitatively. Pathologists, to date, mainly focused on the assessment of both of these aspects but attempts to correlate the findings with clinical phenotypes are not convincing. It has been recently proposed in the same way as 1 and α synuclein related lesions, also Aβ related pathology may follow a temporal evolution, i.e. distinct phases, characterized by a step-wise involvement of different brain-regions. Twenty-six independent observers reached an 81% absolute agreement while assessing the phase of Aβ, i.e. phase 1 = deposition of Aβ exclusively in neocortex, phase 2 = additionally in allocortex, phase 3 = additionally in diencephalon, phase 4 = additionally in brainstem, and phase 5 = additionally in cerebellum. These high agreement rates were reached when at least six brain regions were evaluated. Likewise, a high agreement (93%) was reached while assessing the absence/presence of cerebral amyloid angiopathy (CAA) and the type of CAA (74%) while examining the six brain regions. Of note, most of observers failed to detect capillary CAA when it was only mild and focal and thus instead of type 1, type 2 CAA was diagnosed. In conclusion, a reliable assessment of Aβ phase and presence/absence of CAA was achieved by a total of 26 observers who examined a standardized set of blocks taken from only six anatomical regions, applying commercially available reagents and by assessing them as instructed. Thus, one may consider rating of Aβ-phases as a diagnostic tool while analyzing subjects with suspected Alzheimer's disease (AD). Because most of these blocks are currently routinely sampled by the majority of laboratories, assessment of the Aβ phase in AD is feasible even in large scale retrospective studies. © Springer-Verlag 2009.

To determine the reliability of assessment of [alpha]-synuclein-immunoreactive ([alpha]S-IR) structures by neuropathologists, 28 evaluators from 17 centers of BrainNet Europe examined current methods and reproducibility of [alpha]S-IR evaluation using a tissue microarray (TMA) technique. Tissue microarray blocks were constructed of samples from the participating centers that contained [alpha]S-IR structures. Slides from these blocks were stained in each center and assessed for neuronal perikaryal inclusions, neurites, and glial cytoplasmic inclusions. The study was performed in 2 phases. First, the TMA slides were stained with the antibody of the center's choice. In this phase, 59% of the sections were of good or acceptable quality, and 4 of 9 antibodies used performed consistently. Differences in interpretation and categorization of [alpha]S-IR structures, however, led to differing results between the laboratories. Prior to the second phase, the neuropathologists participated in a training session on the evaluation of [alpha]S-IR structures. Based on the results of the first phase, selected antibodies using designated antigen retrieval methods were then applied to TMA slides in the second phase. When the designated methods of both staining and evaluation were applied, all 26 subsequently stained TMA sections evaluated were of good/acceptable quality, and a high level of concordance in the assessment of the presence or absence of specific [alpha]S-IR structures was achieved. A semiquantitative assessment of [alpha]S-IR neuronal perikaryal inclusions yielded agreements ranging from 49% to 82%, with best concordance in cortical core samples. These results suggest that rigorous methodology and dichotomized assessment (i.e. determining the presence or absence of [alpha]S-IR) should be applied, and that semiquantitative assessment can be recommended only for the cortical samples. Moreover, the study demonstrates that there are limitations in the scoring of [alpha]S-IR structures.

Amyloid-β-protein (A β) is generally assessed by neuropathologists in diagnostics. This BrainNet Europe (http://www.brainnet-europe.org/) (15 centres and 26 participants) study was carried out to investigate the reliability of such an assessment. In the first part of this trial, tissue microarray sections were stained with the antibody of each centre's choice. Reflecting the reality, seven antibodies and a plethora of pretreatment strategies were used. Ninety-two percent of the stainings were of good/acceptable quality and the estimation of presence of Aβaggregates yielded good results. However, a poor agreement was reached particularly regarding quantitative (density) and qualitative (diffuse/cored plaques) results. During a joint meeting, the clone 4G8 was determined to label best the fleecy/diffuse plaques, and thus, this clone and the formic acid pretreatment technique were selected for the second part of this study. Subsequently, all stained sections were of good/acceptable quality and again a high level of concordance of the dichotomized (presence/absence) assessment of plaques and CAA was achieved. However, even when only one antibody was used, the type of Aβ-aggregates (diffuse/cored), type of vessel and Vonsattel grade, were not reliably assigned. Furthermore, the quantification of lesions was far from reliable. In line with the first trial, the agreement while assessing density (some, moderate and many) was unimpressive. In conclusion, we can confirm the utility of immunohistochemical detection of Aβ-protein in diagnostics and research. It is noteworthy that to reach reproducible results a dichotomized assessment of Aβ-immunoreactivity rather than quantification and assignment of various types of lesions should be applied, particularly when comparing results obtained by different neuropathologists. © Springer-Verlag 2008.

