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Neuropathologically, Parkinson's disease (PD) and dementia with Lewy bodies (DLB) are characterized by the accumulation of insoluble aggregates of α-synuclein (α-syn) in the Lewy bodies (LBs). In addition to full-length α-syn fibrils, C-terminally truncated α-syn is also abundant in the LBs that acts as seeds and facilitates the aggregation of the full-length α-syn

A seconda di come definiamo la diplomazia pubblica (PD), le sue radici possono essere fatte risalire al periodo tra le due guerre, agli anni '40, o più recentemente, agli anni '60 e all'era post guerra fredda. Attualmente, politici, diplomatici e studiosi sono sempre più attratti, interessati e coinvolti nella pratica e nella teoria di questo campo impegnativo e in rapidissimo sviluppo. L'accademia, così come il mondo della politica e della diplomazia, si stanno sforzando di capire da un lato, modellare e influenzare dall'altro, il flusso di impegno diplomatico pubblico che può lanciare e sostenere molteplici dialoghi con i pubblici stranieri in una strada a doppio senso senza precedenti, ma anche, inevitabilmente, permette al lato oscuro della disinformazione e della propaganda di trarre vantaggio da un ambiente diplomatico sempre più digitalizzato.

Objective:Neuronal loss in the substantia nigra pars compacta (SNpc) in Parkinson's disease (PD) is not uniform as dopamine neurons from the ventral tier are lost more rapidly than those of the dorsal tier. Identifying the intrinsic differences that account for this differential vulnerability may provide a key for developing new treatments for PD. Method:Here we compared the RNA‐sequenced transcriptomes of ~100 laser captured micro‐dissected SNpc neurons from each tier from seven healthy controls. Results:Expression levels of dopaminergic markers were similar across the tiers while markers specific to the neighbouring ventral tegmental area were virtually undetected. After accounting for unwanted sources of variation, we identified one hundred and six differentially expressed genes (DEGs) between the SNpc tiers. The genes higher in the dorsal/resistant SNpc tier neurons displayed coordinated patterns of expression across the human brain, their protein products had more interactions than expected by chance and they demonstrated evidence of functional convergence. No significant shared functionality was found for genes higher in the ventral/vulnerable SNpc tier. Surprisingly but importantly, none of the identified DEGs were among the familial PD genes or genome‐wide associated loci. Finally, we found some DEGs in opposite tier orientation between human and analogous mouse populations. Interpretation:Our results highlight functional enrichments of vesicular trafficking, ion transport/homeostasis and oxidative stress genes showing higher expression in the resistant neurons of the SNpc dorsal tier. Furthermore, the comparison of gene expression variation in human and mouse SNpc populations strongly argues for the need of human‐focused Omics studies.

α-Synuclein (α-syn) phosphorylation at serine 129 (pS129–α-syn) is substantially increased in Lewy body disease, such as Parkinson’s disease (PD) and dementia with Lewy bodies (DLB). However, the pathogenic relevance of pS129–α-syn remains controversial, so we sought to identify when pS129 modification occurs during α-syn aggregation and its role in initiation, progression and cellular toxicity of disease. Using diverse aggregation assays, including real-time quaking-induced conversion (RT-QuIC) on brain homogenates from PD and DLB cases, we demonstrated that pS129–α-syn inhibits α-syn fibril formation and seeded aggregation. We also identified lower seeding propensity of pS129–α-syn in cultured cells and correspondingly attenuated cellular toxicity. To build upon these findings, we developed a monoclonal antibody (4B1) specifically recognizing nonphosphorylated S129–α-syn (WT–α-syn) and noted that S129 residue is more efficiently phosphorylated when the protein is aggregated. Using this antibody, we characterized the time-course of α-syn phosphorylation in organotypic mouse hippocampal cultures and mice injected with α-syn preformed fibrils, and we observed aggregation of nonphosphorylated α-syn followed by later pS129–α-syn. Furthermore, in postmortem brain tissue from PD and DLB patients, we observed an inverse relationship between relative abundance of nonphosphorylated α-syn and disease duration. These findings suggest that pS129–α-syn occurs subsequent to initial protein aggregation and apparently inhibits further aggregation. This could possibly imply a potential protective role for pS129–α-syn, which has major implications for understanding the pathobiology of Lewy body disease and the continued use of reduced pS129–α-syn as a measure of efficacy in clinical trials.

