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Undifferentiated connective tissue disease: the diagnoses critically revised-experience of a single center
No full textAlthough anti-nuclear antibodies (ANA) are considered the main entry criteria for a diagnosis of undifferentiated connective tissue disease (UCTD), many patients show different rate of ANA positivity and questionable diagnoses. Aim of the study was to revise the UCTD diagnoses and analyse the main predictors of evolution in a monocentric cohort. We retrospectively revised the diagnoses of 331 ANA positive patients, with at least one year of follow-up, classified as UCTD from 2009 and 2017. The diagnosis of UCTD was confirmed in 180 cases (54.4%). The evolution occurred in 18% of cases, after a follow-up of 6.9 (SD: 4.4) years. Raynaud's phenomenon (RP) (OR: 2.39), puffy hands (OR: 6.3), anti-ENA (OR: 2.34), anti-Topoisomerase I antibodies (OR: 4.93), rheumatoid factor (RF) (OR: 2.86) were associated with evolution. Evolution in Systemic Lupus Erythematosus (SLE) occurred in 5 patients (2.78%) and associated with the addition of new autoantibodies, compared with other evolutions (p: 0.034; OR: 12; 95CI: 1.4-103.4). Evolution in Systemic Sclerosis and pSS was found in 14 (7.8%) and 8 cases (4.4%), respectively. Puffy hands and RF positivity as the predictors of SSc and pSS evolution, respectively. A confirmed diagnosis of UCTD, according with the available criteria, was assessed in about a half patients. The occurrence of puffy hands since the onset defines a patient with a potential evolution into SSc, while the addition of new specific autoantibodies represents a typical "fingerprint" of patients developing SLE. Trial registration: Studio ANACTD np 1318
Devices, Techniques, and Algorithms for the Analysis of Dynamic Processes by means of Multivariable Motion Sensors
No full textQuesta tesi introduce dispositivi, tecniche e algoritmi innovativi progettati per l'analisi delle grandezze cinematiche di componenti meccanici appartenenti a processi industriali e a macchinari, mediante l’utilizzo di sensori di moto multivariabile. La ricerca oggetto della tesi si articola in tre attività: lo sviluppo di un algoritmo per la stima accurata della velocità mediante un sensore di moto multivariabile, lo sviluppo di tecniche di autodiagnosi e autocompensazione per sensori di spostamento potenziometrici resistivi, e la stima delle coordinate spaziali di un braccio di un escavatore mediante l’opportuna installazione di un sensore di moto multivariabile e la successiva elaborazione dei segnali forniti.
Dopo l’introduzione al lavoro di ricerca presentata nel primo capitolo, il secondo capitolo della tesi affronta la stima della velocità realizzata mediante l’utilizzo di un sensore di moto multivariabile, che in particolare è in grado di trasdurre simultaneamente sia la posizione che l'accelerazione lineare del componente meccanico a cui è connesso. I segnali di posizione e accelerazione trasdotti sono elaborati da un innovativo algoritmo di stima della velocità sviluppato con l'obiettivo di affrontare i limiti delle tecniche comunemente utilizzate in ambito industriale. L’efficacia dell’algoritmo proposto è stata valutata sperimentalmente sia in termini di errore di stima sia dal tempo computazionale richiesto. In aggiunta, le prestazioni ottenute sono state confrontate con quelle ottenute attraverso altri metodi di stima della velocità presenti in letteratura. I risultati ottenuti convalidano l’efficacia dell’algoritmo proposto.
