This paper presents the analysis carried out for designing and developing a prototype expert system capable of managing the electrical system of an industrial plant. The electric network of the plant, including significant gas turbine and steam turbine generation facilities, is presented. The modeling phase of the system for successive analysis by simulation using a commercial power system code is also reported. The load-shedding problem is then considered and the related engineering aspects are briefly recalled. The guidelines for the realization of a load-shedding scheme for industrial electrical plants based also on advanced artificial intelligence tools such as expert systems are proposed. The expert system is used online to prepare lookup load-shedding tables capable of accounting for actual process conditions. Offline validation of the proposed shedding is then operated by static and/or dynamic simulation. The use of a prototype rule-based expert system is expected to permit the achievement of a better flexibility in the realization of load-shedding schemes for improving the process continuity and management.
Charcot-Marie-Tooth (CMT) patients present mainly lower limbs disability, with slowly progressive distal muscle weakness and atrophy, but hands impairment is a relevant problem affecting the quality of life (QoL). The evaluation of the upper limb is of primary importance. Often these patients present subclinical disorders or report difficulties in manipulating objects, with little evidence in the most used outcome measures. We aim to investigate the impact of hand impairment in the perceived QoL of CMT persons and secondly whether the Disability of Arm, Shoulder and Hand (DASH) scale can be useful in assessing upper limb abilities in CMT. We recruited 23 patients with confirmed genetic diagnosis of CMT. We performed a clinical evaluation with Sollerman Hand Function Test (SHFT), Thumb Opposition Test (TOT) and CMT examination score (CMTES). We completed the clinical assessment with DASH scale and the Short form 36 (SF36) questionnaire for a subjective evaluation of upper limb disability and quality of life. All patients also underwent an instrumental evaluation with a hand-held dynamometer measuring hand grip and tripod pinch and a sensor-engineered glove test (SEGT) to evaluate finger opposition movements in a quantitative spatial-temporal way. As expected, we found significant differences between CMT and control group performances in both clinical and instrumental assessment. Concerning QoL, we found that total score of SF36 and the SF36 Physical Composite Score (PCS) correlate with all clinical and instrumental Outcome Measures (OMs), particularly with Tripod pinch strength and TOT, which are considered major determinants of manual dexterity in CMT. DASH scale correlates with most clinical and instrumental OMs. Not surprisingly, we also found a correlation with DASH work, because CMT affects young patients engaged in work activities. However, we found a low correlation with the TOT and the dynamometer suggesting that DASH may not be the best scale for remote monitoring of upper limb disorders in CMT patients. Nevertheless, the results of our study confirm the usefulness of SF36 in recognizing the impact of upper limb disability in these subjects suggesting its use even in the remote monitoring of physical functioning.
We evaluated 13 patients affected by myasthenia gravis (MG) who had coronavirus disease 2019 (COVID-19) before vaccination and 14 myasthenic patients who contracted severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection after vaccination to evaluate factors related to different COVID-19 outcomes. We compared the two groups' previous stability of MG and the severity of SARS-CoV-2 infection. Vaccinated and non-vaccinated patients were comparable in terms of severity of the previous MG course (mean maximum myasthenia gravis Foundation of America-MGFA-Class III) and during SARS-CoV-2 infection (mean MGFA Class II). In non-vaccinated patients, the hospitalization and severe course percentages were 61.5%, while the mortality reached 30.8%. The hospitalization, severe course, and mortality percentages in vaccinated patients were 7.1%. In deceased, non-vaccinated patients, greater myasthenia severity in the past clinical history, but not at the time of infection, was observed. Similarly, older age at MG onset and at the time of infection correlated with a more severe COVID-19 course in non-vaccinated patients (p = 0.03 and p = 0.04), but not in the group of vaccinated patients. In summary, our data support a protective role of vaccination in myasthenic patients, even if anti-CD20 therapy might be associated with a poor immune response to vaccines.
