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Abstract The academic and scientific world in general is increasingly concerned about their inability to determine and ascertain the identity of the writer of a text. More and more often the question arises as to whether a scientific article or work handed in by a student was actually produced by the alleged author of the questioned text. The role of artificial intelligence (AI) is increasingly debated due to its dangers of undeclared use. A current example is undoubtedly the undeclared use of ChatGPT to write a scientific text. The article promotes an AI model-independent redundancy measure to support discrimination between hypotheses on authorship of various multilingual texts written by humans or produced by intelligence media such as ChatGPT. The syntax of texts written by humans tends to differ from that of texts produced by AIs. This difference can be grasped and quantified even with short texts (i.e. 1800 characters). This aspect of length is extremely important, because short texts imply a greater difficulty of analysis to characterize authorship. To meet the efficiency criteria required for the evaluation of forensic evidence, a probabilistic approach is implemented. In particular, to assess the value of the redundancy measure and to offer a consistent classification criterion, a metric called Bayes factor is implemented. The proposed Bayesian probabilistic method represents an original approach in stylometry. Analyses performed over multilingual texts (English and French) covering different scientific and human areas of interest (forensic science and socio-psycho-artistic topics) reveal the feasibility of a successful authorship discrimination with limited misclassification rates. Model performance is satisfactory even with small sample sizes.

The article focuses on a careful description of literature on stylometry and on its potential use in forensic science. The state of the art of stylometry is summarized to illustrate the history and the scientific foundation of this discipline. However, the study conducted reveals that there are still some key unresolved aspects that require a response from the academic world. The paper introduces the readers to those issues that need to be tackled for stylometry to be accepted as a forensic discipline. In particular, a coherent probabilistic procedure to assess the probative value of the results obtained through this methodology is largely absent. This gap should be filled properly by applying criteria recommended by international organizations such as the European Network of Forensic Science Institutes. Solutions do exist and will allow a better integration of stylometry in forensic science, favouring the acceptance of this scientific technical method in judicial proceedings.

Evidence that Huntington's disease (HD) is characterized by impaired cholesterol biosynthesis in the brain has led to strategies to increase its level in the brain of the rapidly progressing R6/2 mouse model, with a positive therapeutic outcome. Here we tested the long-term efficacy of chronic administration of cholesterol to the brain of the slowly progressing zQ175DN knock-in HD mice in preventing (“early treatment”) or reversing (“late treatment”) HD symptoms. To do this we used the most advanced formulation of cholesterol loaded brain-permeable nanoparticles (NPs), termed hybrid-g7-NPs-chol, which were injected intraperitoneally. We show that one cycle of treatment with hybrid-g7-NPs-chol, administered in the presymptomatic (“early treatment”) or symptomatic (“late treatment”) stages is sufficient to normalize cognitive defects up to 5 months, as well as to improve other behavioral and neuropathological parameters. A multiple cycle treatment combining both early and late treatments (“2 cycle treatment”) lasting 6 months generates therapeutic effects for more than 11 months, without severe adverse reactions. Sustained cholesterol delivery to the brain of zQ175DN mice also reduces mutant Huntingtin aggregates in both the striatum and cortex and completely normalizes synaptic communication in the striatal medium spiny neurons compared to saline-treated HD mice. Furthermore, through a meta-analysis of published and current data, we demonstrated the power of hybrid-g7-NPs-chol and other strategies able to increase brain cholesterol biosynthesis, to reverse cognitive decline and counteract the formation of mutant Huntingtin aggregates. These results demonstrate that cholesterol delivery via brain-permeable NPs is a therapeutic option to sustainably reverse HD-related behavioral decline and neuropathological signs over time, highlighting the therapeutic potential of cholesterol-based strategies in HD patients. Data availability: This study does not include data deposited in public repositories. Data are available on request to the corresponding authors.

We generated an iPSC line from a patient with spastic paraplegia type 10 (SPG10) carrying the novel missense variant c.50G > A (p.R17Q) in the N-terminal motor domain of the kinesin family member 5A (KIF5A) gene.This patient-derived in vitro cell model will help to investigate the role of different KIF5A mutations in inducing neurodegeneration in spastic paraplegia and in other KIF5A-related disorders, including Charcot-Marie-Tooth type 2 (CMT2) and amyotrophic lateral sclerosis (ALS).