Several studies have confirmed the α-synuclein real-time quaking-induced conversion (RT-QuIC) assay to have high sensitivity and specificity for Parkinson’s disease. However, whether the assay can be used as a robust, quantitative measure to monitor disease progression, stratify different synucleinopathies and predict disease conversion in patients with idiopathic REM sleep behaviour disorder remains undetermined. The aim of this study was to assess the diagnostic value of CSF α-synuclein RT-QuIC quantitative parameters in regard to disease progression, stratification and conversion in synucleinopathies.We performed α-synuclein RT-QuIC in the CSF samples from 74 Parkinson’s disease, 24 multiple system atrophy and 45 idiopathic REM sleep behaviour disorder patients alongside 55 healthy controls, analysing quantitative assay parameters in relation to clinical data.α-Synuclein RT-QuIC showed 89% sensitivity and 96% specificity for Parkinson’s disease. There was no correlation between RT-QuIC quantitative parameters and Parkinson’s disease clinical scores (e.g. Unified Parkinson’s Disease Rating Scale motor), but RT-QuIC positivity and some quantitative parameters (e.g. Vmax) differed across the different phenotype clusters. RT-QuIC parameters also added value alongside standard clinical data in diagnosing Parkinson’s disease. The sensitivity in multiple system atrophy was 75%, and CSF samples showed longer T50 and lower Vmax compared to Parkinson’s disease. All RT-QuIC parameters correlated with worse clinical progression of multiple system atrophy (e.g. change in Unified Multiple System Atrophy Rating Scale). The overall sensitivity in idiopathic REM sleep behaviour disorder was 64%. In three of the four longitudinally followed idiopathic REM sleep behaviour disorder cohorts, we found around 90% sensitivity, but in one sample (DeNoPa) diagnosing idiopathic REM sleep behaviour disorder earlier from the community cases, this was much lower at 39%. During follow-up, 14 of 45 (31%) idiopathic REM sleep behaviour disorder patients converted to synucleinopathy with 9/14 (64%) of convertors showing baseline RT-QuIC positivity.In summary, our results showed that α-synuclein RT-QuIC adds value in diagnosing Parkinson’s disease and may provide a way to distinguish variations within Parkinson’s disease phenotype. However, the quantitative parameters did not correlate with disease severity in Parkinson’s disease. The assay distinguished multiple system atrophy patients from Parkinson’s disease patients and in contrast to Parkinson’s disease, the quantitative parameters correlated with disease progression of multiple system atrophy. Our results also provided further evidence for α-synuclein RT-QuIC having potential as an early biomarker detecting synucleinopathy in idiopathic REM sleep behaviour disorder patients prior to conversion. Further analysis of longitudinally followed idiopathic REM sleep behaviour disorder patients is needed to better understand the relationship between α-synuclein RT-QuIC signature and the progression from prodromal to different synucleinopathies.

Rare deletions and duplications on the long arm of Chromosome 21 have previously been reported in many patients with craniofacial and developmental phenotypes. However, this Down Syndrome Critical Region (DSCR) contains multiple genes, making identifying a single causative gene difficult. Here, we report a case of a boy with bicoronal craniosynostosis, facial dysmorphism, developmental delay, and intellectual impairment who was found by whole genome sequencing to have a homozygous missense mutation in the Single-Minded Homolog 2 (SIM2) gene (c.461 AG, p.Tyr154Cys) within the DSCR. SIM2 encodes an essential bHLH and PAS domain transcription factor expressed during fetal brain development and acts as a master regulator of neurogenesis. This variant is globally very rare, segregates in the family, and is predicted to be highly deleterious by in silico analysis, 3D molecular modeling of protein structure, and functional analysis of zebrafish models. Zebrafish expressing the human SIM2