Il terzo capitolo della tesi riguarda le tecniche di autodiagnosi e autocompensazione proposte per un generico sensore di posizione potenziometrico resistivo. Tali tecniche si basano sulla modellizzazione del sensore mediante due parametri: la resistenza di contatto tra il cursore mobile e la pista resistiva, e la resistenza per unità di lunghezza della pista resistiva. Questi parametri sono utilizzati per rilevare guasti e malfunzionamenti del sensore relativi ad usura, danneggiamento e invecchiamento. Al fine di ricavare informazioni sulle condizioni operative correnti del sensore è stato proposto un metodo per la stima continua dei parametri del modello che non richiede né lo scollegamento del sensore dal processo, né la conoscenza della posizione del cursore. Il rilevamento di un guasto si basa sulla definizione di soglie di allarme per entrambi i parametri del modello. I guasti sono rilevati confrontando le stime attuali dei parametri con i rispettivi valori iniziali, associati al sensore integro, segnalando una condizione di guasto qualora si riscontrino delle deviazioni significative. È inoltre proposto un metodo di autocompensazione che mira a ridurre l'impatto del deterioramento delle condizioni del sensore sull’accuratezza della misura di posizione. La validazione sperimentale delle tecniche proposte è stata condotta utilizzando un sensore sottoposto ad una condizione di usura nota. I risultati sperimentali dimostrano come le tecniche proposte rilevano efficacemente i guasti e riducono l'errore di stima della posizione.
Il quarto capitolo della tesi prevede l'utilizzo di un sensore di moto multivariabile per la stima delle coordinate spaziali relative al braccio di un escavatore su cui il sensore è installato. La stima di tali coordinate è realizzata a partire dall’elaborazione delle molteplici grandezze fisiche che il sensore è in grado di trasdurre: la posizione lineare e gli angoli di Eulero. L’elaborazione di questi dati si basa sulla cinematica della struttura dell’escavatore unitamente alle informazioni meccaniche relative all’installazione del sensore.
Infine, nel quinto capitolo le conclusioni danno evidenza del contributo apportato dall’attività al contesto della sensoristica per grandezze cinematiche.This thesis introduces devices, techniques and innovative algorithms designed for the analysis of kinematic quantities of mechanical components belonging to industrial processes and machinery using multivariable motion sensors. The research covered by this thesis consists of three activities: the development of an algorithm for the accurate velocity estimation using a multivariable motion sensor, the development of self-diagnostic and self-compensation techniques for resistive potentiometric displacement sensors, and the estimation of the spatial coordinates of an excavator arm by the appropriate installation of a multivariable motion sensor and the subsequent processing of the signals provided.
Following the introduction to the research work presented in the first chapter, the second chapter of the thesis addresses the estimation of velocity achieved through the use of a multivariable motion sensor, which in particular is capable of simultaneously transducing both position and linear acceleration of the mechanical component to which it is connected. The transduced position and acceleration signals are processed by an innovative velocity estimation algorithm developed with the aim of addressing the limitations of techniques commonly used in the industrial field. The effectiveness of the proposed algorithm has been experimentally evaluated both in terms of estimation error and computational time required. In addition, the performance obtained has been compared with that obtained through other velocity estimation methods existing in the literature. The results obtained validate the effectiveness of the proposed algorithm.
The third chapter of this thesis presents the self-diagnostic and self-compensation techniques proposed for a generic resistive potentiometric displacement sensor. These techniques are based on modeling the sensor using two parameters: the contact resistance between the sliding cursor and the resistive track, and the resistance per unit length of the resistive track. These parameters are used to detect sensor failures related to wear, damage and aging. In order to derive information about current sensor operating conditions, a method for the continuous estimation of model parameters has been proposed that requires neither disconnecting the sensor from the process nor knowledge of the cursor position. Fault detection is based on the definition of alarm thresholds for both model parameters. Faults are detected by comparing current parameter estimations with their respective initial values, associated with the undamaged sensor, identifying a fault condition if significant deviations are found. A self-compensation method is proposed to reduce the impact of deteriorating sensor conditions on the accuracy of the position measurement. The proposed techniques have been experimentally tested using a sensor subjected to a known wear condition. The experimental results show that the proposed techniques effectively detect faults and reduce the position estimation error.
The fourth chapter of this thesis involves the use of a multivariable motion sensor to estimate spatial coordinates relative to an excavator arm on which the sensor is installed. The estimation of these coordinates is accomplished from the processing of the multiple physical quantities that the sensor is capable of transducing, i.e. linear position and Euler angles. The processing of these data is based on the kinematics of the excavator structure together with mechanical information about the sensor installation.
