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Background: Dementia with Lewy bodies (DLB) and Parkinson’s disease dementia (PDD) are differentiated by the time of onset of cognitive and motor symptoms (‘1-year rule’). We explored the neuropsychological continuum of DLB and PDD subjects with different timing of dementia onset. Objective: Our aim was to compare the neuropsychological profile of DLB and PDD patients with different timing of dementia onset. Methods: Neuropsychological findings at the diagnosis of dementia of 66 PDD and 42 DLB patients were retrospectively compared. Patients with PDD were divided into three tertile subgroups according to the time interval between the onset of parkinsonism and dementia (N = 24, 2–4 years; N = 17, 5–7 years; N = 25 ≥8 years, respectively). Results: DLB patients performed worse on the Stroop and semantic fluency tests than PDD, even in comparison to PD with early dementia onset. No significant differences among PDD subgroups were reported. Conclusion: Executive and semantic language tests could differentiate DLB and PD patients with earlier development of dementia relative to parkinsonism.

Background: It has been speculated that stains are neuroprotective and are associated with a reduced risk of Parkinson’s disease (PD), but only a few studies have investigated the influence of statins on the progression of PD. Objective: To evaluate whether long-term statin use may affect motor progression in a large cohort of de novo patients with PD. Methods: We conducted a 4-year retrospective observational cohort study to assess patients with PD. The patients were consecutively recruited from a single tertiary center between January 2015 and January 2017. Information on motor function was obtained using the MDS-Unified Parkinson Disease Rating Scale (UPDRS)-III and all subjects were extensively characterized, including information about lifestyle habits, cardiovascular risk factors and cholesterol blood levels. Results: Of the 181 participants included in the study, 104 patients were evaluated for eligibility (42 patients were exposed to statin therapies and 62 were not treated with statins). They presented similar scores in UPDRS III at baseline but the statin users had a lower motor impairment at 4 years compared to non-user PD patients. Additionally, statin treatment resulted in slower progression of the rigidity score of UPDRS over 4 years. No other significant differences were observed between PD patients with and without statins. Conclusion: Early PD patients with long-term statin usage showed lower motor deterioration after 4 years of disease duration compared with patients not taking statins at diagnosis, suggesting a possible influence of statins on disease progression in PD. Further investigation is warranted to understand the potential beneficial effects of statin treatment on clinical symptoms in PD.

α-syn aggregates represent the pathological hallmark of synucleinopathies as well as a frequent copathology (almost 1/3 of cases) in AD. Recent research indicates a potential role of α-syn species, measured in CSF with conventional analytical techniques, in the differential diagnosis between AD and synucleinopathies (such as DLB). Pioneering studies report the detection of α-syn in blood, however, conclusive investigations are controversial. Ultrasensitive seed amplification techniques, enabling the selective quantification of α-syn seeds, may represent an effective solution to identify the α-syn component in AD and facilitate a biomarker-guided stratification. We performed a PubMed-based review of the latest findings on α-syn-related biomarkers for AD, focusing on bodily fluids. A dissertation on the role of ultrasensitive seed amplification assays, detecting α-syn seeds from different biological samples, was conducted. α-syn may contribute to progressive AD neurodegeneration through cross-seeding especially with tau protein. Ultrasensitive seed amplification techniques may support a biomarker-drug co-development pathway and may be a pathophysiological candidate biomarker for the evolving ATX(N) system to classify AD and the spectrum of primary NDDs. This would contribute to a precise approach to AD, aimed at implementing disease-modifying treatments.