Abstract Objective This work aims to expand knowledge regarding the genetic spectrum of HSPB1‐related diseases. HSPB1 is a gene encoding heat shock protein 27, and mutations in HSPB1 have been identified as the cause of axonal Charcot–Marie–Tooth (CMT) disease type 2F and distal hereditary motor neuropathy (dHMN). Methods Two patients with axonal sensorimotor neuropathy underwent detailed clinical examinations, neurophysiological studies, and next‐generation sequencing with subsequent bioinformatic prioritization of genetic variants and in silico analysis of the likely causal mutation. Results The HSPB1 p.S135F and p.R136L mutations were identified in homozygosis in the two affected individuals. Both mutations affect the highly conserved alpha‐crystallin domain and have been previously described as the cause of severe CMT2F/dHMN, showing a strictly dominant inheritance pattern. Interpretation Thus, we report for the first time two cases of biallelic HSPB1 p.S135F and p.R136L mutations in two families.

A wide spectrum of neurodegenerative diseases has been associated with pathogenic variants in the PNPLA6 (patatin-like phospholipase domain-containing protein 6) gene, including spastic paraplegia type 39, Gordon—Holmes, Boucher—Neuhauser, Oliver—Mc Farlane, and Laurence—Moon syndromes. These syndromes present variable and overlapping clinical symptoms, encompassing cerebellar ataxia, hypogonadotropic hypogonadism, chorioretinal dystrophy, spastic paraplegia, muscle wasting, peripheral neuropathy, and cognitive impairment. In the present study, we performed a wide genetic screening in 292 patients presenting with ataxia or spastic paraplegia using a probe-based customized gene panel, covering >200 genes associated with spinocerebellar diseases. We identified six novel and four recurrent PNPLA6 gene variants in eight patients (2.7%). Six patients presented an infantile or juvenile onset (age

Friedreich’s ataxia (FRDA) is an autosomal-recessive disorder. Here the authors describe a DRG organoid from patient derived-neurons and co-culture with muscle cells to mimic the disorder in vitro and demonstrate potential correction of the phenotype by CRISPR based editing.

Abstract Objective Biallelic variants in RARS1, encoding the cytoplasmic tRNA synthetase for arginine (ArgRS), cause a hypomyelinating leukodystrophy. This study aimed to investigate clinical, neuroradiological and genetic features of patients with RARS1‐related disease, and to identify possible genotype‐phenotype relationships. Methods We performed a multinational cross‐sectional survey among 20 patients with biallelic RARS1 variants identified by next‐generation sequencing techniques. Clinical data, brain MRI findings and genetic results were analyzed. Additionally, ArgRS activity was measured in fibroblasts of four patients, and translation of long and short ArgRS isoforms was quantified by western blot. Results Clinical presentation ranged from severe (onset in the first 3 months, usually with refractory epilepsy and early brain atrophy), to intermediate (onset in the first year with nystagmus and spasticity), and mild (onset around or after 12 months with minimal cognitive impairment and preserved independent walking). The most frequent RARS1 variant, c.5A>G, led to mild or intermediate phenotypes, whereas truncating variants and variants affecting amino acids close to the ArgRS active centre led to severe phenotypes. ArgRS activity was significantly reduced in three patients with intermediate and severe phenotypes; in a fourth patient with intermediate to severe presentation, we measured normal ArgRS activity, but found translation mainly of the short instead of the long ArgRS isoform. Interpretation Variants in RARS1 impair ArgRS activity and do not only lead to a classic hypomyelination presentation with nystagmus and spasticity, but to a wide spectrum, ranging from severe, early‐onset epileptic encephalopathy with brain atrophy to mild disease with relatively preserved myelination.

