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Alzheimer’s Disease (AD) is the most common form of dementia. Regarding physiopathology, the key event is currently considered the aggregation and deposition of the beta-amyloid peptide (Aβ). However, neuroinflammation is postulated to play an essential role. Besides altered cognition, one of the main causes of distress in caregivers of AD patients is represented by Behavioural and Psychological Symptoms of Dementia (BPSD). Among them, aggression and agitation (A/A) represent a serious clinical problem, requiring qualified people and specialized structures. BPSD biological bases are still unknown and no definitive pharmacological treatments are available. Translocator protein 18-kDa (TSPO-18) is a receptor located on the outer mitochondrial membrane, formerly known as the Peripheral Benzodiazepine Receptor due to its pharmacological properties. TSPO is up-regulated in microglia in AD and is considered a biomarker of neuroinflammation, employed as a target for PET tracers (e.g., PK11195). The endogenous ligand is DBI (Diazepam Binding Inhibitor) that acts as an inverse agonist on GABAA receptors as well (i.e., as an anxiogenic peptide). TSPO transports cholesterol from cytoplasm to mitochondria in order to start the biosynthesis of neurosteroids. A reduction in TSPO expression in PBMCs and changes in serum neurosteroids levels have been shown in patients with anxiety disorder. Moreover, exon 4 of the TSPO gene contains a SNP called rs6971 (Ala147Thr substitution) that has been associated to separation anxiety. Finally, TSPO is also expressed on the plasma membrane of peripheral blood monocytes, where regulates chemotaxis and the passage through the blood-brain barrier (BBB) for contributing to the inflammatory milieu. Given TSPO involvement in neuroinflammation, steroids’ biosynthesis and anxiety genesis, this receptor seems an interesting target of study for understanding BPSD. At the moment, we genotyped 40 AD patients for rs6971 and we measured TSPO mRNA levels in their PBMC. Moreover, we assessed neurotrophins and DBI serum concentrations in the same patients. All the patients were screened for BPSD with the NPI and disease severity was evaluated by the MMSE. Moreover, we performed chemotaxis assays using THP-1 cells (acute myeloid leukaemia cell line) and MCP-1/Aβ peptide as chemoattractants, in order to get preliminary results about cellular migration in the presence of Aβ. We plan to run the same experiments on monocytes obtained from our patients. Further step will be including a model of BBB (transmigration assay). Our final goal is to find out whether these biological aspects could be linked to the presence of more or less severe BPSD, in order to cast light on the real determinants of these serious dementia-associated symptoms

Combined approaches have become a successful technique for CQ answering over ontologies. Existing algorithms, however, are restricted to the logics underpinning the OWL 2 profiles. Our goal is to make combined approaches applicable to a wider range of ontologies. We focus on RSA: a class of Horn ontologies that extends the profiles while ensuring tractability of standard reasoning. We show that CQ answering over RSA ontologies without role composition is feasible in NP. Our reasoning procedure generalises the combined approach for ELHO and DL-LiteR using an encoding of CQ answering into fact entailment w.r.t. a logic program with function symbols and stratified negation. Our results have significant practical implications since many out-of-profile Horn ontologies are RSA.

OWL 2 EL is a popular ontology language that is based on the EL family of description logics and supports regular role inclusions,axioms that can capture compositional properties of roles such as role transitivity and reflexivity. In this thesis, we present several novel complexity results and algorithms for answering expressive queries over OWL 2 EL knowledge bases (KBs) with regular role inclusions. We first focus on the complexity of conjunctive query (CQ) answering in OWL 2 EL and show that the problem is PSpace-complete in combined complexity, the complexity measured in the total size of the input. All the previously known approaches encode the regular role inclusions using finite automata that can be worst-case exponential in size, and thus are not optimal. In our PSpace procedure, we address this problem by using a novel, succinct encoding of regular role inclusions based on pushdown automata with a bounded stack. Moreover, we strengthen the known PSpace lower complexity bound and show that the problem is PSpace-hard even if we consider only the regular role inclusions as part of the input and the query is acyclic; thus, our algorithm is optimal in knowledge base complexity, the complexity measured in the size of the KB, as well as for acyclic queries. We then study graph queries for OWL 2 EL and show that answering positive, converse- free conjunctive graph queries is PSpace-complete. Thus, from a theoretical perspective, we can add navigational features to CQs over OWL 2 EL without an increase in complexity. Finally, we present a practicable algorithm for answering CQs over OWL 2 EL KBs with only transitive and reflexive composite roles. None of the previously known approaches target transitive and reflexive roles specifically, and so they all run in PSpace and do not provide a tight upper complexity bound. In contrast, our algorithm is optimal: it runs in NP in combined complexity and in PTime in KB complexity. We also show that answering CQs is NP-hard in combined complexity if the query is acyclic and the KB contains one transitive role, one reflexive role, or nominals—concepts containing precisely one individual.