Collections of human postmortem brains gathered in brain banks have underpinned many significant developments in the understanding of central nervous system (CNS) disorders and continue to support current research. Unfortunately, the worldwide decline in postmortem examinations has had an adverse effect on research tissue procurement, particularly from control cases (non-diseased brains). Recruitment to brain donor programmes partially addresses this problem and has been successful for dementing and neurodegenerative conditions. However, the collection of brains from control subjects, particularly from younger individuals, and from CNS disorders of sudden onset, remains a problem. Brain banks need to adopt additional strategies to circumvent such shortages. The establishment of brain bank networks allows data on, and access to, control cases and unusual CNS disorders to be shared, providing a larger resource for potential users. For the brain banks themselves, inclusion in a network fosters the sharing of protocols and development of best practice and quality control. One aspect of this collective experience concerns brain bank management, excellence in which is a prerequisite not only for gaining the trust of potential donors and of society in general, but also for ensuring equitable distribution to researchers of high quality tissue samples. This review addresses the legal, ethical and governance issues, tissue quality, and health and safety aspects of brain bank management and data management in a network, as well as the needs of users, brain bank staffing, donor programs, funding issues and public relations. Recent developments in research methodology present new opportunities for researchers who use brain tissue samples, but will require brain banks to adopt more complex protocols for tissue collection, preparation and storage, with inevitable cost implications for the future. © Springer-Verlag 2008.

It has been recognized that molecular classifications will form the basis for neuropathological diagnostic work in the future. Consequently, in order to reach a diagnosis of Alzheimer's disease (AD), the presence of hyperphosphorylated tau (HP-tau) and β-amyloid protein in brain tissue must be unequivocal. In addition, the stepwise progression of pathology needs to be assessed. This paper deals exclusively with the regional assessment of AD-related HP-tau pathology. The objective was to provide straightforward instructions to aid in the assessment of AD-related immunohistochemically (IHC) detected HP-tau pathology and to test the concordance of assessments made by 25 independent evaluators. The assessment of progression in 7-μm-thick sections was based on assessment of IHC labeled HP-tau immunoreactive neuropil threads (NTs). Our results indicate that good agreement can be reached when the lesions are substantial, i.e., the lesions have reached isocortical structures (stage V-VI absolute agreement 91%), whereas when only mild subtle lesions were present the agreement was poorer (I-II absolute agreement 50%). Thus, in a research setting when the extent of lesions is mild, it is strongly recommended that the assessment of lesions should be carried out by at least two independent observers. © 2008 The Authors.

To determine the reliability of assessment of a-synucleinimmunoreactive (aS-IR) structures by neuropathologists, 28 evaluators from 17 centers of BrainNet Europe examined current methods and reproducibility of aS-IR evaluation using a tissue microarray (TMA) technique. Tissue microarray blocks were constructed of samples from the participating centers that contained aS-IR structures. Slides from these blocks were stained in each center and assessed for neuronal perikaryal inclusions, neurites, and glial cytoplasmic inclusions. The study was performed in 2 phases. First, the TMA slides were stained with the antibody of the center's choice. In this phase, 59% of the sections were of good or acceptable quality, and 4 of 9 antibodies used performed consistently. Differences in interpretation and categorization of aS-IR structures, however, led to differing results between the laboratories. Prior to the second phase, the neuropathologists participated in a training session on the evaluation of aS-IR structures. Based on the results of the first phase, selected antibodies using designated antigen retrieval methods were then applied to TMA slides in the second phase. When the designated methods of both staining and evaluation were applied, all 26 subsequently stained TMA sections evaluated were of good/acceptable quality, and a high level of concordance in the assessment of the presence or absence of specific aS-IR structures was achieved. A semiquantitative assessment of aS-IR neuronal perikaryal inclusions yielded agreements ranging from 49% to 82%, with best concordance in cortical core samples. These results suggest that rigorous methodology and dichotomized assessment (i.e. determining the presence or absence of aS-IR) should be applied, and that semiquantitative assessment can be recommended only for the cortical samples. Moreover, the study demonstrates that there are limitations in the scoring of aS-IR structures. Copyright © 2008 by the American Association of Neuropathologists, Inc.