Spinocerebellar ataxias type 2 (SCA2) is an autosomal dominant inherited disease caused by expanded trinucleotide repeats (≥32 CAG) within the coding region of ATXN2 gene. Age of disease onset primarily depends on the length of the expanded region. The majority of subjects carrying the mutation remain free of clinical signs for few decades (“pre-symptomatic” stage), but in proximity of disease onset subtle neurophysiological, cognitive, and structural brain imaging changes may occur. Aims of the present study are to determine the time-window in which early clinical and neurodegenerative MRI changes may be identified, and to evaluate the rate of the disease progression in both preclinical and early disease phases. We performed a 1-year longitudinal study in 42 subjects: 14 SCA2 patients (mean age 39 years, disease duration 7 years, SARA score 9 points), 13 presymptomatic SCA2 subjects (preSCA2, mean age 39 years, expected time to disease onset 16 years), and 15 gene-negative healthy controls (mean age 33 years). All participants underwent genetic test, neurological examination, cognitive tests, and brain MRI. Evaluations were repeated at 1-year interval. Baseline MRI evaluations in SCA2 patients showed significant atrophy in cerebellum, brainstem, basal ganglia and cortex compared to controls, while preSCA2 subjects had isolated volume loss in the pons, and cortical thinning in specific frontal and parietal areas, namely rostral-middle-frontal and precuneus. One-year longitudinal follow-up demonstrated, in SCA2 patients, volume reduction in cerebellum, pons, superior cerebellar peduncles, and midbrain, and only in the cerebellum in preSCA2 subjects. No progression in clinical or cognitive measures was observed in preSCA2 subjects. The rate of volume loss in the cerebellum and subcortical regions greatly differed between patients and preSCA2. In conclusion, our pilot study demonstrated that MRI measures are highly sensitive to identify longitudinal structural changes in SCA2 patients, and in preSCA2 up to a decade before expected disease onset. These findings may contribute in the understanding of early neurodegenerative processes and may be useful in future therapeutical trials.

Abstract A variety of pathophysiological mechanisms are implicated in Huntington's disease (HD). Among them, reduced cholesterol biosynthesis has been detected in the HD mouse brain from pre‐symptomatic stages, leading to diminished cholesterol synthesis, particularly in the striatum. In addition, systemic injection of cholesterol‐loaded brain‐permeable nanoparticles ameliorates synaptic and cognitive function in a transgenic mouse model of HD. To identify an appropriate treatment regimen and gain mechanistic insights into the beneficial activity of exogenous cholesterol in the HD brain, we employed osmotic mini‐pumps to infuse three escalating doses of cholesterol directly into the striatum of HD mice in a continuous and rate‐controlled manner. All tested doses prevented cognitive decline, while amelioration of disease‐related motor defects was dose‐dependent. In parallel, we found morphological and functional recovery of synaptic transmission involving both excitatory and inhibitory synapses of striatal medium spiny neurons. The treatment also enhanced endogenous cholesterol biosynthesis and clearance of mutant Huntingtin aggregates. These results indicate that cholesterol infusion to the striatum can exert a dose‐dependent, disease‐modifying effect and may be therapeutically relevant in HD.

Many quarters of forensic science use reporting formats such as “identification,” “inconclusive,” and “exclusion.” These types of conclusions express opinions as to whether or not a particular person or object is the source of the material or traces of unknown source that is of interest in a given case. Rendering an “inconclusive” conclusion is sometimes criticized as being inadequate because—supposedly—it does not provide recipients of expert information with helpful directions. In this paper, we critically examine this claim using decision theory. We present and defend the viewpoint according to which deciding to render an “inconclusive” conclusion is, on a formal account, not as inadequate as may commonly be thought. Using elements of decision theory from existing accounts on the topic, we show that inconclusive conclusions can actually be viable alternatives with respect to other types of conclusions, such as “identification.”

Background: Cerebellar atrophy is a neuroradiological definition that categorizes conditions heterogeneous for clinical findings, disease course, and genetic defect. Most of the papers proposing a diagnostic workup for pediatric ataxias are based on neuroradiology or on the literature and experimental knowledge, with a poor participation of clinics in the process of disease definition. Our study aims to offer a different perspective on the way we approach cerebellar atrophy in developmental age, building a clinical-based diagnostic workup to guide molecular diagnosis. Methods: we recruited 52 patients with pediatric-onset cerebellar atrophy and definite disease categorization. Children underwent brain MRI, neurophysiological exams, metabolic investigations, and muscle biopsy with respiratory chain complex study. Single-gene sequencing, next-generation sequencing NGS panels, whole-exome sequencing (WES), and disease-specific techniques have been used to reach genetic confirmation. Results: Brain MRI is the main method of diagnosis, followed by tests on muscle biopsy and peripheral nervous system study. Other exams (e.g., metabolic investigations or evoked potentials) may be useful to narrow the list of diagnostic possibilities. Conclusions: We propose a diagnostic approach to cerebellar atrophy in children based on clinical findings, and support the evidence that a precise phenotypic definition may lead to the formulation of a definite diagnosis or otherwise guide the back phenotyping process derived from large molecular data.