Finally, in the fifth chapter, the conclusions give evidence of the contribution brought by the activity to the context of kinematic quantities sensing
Clarkson disease in critically and non-critically ill patients: insights from the Italian IRIS-CLS registry
No full textIdiopathic Systemic Capillary Leak Syndrome (ISCLS) is a poorly understood paroxysmal permeability disorder. This study aimed to characterize the clinical features and severity markers of ISCLS in critically and non-critically ill patients. We analyzed prospectively and retrospectively collected data on ISCLS cases from the Italian IRIS-CLS Registry (January 1995-December 2023). A total of 124 acute episodes were identified in 32 patients; 61 episodes in 26 patients having complete records were included in the analysis. Monoclonal gammopathy was found in 20/23 adults but was absent in all three pediatric patients, who exhibited IgA deficiency instead. At admission, patients presented with hypotension (systolic arterial pressure 87 mmHg [80-105]), tachycardia (110 bpm [96-130]), and hemoconcentration (hematocrit 57% [48-62.7]). ICU admission was required in 70.5%, and cardiac involvement occurred in 49.2% of episodes. Fluid volume infused correlated positively with rhabdomyolysis severity, and the need for renal replacement therapy was more frequent in patients receiving >= 3 L. No pharmacologic treatment was effective during the crises. Mortality was 9.8% per episode, and the day-1 Sequential Organ Failure Assessment score was a predictor of death (p = 0.0181). Immunoglobulin prophylaxis reduced attack frequency from 0.67 (0.4-1.07) to 0.4 (0.1-0.52) per year (p = 0.033). Two adults (8.7%) developed multiple myeloma during follow-up. This study provides a comprehensive overview of ISCLS in both critically and non-critically ill patients. We highlight clinical-biochemical-instrumental red-flags and emphasize the need for increased awareness and early recognition since effective treatments for acute shock remain elusive
Fabrication of 3D soft polymeric constructs at high structural integrity through bioprinting optimization of suspended hydrogels
Full text linkThermophysical characterisation of innovative working fluids for closed thermodynamic cycles.
Full text linkQuesta ricerca si focalizza sulla caratterizzazione termofisica di fluidi di lavoro innovativi, destinati ad operare in cicli termodinamici chiusi ad alte temperature. L’identificazione, e lo studio, di fluidi di lavoro puri e/od in miscela innovativi è mirata al miglioramento delle prestazioni di cicli termodinamici per la produzione di energia elettrica e termica. Lo studio si colloca nell'ambito della decarbonizzazione dei settori industriale ed energetico, esplorando il potenziamento di tecnologie chiave come i cicli Rankine a fluido organico (ORC), le pompe di calore ad alta temperatura (HTHP) e cicli di potenza innovativi per sistemi a concentrazione solare (CSP), fondamentali per il raggiungimento di questi obiettivi.
In questo contesto, è stato proposto per la prima volta in letteratura il tetracloruro di silicio (SiCl4) come fluido di lavoro per cicli di potenza ad alta temperatura. Rispetto ai fluidi ORC convenzionali, limitati dalla stabilità termica ad operare a temperature massime intorno a 300°C, il SiCl4 è in grado di mantenere stabilità termochimica oltre 650°C, aprendo nuove possibilità per il recupero di calore da fonti come i gas esausti industriali ad alta temperatura e per l’efficientamento di centrali a biomassa o solari.
In parallelo, il fluorobenzene è stato proposto come fluido innovativo sia per cicli ORC e HTHP. Test di stabilità termica evidenziano un tasso di degradazione del fluorobenzene entro il 5% annuo ad una temperatura di 350°C, posizionandosi tra i pochi fluidi organici termicamente stabili oltre 300°C. Contrariamente al convenzionale test di stabilità termica presso il Laboratorio dei Test dei Fluidi dell’Università degli Studi di Brescia, la metodologia è stata revisionata per simulare la presenza di un sistema di rimozione dei gas non condensabili (NCG).