Recessively inherited limb-girdle muscular dystrophy type 1, caused by mutations in the calpain 3 gene, is the most common limb-girdle muscular dystrophy worldwide. Recently, cases of autosomal dominant calpainopathy have been described. A man was referred to our neurological outpatient clinic at the age of 54 for persistent hyperCKemia (>1000 U/l) associated with muscle fatigue and myalgia. Clinical examination revealed mild proximal weakness in the lower limbs. His brother exhibited a moderate increase in serum creatine kinase levels (up to 2000 U/l) without other signs of myopathy. Their father experienced slowly progressive lower limb weakness after the age of 50. The calpain 3 variant c.1478G>A (p.Arg493Gln) in the heterozygous state was identified in both brothers.
Background The application of massive parallel sequencing technologies in the molecular analysis of Charcot-Marie-Tooth (CMT) has enabled the rapid and cost-effective identification of numerous potentially significant variants for diagnostic purposes. The objective is to reduce the number of variants, focusing only on those with pathogenic significance. The 2015 American College of Medical Genetics and Genomics (ACMG) guidelines aid in achieving this goal, but it is now evident that a pathology or gene-specific review of these rules is essential to avoid misinterpretations that may result from blindly applying the criteria. This study demonstrates how revised ACMG criteria, combined with CMT-specific literature data and expertise, can alter the final classification of a variant. Methods We reviewed ACMG criteria based on current knowledge of CMT and provided suggestions for adapting them to the specificities of CMT. Results Of the 226 index patients analysed, a diagnostic yield of 20% was obtained. It is worth noting that the 9% of cases had their final diagnosis changed with the application of the revised criteria, often resulting in the loss of the pathogenic classification of a variant. Conclusions The widespread availability of high-throughput sequencing technologies has enabled genetic testing even for laboratories without specific disease expertise. Disease-specific ACMG criteria can be a valuable tool to prevent the proliferation of variants of uncertain significance and the misinterpretation of variants.
Nerve biopsy represents the conclusive step in the diagnostic work-up of peripheral neuropathies, and its diagnostic yield is still debated. The aim of this study is to consider the impact of nerve biopsy on reaching a useful diagnosis in different peripheral neuropathies and its changing over time. We retrospectively analyzed 1179 sural nerve biopsies performed in the period 1981-2017 at Neurological Clinic of Policlinico San Martino (Genoa). We relied on medical records and collected both clinical and pathological data in a database. Biopsy provided univocal diagnoses in 53% of cases (with an increase over time), multiple diagnostic options in 14%, while diagnosis was undetermined in 33% (undetermined reports decreased during the years). In 57% of patients, the pre-biopsy suspicion was confirmed, while in 43% sural biopsy modified the clinical diagnosis. The highest yield was in axonal neuropathies (29% undetermined reports versus 40% in demyelinating and 48% in mixed neuropathies). In 68% of patients with vasculitic neuropathy, this etiology was already suspected, whereas in 32% nerve biopsy modified the clinical diagnosis. During the years, the number of annually performed biopsies decreased significantly (p=0.007), with an increase in the mean age of patients (p<0.0001). The percentage of hereditary neuropathies had a significant decrease (p=0.016), while the rate of vasculitic and chronic inflammatory neuropathies increased (p<0.0001). This is the largest Italian study addressing the yield of sural nerve biopsy. During the years, we observed a progressive refinement of the indication of this procedure, which confirms its utility for interstitial neuropathies, particularly if non-systemic vasculitic neuropathy is suspected.
POLR3B gene encodes a subunit of RNA polymerase III (Pol III). Biallelic mutations in POLR3B are associated with leukodystrophies, but recently de novo heterozygous mutations have been described in early onset peripheral demyelinating neuropathies with or without central involvement. Here, we report the first Italian case carrying a de novo variant in POLR3B with a pure neuropathy phenotype and primary axonal involvement of the largest nerve fibers.