The rare autosomal dominant Charcot-Marie-Tooth type 2B (CMT2B) is associated with mutations in the RAB7A gene, involved in the late endocytic pathway. CMT2B is characterized by predominant sensory loss, ulceromutilating features, with lesser-to-absent motor deficits. We characterized clinically and genetically a family harboring a novel pathogenic RAB7A variant and performed structural and functional analysis of the mutant protein. A 39-year-old woman presented with early-onset walking difficulties, progressive distal muscle wasting and weakness in lower limbs and only mild sensory signs. Electrophysiology demonstrated an axonal sensorimotor neuropathy. Nerve biopsy showed a chronic axonal neuropathy with moderate loss of all caliber myelinated fibers. Next-generation sequencing (NGS) technology revealed in the proband and in her similarly affected father the novel c.377A>G (p.K126R) heterozygous variant predicted to be deleterious. The mutation affects the biochemical properties of RAB7 GTPase, causes altered interaction with peripherin, and inhibition of neurite outgrowth, as for previously reported CMT2B mutants. However, it also shows differences, particularly in the epidermal growth factor receptor degradation process. Altogether, our findings indicate that this RAB7A variant is pathogenic and widens the phenotypic spectrum of CMT2B to include predominantly motor CMT2. Alteration of the receptor degradation process might explain the different clinical presentations in this family.

Amyotrophic lateral sclerosis (ALS) is an adult-onset progressive neurodegenerative disease due to motor neuron loss variably associated with frontotemporal dementia (FTD). Next generation sequencing technology revealed an increasing number of rare and novel genetic variants and interpretation of their pathogenicity represents a major challange in the diagnosis of ALS. We selected 213 consecutive patients with sporadic or familial (16%) ALS, tested negative for SOD1, FUS, TARDBP, and C9orf72 mutations. To reveal rare forms of genetic ALS, we performed a comprehensive multi-gene panel screening including 46 genes associated with ALS, hereditary motor neuronopathies, spastic paraplegia, and FTD. Our study allowed the identification of pathogenic or likely pathogenic variants in 4.2% of patients. The genes with the highest percentage of pathogenic variants were OPTN (1%), VCP (1%) SQSTM1(1%), SETX (0.4%), FIG4 (0.4%), and GARS1 (0.4%) genes. We also found 49 novel or rare gene variants of unknown significance in 30 patients (14%), 44 unlikely pathogenic variants (39%), and 48 variants in ALS susceptibility genes. The results of our study suggest the screening of OPTN, VCP, and SQSTM1 genes in routine diagnostic investigations for both sporadic and familial cases, and confirm the importance of diagnosis and couselling for patients and their relative family members.

Glutamine Synthetase 1 (GS1) is a key enzyme that catalyzes the ATP-dependent synthesis of l-glutamine from l-glutamate and is also member of the Glutamate Glutamine Cycle, a complex physiological process between glia and neurons that controls glutamate homeostasis and is often found compromised in neurodegenerative diseases including Huntington’s disease (HD). Here we report that the expression of GS1 in neurons ameliorates the motility defects induced by the expression of the mutant Htt, using a Drosophila model for HD. This phenotype is associated with the ability of GS1 to favor the autophagy that we associate with the presence of reduced Htt toxic protein aggregates in neurons expressing mutant Htt. Expression of GS1 prevents the TOR activation and phosphorylation of S6K, a mechanism that we associate with the reduced levels of essential amino acids, particularly of arginine and asparagine important for TOR activation. This study reveals a novel function for GS1 to ameliorate neuronal survival by changing amino acids’ levels that induce a “starvation-like” condition responsible to induce autophagy. The identification of novel targets that inhibit TOR in neurons is of particular interest for the beneficial role that autophagy has in preserving physiological neuronal health and in the mechanisms that eliminate the formation of toxic aggregates in proteinopathies.

Over the past few decades, age estimation of living persons has represented a challenging task for many forensic services worldwide. In general, the process for age estimation includes the observation of the degree of maturity reached by some physical attributes, such as dentition or several ossification centers. The estimated chronological age or the probability that an individual belongs to a meaningful class of ages is then obtained from the observed degree of maturity by means of various statistical methods. Among these methods, those developed in a Bayesian framework offer to users the possibility of coherently dealing with the uncertainty associated with age estimation and of assessing in a transparent and logical way the probability that an examined individual is younger or older than a given age threshold. Recently, a Bayesian network for age estimation has been presented in scientific literature; this kind of probabilistic graphical tool may facilitate the use of the probabilistic approach. Probabilities of interest in the network are assigned by means of transition analysis, a statistical parametric model, which links the chronological age and the degree of maturity by means of specific regression models, such as logit or probit models. Since different regression models can be employed in transition analysis, the aim of this paper is to study the influence of the model in the classification of individuals. The analysis was performed using a dataset related to the ossifications status of the medial clavicular epiphysis and results support that the classification of individuals is not dependent on the choice of the regression model.