La caratterizzazione sperimentale dei fluidi di lavoro identificati non si limita al test di stabilità termica, bensì sono state misurate anche proprietà volumetriche dei fluidi. Per questo motivo un’importante parte della ricerca è stata dedicata alla misurazione di dati sperimentali di equilibrio liquido-vapore (VLE) e densità per miscele di CO2 tramite un apparato isocoro sviluppato nel corso di questa ricerca presso il Laboratorio di Test dei Fluidi dell’Università di Brescia. La caratterizzazione volumetrica è stata completata con misure VLE e di densità di CO2+SiCl4 e CO2+C2Cl4, eseguite durante il periodo trascorso presso il Centre for Energy Environment Processes (CEEP) di Mines Paris PSL, in Fontainebleau (Francia).
L’analisi delle miscele a base di CO2 come fluido di lavoro è finalizzata ad esplorarne l’applicabilità in ciclo transcritico per HTHP (intorno 200°C) e per cicli di potenza in impianti a concentrazione solare (CSP) con ricevitore centrale (sopra 550°C). Le proprietà di equilibrio liquido-vapore (VLE) sono state misurate con un apparato PVT a volume variabile, consentendo di calibrare con accuratezza l’equazione di stato ed ottenendo una deviazione media assoluta (AAD%) dello 0.68% rispetto ai dati sperimentali. Dati di densità sono stati misurati tramite un densimetro a tubo vibrante (VTD), che ha permesso di caratterizzare meglio la miscela. Una procedura innovativa ha permesso di ottenere ulteriori punti di bolla (VLE) attraverso il densimetro, i quali erano in accordo con le misure effettuate con l’apparato PVT.
La tesi, strutturata come una raccolta di articoli scientifici organizzati per aree di ricerca, include: Parte 1, dedicata alla caratterizzazione dei fluidi puri per cicli ad alta temperatura; Parte 2, focalizzata sulla sperimentazione delle miscele di CO2; Parte 3, che approfondisce i modelli per la stima delle proprietà di trasporto; e Parte 4, che conclude con analisi sistemiche e valutazioni tecnico-economiche.This research focuses on the thermophysical characterization of innovative working fluids designed to operate in high-temperature closed thermodynamic cycles. The identification and study of novel pure and/or mixed working fluids aim to enhance the performance of thermodynamic cycles for the production of electrical and thermal energy. The study is framed within the context of decarbonizing the industrial and energy sectors, exploring advancements in key technologies such as Organic Rankine Cycles (ORC), high-temperature heat pumps (HTHP), and innovative power cycles for concentrated solar power (CSP) systems, which are essential to achieving these goals.
In this context, silicon tetrachloride (SiCl4) has been proposed for the first time in the literature as a working fluid for high-temperature power cycles. Compared to conventional ORC fluids, which are thermally stable at maximum operating temperatures around 300°C, SiCl4 can maintain thermochemical stability beyond 650°C. This opens new possibilities for heat recovery from sources such as high-temperature industrial exhaust gases and for improving the efficiency of biomass or solar power plants.
In parallel, fluorobenzene has been proposed as an innovative fluid for both ORC and HTHP cycles. Thermal stability tests indicate a degradation rate of fluorobenzene within 5% annually at a temperature of 350°C, positioning it among the few organic fluids thermally stable beyond 300°C. Unlike the conventional thermal stability test conducted at the Fluid Testing Laboratory of the University of Brescia, the methodology was revised to simulate the presence of a system for the removal of non-condensable gases (NCG).
The experimental characterization of the identified working fluids extends beyond thermal stability testing, encompassing volumetric property measurements. For this reason, a significant portion of the research was dedicated to experimental measurements of vapor-liquid equilibrium (VLE) data and densities for CO2 mixtures using an isochoric apparatus developed during this research at the Fluid Testing Laboratory of the University of Brescia. Volumetric characterization was completed with VLE and density measurements of CO2+SiCl4 and CO2+C2Cl4 mixtures, conducted during the research period at the Centre for Energy Environment Processes (CEEP) of Mines Paris PSL, in Fontainebleau, France.