This interlaboratory study evaluated the reproducibility of the assessments of neuritic plaques and neurofibrillary tangles (NFTs)-the hallmark lesions of Alzheimer disease-and compared the staining between the BrainNet Europe centers. To reduce the topography-related inconsistencies in assessments, we used a 2-mm tissue microarray (TMA) technique. The TMA block included 42 core samples taken from 21 paraffin blocks. The assessments were done on Bielschowsky and Gallyas silver stains using an immunohistochemical (IHC) method with antibodies directed to beta-amyloid (IHC/Aβ) and hyperphosphorylated tau (IHC/HPtau). The staining quality and the assessments differed between the participants, being most diverse with Bielschowsky (good/acceptable stain in 53% of centers) followed by Gallyas (good/acceptable stain in 57%) and IHC/Aβ (good/acceptable stain in 71%). The most uniform staining quality and assessment was obtained with the IHC/HPtau method (good/acceptable stain in 94% of centers). The neuropathologic diagnostic protocol (Consortium to Establish a Registry for Alzheimer Disease, Braak and Braak, and the National Institute of Aging and Reagan [NIA-Reagan] Institute) that was used significantly influenced the agreement, being highest with NIA-Reagan (54%) recommendations. This agreement was improved by visualization of NFTs using the IHC/HPtau method. Therefore, the IHC/HPtau methodology to visualize NFTs and neuropil threads should be considered as a method of choice in a future diagnostic protocol for Alzheimer disease. Copyright © 2006 by the American Association of Neuropathologists, Inc.

Dementia, Alzheimer's disease (AD) being the most common cause of it, is a major and growing medical and social problem, particularly in the advanced age, with the highest rate in the population over 75 y. Recent sophisticated therapeutic measures require more sensitive diagnostic tests to recognize early stages of the disease. In this paper, the current neuronuclear imaging literature is reviewed with regard to early and differential diagnosis of dementia. Functional imaging with single photon emission computed tomography (SPECT) and positron emission tomography (PET) could provide the clinician with additional information complementary to morphological assessments, thus contributing to achieve a more adequate diagnosis, and also with information regarding prodromal stages of AD

This paper gives a brief description of the recently formalized International Mass Spectrometry Society (IMSS). It is presented here in order to increase awareness of the opportunities for collaboration in mass spectometry in an international context. It also describes the recent 15th International Mass Spectrometry Conference, held August/September 2000, in Barcelona. Each of the authors is associated with the IMSS. The 15th Conference, which covers all of mass spectrometry on a triennial basia, was chaired by Professor Emilio Gelpi of the Instituto de Investigaciones Biomedicas, Barcelona. The outgoing and founding President of the IMSS is Professor Graham Cooks, Purdue University, and the incoming President is Professor Nico Nibbering, University of Amsterdam. Similar material has been provided to the Editors of other journals that cover mass spectrometry. Copyright © 2001 John Wiley & Sons, Ltd.

Previous studies have demonstrated that intestinal preconditioning protects the organ from ischemia reperfusion damage. Xanthine oxidase mediating free radical generation contributes to the development of injury associated to ischemia reperfusion. Thus, any process able to modulate the oxygen free radical generation system could attenuate the injury. Also, it is known that nitric oxide is implicated in the preconditioning response. The aim of this work is to determine: (1) the effect of intestinal preconditioning on the xanthine oxidase system, (2) the relevance of this system in the development of injury, and (3) its relationship with nitric oxide. For this purpose, we have determined the activity of the xanthine dehydrogenase/xanthine oxidase system, the levels of its substrate (xanthine), and end-product (uric acid) and oxidant stress status in rat small intestine subjected to ischemic preconditioning. The effects of nitric oxide inhibition have also been evaluated. Results show that the percentage of xanthine dehydrogenase to xanthine oxidase conversion, xanthine, uric acid concentration, lipoperoxides, and reduced glutathione were significantly reduced in preconditioned rats irrespectively of nitric oxide inhibition. In summary, this work shows that oxidative stress in intestinal preconditioning is reduced as consequence of the diminished conversion of xanthine dehydrogenase to xanthine oxidase, and also as a consequence of the reduced availability of xanthine.