Combined approaches have become a successful technique for CQ answering over ontologies. Existing algorithms, however, are restricted to the logics underpinning the OWL 2 profiles. Our goal is to make combined approaches applicable to a wider range of ontologies. We focus on RSA: a class of Horn ontologies that extends the profiles while ensuring tractability of standard reasoning. We show that CQ answering over RSA ontologies without role composition is feasible in NP. Our reasoning procedure generalises the combined approach for ELHO and DL-LiteR using an encoding of CQ answering into fact entailment w.r.t. a logic program with function symbols and stratified negation. Our results have significant practical implications since many out-of-profile Horn ontologies are RSA.

Introduction The surgical goal in glioblastoma treatment is the maximal safe resection of the tumor. Currently the lack of consensus on surgical technique opens different approaches. This study describes the “perilesional technique” and its outcomes in terms of the extent of resection, progression free survival and overall survival. Methods Patients included (n = 40) received a diagnosis of glioblastoma and underwent surgery using the perilesional dissection technique at “San Gerardo Hospital”between 2018 and 2021. The tumor core was progressively isolated using a circumferential movement, healthy brain margins were protected with Cottonoid patties in a “shingles on the roof” fashion, then the tumorwas removed en bloc. Intraoperative ultrasound (iOUS) was used and at least 1 bioptic sample of “healthy” margin of the resection was collected and analyzed. The extent of resection was quantified. Extent of surgical resection (EOR) and progression free survival (PFS)were safety endpoints of the procedure. Results Thirty-four patients (85%) received a gross total resection(GTR) while 3 (7.5%) patients received a sub-total resection (STR), and 3 (7.5%) a partial resection (PR). The mean post-operative residual volume was 1.44 cm3 (range 0–15.9 cm3).During surgery, a total of 76 margins were collected: 51 (67.1%) were tumor free, 25 (32.9%) were infiltrated. The median PFS was 13.4 months, 15.3 in the GTR group and 9.6 months in the STR-PR group. Conclusions Perilesional resection is an efficient technique which aims to bring the surgeon to a safe environment, carefully reaching the “healthy” brain before removing the tumoren bloc. This technique can achieve excellent tumor margins, extent of resection, and preservation of apatient’s functions.

Background Immunological causes of parkinsonism are very rare and usually characterized by early presentation, poor response to levodopa, and additional clinical features. Case presentation We describe a 58-year-old white man who presented with a 1-year history of gait disturbance with disequilibrium leading to falls. We report an association between parkinsonism and presence of anti-glutamic acid decarboxylase antibodies in his cerebrospinal fluid, discussing clinical presentation and follow-up. Conclusions Besides the possibility of a casual association, this case allows us to hypothesize an alternative pathophysiological mechanism of parkinsonism implying interference with glutamic acid decarboxylase and gamma-aminobutyric acid functions, eventually resulting in basal ganglia circuit dysregulation.

Behavioral dysfunctions (BPSD) represent the most important problem in Alzheimer's dementia (AD) management. We assessed the serum levels of two myokines in AD patients, preliminary investigating, as secondary aim, their role as potential biomarkers for agitation/aggression (AA) and aberrant motor behavior (AMB): irisin, since it is able to modify the motor pattern, and BDNF, since it was transcribed following irisin stimulation. Forty AD patients were recruited and characterized according to the expressed neuropsychiatric syndrome. Myokines were measured by ELISA. Irisin serum levels were slightly elevated in AA+ patients (+ 10.0%; p