The analysis of CO2-based mixtures as working fluids is aimed at exploring their applicability in transcritical cycles for HTHPs (around 200°C) and for power cycles in concentrated solar power (CSP) plants with central receivers (above 550°C). Vapor-liquid equilibrium (VLE) properties were measured using a variable-volume PVT apparatus, enabling accurate calibration of the equation of state and achieving an absolute average deviation (AAD%) of 0.68% compared to experimental data. Density data were measured using a vibrating-tube densimeter (VTD), which allowed for a more comprehensive characterization of the mixture. An innovative procedure enabled the acquisition of additional bubble points (VLE) through the densimeter, which were consistent with the measurements obtained using the PVT apparatus.
The thesis, structured as a collection of scientific articles organized by research areas, includes: Part 1, dedicated to the characterization of pure fluids for high-temperature cycles; Part 2, focused on the experimental study of CO2 mixtures; Part 3, which delves into models for estimating transport properties; and Part 4, which concludes with system analyses and techno-economic evaluations
Patisiran in ATTRv amyloidosis with polyneuropathy: “PatisiranItaly” multicenter observational study
No full textBackground: Hereditary amyloid transthyretin amyloidosis with polyneuropathy (ATTRv-PN) is a rare, inherited, multisystemic, progressive adult-onset disease, affecting sensorimotor nerves, and various organs. It is caused by mutations in the TTR gene, leading to misfolded monomers that aggregate, forming amyloid fibrils. Patisiran is a small, double-stranded interfering RNA encapsulated in a lipid nanoparticle, designed to enter hepatocytes and selectively target TTR mRNA to reduce both variant TTR and wild-type TTR (wt). This study presents a multicenter, real-life experience of patisiran’s effectiveness and safety in ATTRv-PN. Methods: We enrolled genetically confirmed ATTRv-PN patients from 29 specialized Italian centers. All subjects underwent neurological assessments, including familial amyloid polyneuropathy (FAP) staging, the Neuropathy Impairment Score (NIS), quality-of-life assessment using the Norfolk Quality of Life-Diabetic Neuropathy (Norfolk QOL-DN) questionnaire, and the Compound Autonomic Dysfunction Test (CADT). Additional assessments included baseline and follow-up measures of serum NT-proBNP and interventricular septal thickness. Results: A total of 181 ATTRv patients (69% male) were enrolled. Neurological onset was reported in 60.2% of cases. At baseline, 83.4% of patients exhibited multisystemic involvement, while only 16.6% presented isolated polyneuropathy. For approximately 70% of patients, patisiran was the first treatment; the remainder transitioned from tafamidis or inotersen. Following treatment, most patients demonstrated stabilization of neuropathy progression, regardless of baseline disease severity or genotype. The treatment was well-tolerated, with 90% of patients reporting no adverse events. Conclusion: Patisiran can be considered a valid therapeutic option for the management of patients with ATTRv amyloidosis. Considering its mechanism of action, similar outcomes could also be expected with the wider utilization of newly approved gene silencers for ATTRv therapy, such as vutrisiran
The Changing Impact of Human Cytomegalovirus Serology and Infection on Patient Outcome after Allogeneic Hematopoietic Stem Cell Transplantation: An Italian Prospective Multicenter Survey in the Era of Letermovir Prophylaxis
No full textBackground: In the letermovir primary prophylaxis (LET-PP) era, the epidemiology of human cytomegalovirus infection (HCMV-i) in allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients has changed. Methods: We prospectively evaluated incidence and risk factors for clinically significant (CS) HCMV-i at 180 days from transplant and 1-year overall survival in 1310 allo-HSCTs performed from January 2021 to March 2022 according to LET-PP use. Results: The cumulative incidence of CS-HCMV-i at 100 and 180 days from transplant was 3.8% and 16%, respectively, in patients who received LET-PP, and 14% and 17% in patients who did not. Variables associated with increased risk of CS-HCMV-i in patients who received LET-PP included transplant from an HCMV-seronegative donor, transplant from a donor other than matched related, >20 