Aggregated α-synuclein (αSyn) protein is a core pathological feature of Parkinson’s disease (PD) and dementia with Lewy bodies (DLB). Both PD and DLB demonstrate the presence of diverse intracellular α-synuclein (αSyn) species, including C-terminally truncated αSyn (C-αSyn), although it is unknown how C-αSyn species contribute to disease progression. Using recombinant C-αSyn and PD and DLB brain lysates as seeds in the real-time quaking-induced conversion (RT-QuIC) assay, we explored how C-αSyn may be involved in disease stratification. Comparing the seeding activity of aqueous-soluble fractions to detergent-soluble fractions, and using αSyn 1-130 as substrate for the RT-QuIC assay, the temporal cortex seeds differentiated PD and DLB from healthy controls. In contrast to the temporal cortex, where PD and DLB could not be distinguished, αSyn 1-130 seeded by the detergent-soluble fractions from the PD frontal cortex demonstrated greater seeding efficiency compared to the DLB frontal cortex. Moreover, proteinase K-resistant (PKres) fragments from the RT-QuIC end products using C-αSyn 1-130 or C-αSyn 1-115 were more obvious in the frontal cortex compared to the temporal cortex. Morphological examinations of RT-QuIC end products showed differences in the size of the fibrils between C-αSyn 1-130 and C-αSyn 1-115, in agreement with the RT-QuIC results. These data show that C-αSyn species can distinguish PD from DLB and suggest diversity in αSyn species across these synucleinopathies, which could play a role in disease progression.

Gastrointestinal (GI) alpha-synuclein (ASN) detection may represent a clinically useful biomarker of Parkinson’s disease (PD), but this has been challenged by conflicting results of recent studies employing different immunohistochemical (IHC) methods and reporting diverse morphological patterns with variable biological interpretation. To increase sensitivity and specificity, we applied three different techniques to detect different possible conformations of ASN in GI tissue derived from biopsies of the GI tract, which were obtained from a longitudinally followed, clinically well-characterized cohort of PD subjects and healthy controls (HC) (Oxford Discovery study). With IHC, we used antibodies reactive for total (T-ASN-Abs), phosphorylated (P-ASN-Abs) and oligomeric (O-ASN-Abs) ASN; with the ASN Proximity Ligation Assay (AS-PLA), we targeted oligomeric ASN species specifically; finally, with the Paraffin-Embedded Tissue Blot (PET-Blot) we aimed to detect fibrillary conformations of ASN specifically. Optimisation and validation of the PET-Blot and PLA techniques was carried out with studies on brain tissue from subjects with ASN pathology, and these experiments were used to gain insight into morphology and distribution of different conformational variants of ASN in the brain of subjects with Lewy pathology. We specified all the detected morphological staining patterns with each technique interpreting them as pathologic or non-specific. Correlation to clinical symptoms was assessed to investigate the potential predictive or diagnostic value of specific staining patterns as biomarkers. A total of 163 GI tissue blocks were collected from 51 PD patients (113 blocks) and 21 healthy controls (50 blocks). In 31 PD patients, GI biopsies had been taken before PD diagnosis (Prodromal PD group); while in 20 PD patients biopsies were obtained after PD diagnosis (Manifest PD group). The majority of these tissues blocks were from large intestine (62%), followed by small intestine (21%), stomach (10%) and oesophagus (7%). With IHC, four ASN staining patterns were detected in GI tissue (Neuritic, Ganglionic, Epithelial, and Cellular), while two distinct staining patterns were detected with AS-PLA (cellular and diffuse signal) and with AS-PET-Blot (ASN-localised and peri-crypt signal). The level of agreement between different techniques was generally low, and no single technique or staining pattern was able to reliably distinguish PD patients (Prodromal or Manifest) from HC. Overall, our study suggests that even specific detection of ASN conformational variants currently considered pathologic was not adequate for the prediction of PD. Future studies with these or other novel techniques focusing on the upper part of the GI tract could overcome current limitations in sensitivity and specificity.