Introduction The clinical validation and qualification of biomarkers reflecting the complex pathophysiology of neurodegenerative diseases (NDDs) is a fundamental challenge for current drug discovery and development and next-generation clinical practice. Novel ultrasensitive detection techniques and protein misfolding amplification assays hold the potential to optimize and accelerate this process. Areas covered Here we perform a PubMed-based state of the art review and perspective report on blood-based ultrasensitive detection techniques and protein misfolding amplification assays for biomarkers discovery and development in NDDs. Expert opinion Ultrasensitive assays represent innovative solutions for blood-based assessments during the entire Alzheimer's disease (AD) biological and clinical continuum, for contexts of use (COU) such as prediction, detection, early diagnosis, and prognosis of AD. Moreover, cerebrospinal fluid (CSF)-based misfolding amplification assays show encouraging performance in detecting α-synucleinopathies in prodromal or at-high-risk individuals and may serve as tools for patients' stratification by the presence of α-synuclein pathology. Further clinical research will help overcome current methodological limitations, also through exploring multiple accessible bodily matrices. Eventually, integrative longitudinal studies will support precise definitions for appropriate COU across NDDs.

International audience; Introduction: Tau protein misfolding and accumulation in toxic species is a critical pathophysiological process of Alzheimer's Disease (AD) and other neurodegenerative disorders (NDDs). Tau biomarkers, namely cerebrospinal fluid (CSF) total-tau (t-tau), 181-phosphorylated tau (p-tau) and tau-PET tracers, have been recently embedded in the diagnostic criteria for AD. Nevertheless, the role of tau as a diagnostic and prognostic biomarker for other NDDs remains controversial.Areas covered: We performed a systematical PubMed-based review of the most recent advances in tau-related biomarkers for NDDs. We focused on papers published from 2015 to 2020 assessing the diagnostic or prognostic value of each biomarker.Expert opinion: The assessment of tau biomarkers in alternative easily accessible matrices, through the development of ultrasensitive techniques, represents the most significant perspective for AD-biomarker research. In NDDs, novel tau isoforms (e.g., p-tau217) or proteolytic fragments (e.g., N-terminal fragments) may represent candidate diagnostic and prognostic biomarkers and may help monitoring disease progression. Protein misfolding amplification assays, allowing the identification of different tau strains (e.g. 3R- vs. 4R-tau) in CSF, may constitute a breakthrough for the in vivo stratification of NDDs. Tau-PET may help tracking the spatial-temporal evolution of tau pathophysiology in AD but its application outside the AD-spectrum deserves further studies.

Intravascular large B-cell lymphoma (IVLBCL) is a very rare form of extranodal lymphoma, characterized by the proliferation of neoplastic B cells within the lumen of small vessels. Due to its high aggressivity, for years the prognosis had been really poor with only anectodical cases of remission after traditional chemotherapy. More recently, new therapeutic protocols allowed a significant increase in overall survival. It can virtually involve every organ, being skin and central nervous system the most affected. The clinical presentation is often unspecific and insidious; therefore, diagnosis can be challenging. Tissue biopsy, in particular random deep skin biopsy, is the gold standard for definitive diagnosis. We describe the case of a 58-year-old woman with a previous diagnosis of myelofibrosis, who presented with a rapidly progressive neurological deterioration and a brain MRI suggestive of Progressive Multifocal Leukoencephalopathy. Due to the absence of BK and JC viruses in cerebrospinal fluid and the presence of severe myalgias and subcutaneous nodules, a skin and muscle biopsy was performed, allowing diagnosis of IVLBCL. We describe the diagnostic pitfalls of this case, briefly reviewing existing literature about IVLBCL.

The equilibria between Mn3+ and phosphate ions have been studied, at 25°C in 3M(Li+, H+)ClO4− media, by measuring the potential of the Mn3+Mn2+ half-cell at a series of [H+] as a function of the [H3PO4] and of the [Mn(III)]. The [H+] values ranged from 0.5 to 3M, while [Mn(III)] was varied between 5 × 10−5 and 10−3M. At each [H+] level the [H3PO4] was increased up to 0.1M. The data log [ Mn 3+ ] = ƒ([ H + ], [ H 3 PO r ]) , which indicate that only a small proportion of the reagents can be transformed into reaction products without the formation of a precipitate, may be explained with the existence of MnH2PO42+, Mn(H2PO4)2+ and of MNHPO4+, which most probably is a hydrolytic species: Mn(OH)H2PO4+. The equilibrium constants for the formation of these complexes are given.