When forensic scientists evaluate and report on the probative strength of single DNA traces, they commonly rely on only one number, expressing the rarity of the DNA profile in the population of interest. This is so because the focus is on propositions regarding the source of the recovered trace material, such as ‘the person of interest is the source of the crime stain’. In particular, when the alternative proposition is ‘an unknown person is the source of the crime stain’, one is directed to think about the rarity of the profile. However, in the era of DNA profiling technology capable of producing results from small quantities of trace material (i.e., non-visible staining) that is subject to easy and ubiquitous modes of transfer, the issue of source is becoming less central, to the point that it is often not contested. There is now a shift from the question ‘whose DNA is this?’ to the question ‘how did it get there?’. As a consequence, recipients of expert information are now very much in need of assistance with the evaluation of the meaning and probative strength of DNA profiling results when the competing propositions of interest refer to different activities. This need is widely demonstrated in day-to-day forensic practice and is also voiced in specialized literature. Yet many forensic scientists remain reluctant to assess their results given propositions that relate to different activities. Some scientists consider evaluations beyond the issue of source as being overly speculative, because of the lack of relevant data and knowledge regarding phenomena and mechanisms of transfer, persistence and background of DNA. Similarly, encouragements to deal with these activity issues, expressed in a recently released European guideline on evaluative reporting 42, which highlights the need for rethinking current practice, are sometimes viewed skeptically or are not considered feasible. In this discussion paper, we select and discuss recurrent skeptical views brought to our attention, as well as some of the alternative solutions that have been suggested.

The early growth response 2 (EGR2) transcription factor plays a crucial role in peripheral nerve myelination. Mutations of this gene are associated with a wide variety of demyelinating neuropathies differing from each other in the severity of nerve injury. Although the expression of EGR2 mutants inhibits the transactivation of myelin gene promoters, the exact molecular mechanism by which these mutations cause the alteration of the myelination process is still unknown. Recently, it was reported that EGR2 is directly involved in the transcriptional regulation of Connexin 32, a myelin gene frequently mutated in peripheral neuropathies. Here we describe the differential effect of two EGR2 mutants; while mutant D355V partially induces Cx32 promoter, mutant R381H does not. Furthermore, we show that a sequence located at −216, recognized by the wild-type and the mutant D355V recombinant proteins, is relevant for promoter transactivation.

The altered aggregation of proteins in non-native conformation is associated with endoplasmic reticulum derangements, mitochondrial dysfunction and excessive production of reactive oxygen species. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare hereditary systemic vasculopathy, caused by NOTCH3 mutations within the receptor extracellular domain, that lead to abnormal accumulation of the mutated protein in the vascular wall. NOTCH3 misfolding could cause free radicals increase also in CADASIL. Aim of the study was to verify whether CADASIL patients have increased oxidative stress compared to unrelated healthy controls. We enrolled 15 CADASIL patients and 16 gender- and age-matched healthy controls with comparable cardiovascular risk factor. Blood and plasma reduced and total aminothiols (homocysteine, cysteine, glutathione, cysteinylglycine) were measured by HPLC and plasma 3-nitrotyrosine by ELISA. Only plasma reduced cysteine (Pr-Cys) and blood reduced glutathione (Br-GSH) concentrations differed between groups: in CADASIL patients Br-GSH levels were higher (p = 0.019) and Pr-Cys lower (p = 0.010) than in controls. No correlation was found between Br-GSH and Pr-Cys either in CADASIL patients (rho 0.25, P = 0.36) or in controls (rho -0.15, P = 0.44). Conversely, 3-nitrotyrosine values were similar in CADASIL and healthy subjects (p = 0.82). The high levels of antioxidant molecules and low levels of oxidant mediators found in our CADASIL population might either be expression of an effective protective action against free radical formation at an early stage of clinical symptoms or they could suggest that oxidative stress is not directly involved in the pathogenesis of CADASIL.