The differential diagnosis of Creutzfeldt-Jakob disease (CJD) from other, sometimes treatable, neurological disorders is challenging, owing to the wide phenotypic heterogeneity of the disease. Real-time quaking-induced prion conversion (RT-QuIC) is a novel ultrasensitive in vitro assay, which, at variance with surrogate neurodegenerative biomarker assays, specifically targets the pathological prion protein (PrPSc). In the studies conducted to date in CJD, cerebrospinal fluid (CSF) RT-QuIC showed good diagnostic sensitivity (82–96%) and virtually full specificity. In the present study, we investigated the diagnostic value of both prion RT-QuIC and surrogate protein markers in a large patient population with suspected CJD and then evaluated the influence on CSF findings of the CJD type, and the associated amyloid-β (Aβ) and tau neuropathology. RT-QuIC showed an overall diagnostic sensitivity of 82.1% and a specificity of 99.4%. However, sensitivity was lower in CJD types linked to abnormal prion protein (PrPSc) type 2 (VV2, MV2K and MM2C) than in typical CJD (MM1). Among surrogate proteins markers (14-3-3, total (t)-tau, and t-tau/phosphorylated (p)-tau ratio) t-tau performed best in terms of both specificity and sensitivity for all sCJD types. Sporadic CJD VV2 and MV2K types demonstrated higher CSF levels of p-tau when compared to other sCJD types and this positively correlated with the amount of tiny tau deposits in brain areas showing spongiform change. CJD patients showed moderately reduced median Aβ42 CSF levels, with 38% of cases having significantly decreased protein levels in the absence of Aβ brain deposits. Our results: (1) support the use of both RT-QuIC and t-tau assays as first line laboratory investigations for the clinical diagnosis of CJD; (2) demonstrate a secondary tauopathy in CJD subtypes VV2 and MV2K, correlating with increased p-tau levels in the CSF and (3) provide novel insight into the issue of the accuracy of CSF p-tau and Aβ42 as markers of brain tauopathy and β-amyloidosis. Electronic supplementary material The online version of this article (doi:10.1007/s00401-017-1683-0) contains supplementary material, which is available to authorized users.

This is a comparative effort to discuss the impact of defeat and surrender on Japanese and Italian international status and relations after WWII. I will start from two main points: (1) in discussing both countries the price of defeat is central in understanding political self-perceptions and external relations from the early post-war period to the Cold War era; (2) a comparative analysis of Italy and Japan based on themes such as memories of the war, post war regional grouping, economic recovery and growth as well as national paths throughout the Cold War era, calls attention to the similarity of their starting point as defeated nations. The main argument is that the implications of defeat and post WWII peace-making in Italy and Japan were significant and long lasting. This chapter will substantiate this argument by reflecting on the meanings of defeat and identifying a set of comparable moments in post war Italian and Japanese self-perception and international relations.

Prion diseases are characterized by tissue accumulation of a misfolded, β-sheet-enriched isoform (scrapie prion protein (PrPSc)) of the cellular prion protein (PrPC). At variance with PrPC, PrPSc shows a partial resistance to protease digestion and forms highly aggregated and detergent-insoluble polymers, two properties that have been consistently used to distinguish the two proteins. In recent years, however, the idea that PrPSc itself comprises heterogeneous species has grown. Most importantly, a putative proteinase K (PK)-sensitive form of PrPSc (sPrPSc) is being increasingly investigated for its possible role in prion infectivity, neurotoxicity, and strain variability. The study of sPrPSc, however, remains technically challenging because of the need of separating it from PrPC without using proteases. In this study, we have systematically analyzed both PK resistance and the aggregation state of purified PrPSc across the whole spectrum of the currently characterized human prion strains. The results show that PrPSc isolates manifest significant strain-specific differences in their PK digestion profile that are only partially explained by differences in the size of aggregates, suggesting that other factors, likely acting on PrPSc aggregate stability, determine its resistance to proteolysis. Fully protease-sensitive low molecular weight aggregates were detected in all isolates but in a limited proportion of the overall PrPSc (i.e. Background: Protease resistance and aggregation state, two fundamental properties of abnormal prion protein (PrPSc), remain significantly unexplored. Results: Prion isolates show differences in PrPSc PK digestion profile that are only partially explained by differences in aggregate size. Conclusion: Molecular factors, likely acting on aggregate stability, significantly influence PrPSc PK sensitivity. Significance: The study provides insight into prion strain variability with respect to PrPSc PK sensitivity and aggregation state.