days to engraftment, and acute graft-versus-host disease (GVHD). Transplant in HCMV-seropositive recipients was associated with increased risk of CS-HCMV-i in patients who did not receive LET-PP. One-year overall survival after transplant was 81.1%. Acute leukemia, disease not in remission at transplant, Eastern Cooperative Oncology Group performance status >1, >20 days to engraftment, acute GVHD, CS Epstein-Barr virus DNAemia, gram-negative bacteremia, and invasive fungal disease were associated with increased mortality in patients who received LET-PP. HCMV recipient seropositivity, Hematopoietic Cell Transplantation Comorbidity Index score ≥3, and gram-negative bacteremia were associated with increased mortality in patients who did not receive LET-PP. Conclusions: In patients who received LET-PP, recipient/donor serology no longer correlates with early CS-HCMV-i whereas it still predicts late CS-HCMV-i as well as risk of CS-HCMV-i in patients who did not receive LET-PP. Donor serology, CS-HCMV-i and HCMV disease no longer impact survival in allo-HSCT recipients who receive LET-PP
Effects of anti-inflammatory therapy in acute heart failure: a systematic review and meta-analysis
No full textWe examined current evidence regarding the effects of anti-inflammatory therapies in patients with acute heart failure (AHF) on the risk of cardiovascular outcomes, inflammatory markers, natriuretic peptides, and renal function. Despite growing evidence that inflammation plays a pivotal role in both the development and progression of heart failure, including AHF, only a few trials have been conducted to date in patients with AHF. A systematic literature search of PubMed, Medline, the Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov was conducted in November 2024 to identify randomized controlled trials (RCTs) evaluating anti-inflammatory therapies in adult patients with AHF. Meta-analyses were conducted to estimate effects on clinical outcomes (death, HF readmission, or worsening HF) and inflammatory and other markers. Five RCTs were identified that enrolled a total of 289 patients to an anti-inflammatory intervention and 273 to a control. Prednisone was examined in two RCTs, anakinra in two, and colchicine in one. Three of the five trials required elevated C-reactive protein (CRP) level for entry. Anti-inflammatory therapy was associated with a reduced risk of the composite outcome (hazard ratio 0.55 [95% CI 0.35–0.86]) and an overall 54% greater reduction in CRP to end of therapy (ratio of geometric mean ratios 0.46 [95% CI 0.29–0.73]), which varied across studies. NT-proBNP and creatinine were not significantly affected. The analysis is limited by the small number of studies but suggests that anti-inflammatory therapy reduces inflammation and may reduce the risk of adverse clinical outcomes in patients with AHF
Disclosure of plasma p-tau217 measure improves diagnostic confidence in patients with Alzheimer's disease versus syndromes associated with frontotemporal lobar degeneration
Full text linkIntroduction: Further research is needed to understand the performance of plasma phosphorylated tau (p-tau)217 in the diagnostic thinking at the individual patient level. We evaluated the incremental diagnostic value of plasma p-tau217, expressed in terms of diagnostic confidence of Alzheimer's disease (DCAD; range 0-100). Methods: Two hundred thirty-two patients with dementia were included and scored in terms of DCAD in a three-step consecutive assessment: (1) clinical work-up, (2) clinical work-up plus plasma p-tau217, and (3) clinical work-up, plasma p-tau217, plus conventional amyloid markers. Two blinded neurologists were asked to review DCAD at each step. Results: DCAD accuracy, expressed as area under the curve, significantly increased from 0.93 with clinical work-up alone, to 0.97 with clinical work-up plus plasma p-tau217 (P = 0.01), with no further increase with the addition of conventional amyloid markers (0.99, P = 0.13). Discussion: Plasma p-tau217 in addition to routine assessment significantly enhances diagnostic confidence that is comparable to well-established amyloidosis biomarkers. Highlights: Plasma phosphorylated tau (p-tau)217 measurements increase diagnostic confidence of Alzheimer's disease. Plasma p-tau217 increases diagnostic confidence comparable to traditional markers. Plasma p-tau217 dosage may be helpful in addition to routine assessment