HSPA8/hsc70 (70-kDa heat shock cognate) chaperone protein exerts multiple protective roles. Beside its ability to confer to the cells a generic resistance against several metabolic stresses, it is also involved in at least two critical processes whose activity is essential in preventing Parkinson's disease (PD) pathology. Actually, hsc70 protein acts as the main carrier of chaperone-mediated autophagy (CMA), a selective catabolic pathway for alpha-synuclein, the main pathogenic protein that accumulates in degenerating dopaminergic neurons in PD. Furthermore, hsc70 efficiently fragments alpha-synuclein fibrils in vitro and promotes depolymerization into non-toxic alpha-synuclein monomers. Considering that the mitochondrial complex I inhibitor rotenone, used to generate PD animal models, induces alpha-synuclein aggregation, this study was designed in order to verify whether rotenone exposure leads to hsc70 alteration possibly contributing to alpha-synuclein aggregation. To this aim, human SH-SY5Y neuroblastoma cells were treated with rotenone and hsc70 mRNA and protein expression were assessed; the effect of rotenone on hsc70 was compared with that exerted by hydrogen peroxide, a generic oxidative stress donor with no inhibitory activity on mitochondrial complex I. Furthermore, the effect of rotenone on hsc70 was verified in primary mouse cortical neurons. The possible contribution of macroautophagy to rotenone-induced hsc70 modulation was explored and the influence of hsc70 gene silencing on neurotoxicity was assessed. We demonstrated that rotenone, but not hydrogen peroxide, induced a significant reduction of hsc70 mRNA and protein expression. We also observed that the toxic effect of rotenone on alpha-synuclein levels was amplified when macroautophagy was inhibited, although rotenone-induced hsc70 reduction was independent from macroautophagy. Finally, we demonstrated that hsc70 gene silencing up-regulated alpha-synuclein mRNA and protein levels without affecting cell viability and without altering rotenone- and hydrogen peroxide-induced cytotoxicity. These findings demonstrate the existence of a novel mechanism of rotenone toxicity mediated by hsc70 and indicate that dysfunction of both CMA and macroautophagy can synergistically exacerbate alpha-synuclein toxicity, suggesting that hsc70 up-regulation may represent a valuable therapeutic strategy for PD.

This chapter is intended to provide an organic revision of evidence for the involvement of autophagy in the pathogenesis of rotenone-induced toxicity. The mechanisms underlying rotenone neurotoxicity are elucidated through a description of findings obtained in both in vivo and in vitro experimental models. Furthermore, this chapter describes the etiological role of rotenone and other pesticide exposure in the pathogenesis of Parkinson’s disease, as demonstrated by epidemiological studies performed in the last decades starting from results obtained in animal and cellular experimental models. The specific focus of the present chapter is to explore the effect of rotenone on autophagic pathway, whose dysfunctions are already recognized to play an important pathogenetic role in Parkinson’s disease. Specifically, a comprehensive revision of the current available literature on the rotenone-induced dysfunctions of the two main types of autophagy, macroautophagy and chaperone-mediated autophagy, is provided in order to clarify the protective rather than detrimental contribute exerted by autophagy alterations in the cell death induced by rotenone.

Parkinson’s disease (PD) is pathologically characterized by the presence of neuronal inclusions known as Lewy bodies, composed primarily of alpha-synuclein (asyn) aggregates. Emerging data indicate that a dysregulation of the autophagic-lysosomal pathway plays a critical pathogenic role in PD, favoring the intraneuronal accumulation of asyn and other neurotoxic proteins. Besides macroautophagy alterations, dysfunctions of chaperone-mediated autophagy (CMA), the main catabolic pathway for asyn, have been reported in post-mortem brain samples obtained from PD patients. To verify the presence of possible systemic alterations of CMA mirroring those observed in diseased brain areas, the expression of CMA effectors (lamp2A e hsc70) and substrates (asyn and MEF2D) was evaluated in peripheral blood mononuclear cells (PBMC) from PD patients and compared to healthy and neurological controls. Similar analyses are ongoing in fibroblast cell lines obtained from sporadic and familial (LRRK2 and SNCA mutant) PD patients obtained from the “Parkinson Institute Biobank” (Milan, http://www.parkinsonbiobank.com/). Results from this study will allow the identification of new possible PD biomarkers useful for early diagnosis, personalized therapy and monitoring of drug efficacy in clinical trials.