Prion diseases, also known as transmissible spongiform encephalopathies (TSEs), are a group of fatal neurodegenerative disorders affecting humans and other mammalian species. The central event in TSE pathogenesis is the conformational conversion of the cellular prion protein,PrPC, into the aggregate,β-sheet rich, amyloidogenic form,PrPSc. Increasing evidence indicates that distinctPrPScconformers, forming distinct ordered aggregates, can encipher the phenotypic TSE variants related to prion strains. Prion strains are TSE isolates that, after inoculation into syngenic hosts, cause disease with distinct characteristics, such as incubation period, pattern ofPrPScdistribution, and regional severity of histopathological changes in the brain. In analogy with other amyloid forming proteins,PrPSctoxicity is thought to derive from the existence of various intermediate structures prior to the amyloid fiber formation and/or their specific interaction with membranes. The latter appears particularly relevant for the pathogenesis of TSEs associated with GPI-anchoredPrPSc, which involves major cellular membrane distortions in neurons. In this review, we update the current knowledge on the molecular mechanisms underlying three fundamental aspects of the basic biology of prions such as the putative mechanism of prion protein conversion to the pathogenic formPrPScand its propagation, the molecular basis of prion strains, and the mechanism of induced neurotoxicity byPrPScaggregates.

Transmissible spongiform encephalopathies (TSEs) are neurodegenerative disorders caused by PrP(Sc), or prion, an abnormally folded form of the cellular prion protein (PrP(C)). The abundant expression of PrP(C) in the central nervous system (CNS) is a requirement for prion replication, yet despite years of intensive research the physiological function of PrP(C) still remains unclear. Several routes of investigation point out a potential role for PrP(C) in axon growth and neuronal development. Thus, we undertook a detailed analysis of the spatial and temporal expression of PrP(C) during mouse CNS development. Our findings show regional differences of the expression of PrP, with some specific white matter structures showing the earliest and highest expression of PrP(C). Indeed, all these regions are part of the thalamolimbic neurocircuitry, suggesting a potential role of PrP(C) in the development and functioning of this specific brain system.

I should like to begin by making it clear that the aim of this chapter is basically to elaborate the idea of ‘agreement on disagreement’. I readily admit, right at the start, that this is quite a paradoxical definition which does, however, help us significantly in understanding the rules of peace diplomacy in the years 1945–7. Secondly, my aim is not to provide a detailed reconstruction of day-to-day diplomacy at the CFM, but rather to isolate those issues which contributed to force the negotiators to make their positions clear — even at the cost of a breakdown in negotiations — and those compromise solutions which were elaborated in order to reduce the danger of such a disappointing conclusion of the CFM’s meetings. I shall also hint at the historiographical debate on the origins of the Cold War from the point of view of my specific interest in post-World War II peace-making. Indeed, the crucial passage from wartime peace thinking to post-war practices of pacification has not been fully explored by diplomatic historians. The reason for this is, of course, apparent: the Cold War cast a dark shadow on post-war Allied peacemaking strategies as a whole. However, the failure of the former wartime Allies to elaborate an overall settlement after World War II should not lead us to conclude that the study of peace diplomacy in itself is irrelevant. As I shall demonstrate, the importance of the issue can be seen in a different perspective today, because the need to cast light on the phase of transition from wartime to post-war international relations is much clearer in the present unstable scenario.

The basic aim of this chapter is to put into focus the question of the theory and practice of peace-making in the post-World War II period. In my previous work on the Italian peace settlement I noted that peace diplomacy following the end of World War II has been little studied.’ It seemed to me as if the cold war had cast a dark shadow on post-war Allied peacemaking strategies as a whole. As a result one could definitely see that a major change in the art of making peace had come about after 1945, but there was very little in the historiography to suggest why, how and when this change took place. In particular the crucial passage from war-time peace thinking to post-war practice of pacification had not been fully explored by diplomatic historians.