To validate the provisional findings of a number of smaller studies and explore additional determinants of characteristic diagnostic investigation results across the entire clinical spectrum of sporadic Creutzfeldt-Jakob disease (CJD), an international collaborative study was undertaken comprising 2451 pathologically confirmed (definite) patients. We assessed the influence of age at disease onset, illness duration, prion protein gene (PRNP) codon 129 polymorphism (either methionine or valine) and molecular sub-type on the diagnostic sensitivity of EEG, cerebral MRI and the CSF 14-3-3 immunoassay. For EEG and CSF 14-3-3 protein detection, we also assessed the influence of the time point in a patient's illness at which the investigation was performed on the likelihood of a typical or positive result. Analysis included a large subset of patients (n = 743) in whom molecular sub-typing had been performed using a combination of the PRNP codon 129 polymorphism and the form of protease resistant prion protein [type 1 or 2 according to Parchi et al. (Parchi P, Giese A, Capellari S, Brown P, Schulz-Schaeffer W, Windl O, Zerr I, Budka H, Kopp N, Piccardo P, Poser S, Rojiani A, Streichemberger N, Julien J, Vital C, Ghetti B, Gambetti P, Kretzschmar H. Classification of sporadic Creutzfeldt-Jakob disease based on molecular and phenotypic analysis of 300 subjects. Ann Neurol 1999; 46: 224-233.)] present in the brain. Findings for the whole group paralleled the subset with molecular sub-typing data available, showing that age at disease onset and disease duration were independent determinants of typical changes on EEG, while illness duration significantly influenced positive CSF 14-3-3 protein detection; changes on brain MRI were not influenced by either of these clinical parameters, but overall, imaging data were less complete and consequently conclusions are more tentative. In addition to age at disease onset and illness duration, molecular sub-type was re-affirmed as an important independent determinant of investigation results. In multivariate analyses that included molecular sub-type, time point of the investigation during a patient's illness was found not to influence the occurrence of a typical or positive EEG or CSF 14-3-3 protein result. A typical EEG was most often seen in MM1 patients and was significantly less likely in the MV1, MV2 and VV2 sub-types, whereas VV2 patients had an increased likelihood of a typical brain MRI. Overall, the CSF 14-3-3 immunoassay was the most frequently positive investigation (88.1%) but performed significantly less well in the very uncommon MV2 and MM2 sub-types. Our findings confirm a number of determinants of principal investigation results in sporadic CJD and underscore the importance of recognizing these pre-test limitations before accepting the diagnosis excluded or confirmed. Combinations of investigations offer the best chance of detection, especially for the less common molecular sub-types such as MV2 and MM2.

The implication of eicosanoid metabolism and its relationship with oxygen free radical production in the process of ischemia-reperfusion associated with rat pancreas transplantation has been explored in this study. For this purpose male Sprague-Dawley rats were classified as follows: group I, control animals not surgically manipulated; group II, pancreas transplantation, after 30 min preservation in UW solution; group III, pancreas transplantation after 12 h preservation under the same conditions; group IV, same as group III but with administration of SOD 5 min prior to organ revascularization. The results show post-transplantation increases in 6-keto-PGF1 alpha, TXB2, LTB4 and 12-HETE in pancreatic tissue independent of preservation time. The fact that SOD administration could reverse these increases even though an efficient xanthine oxidase irreversible inhibitor such as allopurinol was present in the preservation solution suggests that eicosanoid generation in the recipient rat would be mediated by an oxygen free radical dependent mechanism not exclusively dependent on endothelial xanthine oxidase activity.