50 research outputs found
Exploratory analysis of the association between total T2 lesion volume on brain MRI and resilience in young Patients with Multiple Sclerosis
No full textINTRODUCTION: Multiple Sclerosis is a neurological disorder that affects mostly young adults potentially causing disability due to involvement of motor, sensory, visual and cognitive functions. Frequently patients with multiple sclerosis presents psychological symptoms such as depression and anxiety. Receiving a diagnosis of multiple sclerosis, especially when it happens during young age, represent a challenge for which each individual must face relevant emotional distress. The way in which each person copes to disease seems to be strongly related with resilience. Determinants of resilience include a host of biological, psychological, social, and cultural factors that interact with one another to determine how one respond to stressful experiences. The links between disease-specific variables at diagnosis, resilience, and psychological adjustment of multiple sclerosis patients remain largely unexplored, especially in young adults. AIM OF THE STUDY: to explore the hypothesis that psychological adaptation to multiple sclerosis might be driven not only from personal, social and cognitive factors but also from mechanisms that are intrinsic to the disease process. The primary endpoint of the study was to analyze the correlation between psychological resilience and total T2 lesion volume on brain MRI – i.e. a reliable biomarker of disease severity – in a cohort of young patients newly diagnosed with multiple sclerosis. MATERIALS AND METHODS: we identified eligible patients from an ongoing observational study at University of Verona in which several clinical, psychological, MRI and laboratory measures are collected cross - sectionally in patients with multiple sclerosis aged 18-45 years at enrolment, which occurs in the first two years after diagnosis according to inclusion criteria. For MRI segmentation and lesion volume calculation we used the brain MRI scans obtained from routine investigation for diagnosis or clinical assessment (1.5 or 3 T depending on the machine available at the Center where diagnosis was formulated) within 6 months prior and one month after enrolment. The analysis of total T2 lesion volume (TLV) was made using software open-source ITK-SNAP with semiautomatic segmentation. In order to measure resilience, the Connor-Davidson Resilience Scale (CD – RISC25) was used. The statistical analysis included a descriptive analysis of demographical, psychological and clinical characteristics of participants. A non-parametric approach was applied to compare groups, by using the Kruskal-Wallis test. An explorative correlation analysis was conducted to check possible relationship among variables. RESULTS: our sample consists of 51 consecutive patients, 33 females and 18 males with a mean age of 33.3 years. 88,23% of patients have relapsing-remitting multiple sclerosis and 74,5% a low level of disability (EDSS ≤ 2). The mean T2 lesion volume found was 4.32 cm3 (range 0,21 – 24,79). For resilience (the maximum score on the CD-RISC is 100), the mean value in our sample resulted 65,13 (CI 60,65 – 69,61). Considering data about Quality of Life using the MSQoL- 54 scale, the mean score for physical health resulted 61,48 (CI 58.87 – 64.08) while the mean score for mental health resulted 51,13 (CI 48,22 – 54,03). Other two single scores were calculated; the mean for change in health was 50,19 (CI 45,24 – 55,14); for sexual satisfaction it was 76,73 (CI 70,71 – 82,75). Correlation analysis did not show a significant correlation between T2 total lesion volume and resilience. Despite none of the performed correlation analyses showed statistically significant results, a moderate correlation between resilience and age and between resilience and time from onset of symptoms was numerically observed; a weak inverse correlation was found between EDSS score and resilience. In addition, there was a numerical correlation between resilience and the physical health subscore of MSQoL-54, particularly in the relapsing-remitting multiple sclerosis patients subgroup. CONCLUSION: with reference to the primary outcome, the exploratory analysis we performed in our study showed that total T2 lesion volume on brain MRI of young patients with multiple sclerosis is not significantly associated with resilience. Overall, no significant findings were observed for any of analyzed variables, however some of association examined are worthy of attention. The time that took place between onset of disease and enrollment seems to have a potential moderate correlation with resilience. Among sociodemographic data we have found a possible moderate correlation between resilience and age and also with physical health score in the MSQoL. Also the score regarding physical health on MSQoL numerically shows a moderate correlation with resilience. Our findings show that resilience of young patients with multiple sclerosis, although not statistically associated with disease burden assessed as T2 lesion load on brain MRI, is possibly connected to demographic variables, physical wellbeing, disease duration and possibly disability accumulation in the early stages of the disease. Therefore, all these features deserve to be furtherly examined as possible determinants of resilience, with the ultimate goal of improving quality of life of people with multiple sclerosis
Numerical procedures for the analysis of collapse mechanisms of masonry structures using discrete element modelling
No full textEarthquake damage in historic masonry buildings is generally caused by the collapse of individual portions that become detached form the structure and fail by overturning. These mechanisms are mainly governed by the discrete nature and geometry of the block units. Analyses based on explicit micro-modelling in which each block is considered separately are therefore of increasing importance. This paper offers a robust tool for the seismic assessment of masonry structures under either, quasi-static or dynamic loading. Algorithms for performing dynamic pulses and pushover analyses through the Discrete Element Method are developed and described, taking into account the actual discrete nature and geometry of masonry. A numerical procedure is proposed that automatically detects the collapse mode and follows the evolution of the analysis until collapse. The implemented method is able to give a reliable estimate of the expected failure mechanism, providing the seismic acceleration required to trigger the motion and the ultimate displacement beyond which the collapse occurs. Finally, the implemented algorithms are applied to two case studies and the results are compared with the traditional analysis based on rigid-block kinematics to outline the features and potentialities of the proposed approach
Brain Volume Measures in Adults with MOG-Antibody-Associated Disease: A Longitudinal Multicenter Study
No full textBackground/Objectives: Little is known about the impact of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) on brain atrophy. This multicenter longitudinal study compares brain MRI volumes and T2 lesion volume between MOGAD patients, relapsing-remitting MS (RRMS) patients and a healthy control (HC) group with brain MRI scans available from an online repository. Methods: In total, 16 adult MOGAD patients (9 F) were age- and sex-matched with 44 RRMS patients (17 F) recruited in Verona MS Center and 14 HC subjects. The availability of two brain MRI scans performed 18 ± 6 months apart was mandatory for each patient. Annual percentage brain volume change (PBVC/y), baseline global brain, white matter (WM), gray matter (GM) regional brain volumes and T2 lesion volume were compared between groups. Results: PBVC/y was lower in MOGAD than in RRMS patients (p = 0.014) and lower in HC subjects than in MS patients (p = 0.005). Overall, MOGAD showed higher mean global brain (p = 0.012) and WM volume (p = 0.024) but lower median T2 lesion volume at timepoint 1 (p < 0.001); T2 lesion volume increased over time in the RRMS (p < 0.001) but not in the MOGAD cohort (p = 0.262). Conclusions: The structural brain MRI features of MOGAD show higher global brain and WM volumes and lower brain volume loss over time compared to RRMS, suggesting different underlining pathogenetic mechanisms
Distinct Element Method Analyses for Damage Assessment: The Case of the Valverde Bulwark in the Venetian Fortress of Bergamo
No full textThe 16th-century Venetian Fortress of Bergamo is a complex defensive system over 5 km long with more than 70,000 m2 of masonry wall facing, inscribed to the UNESCO world heritage list in 2017. Today, the first causes of its deterioration are the vegetation growth and the lack of maintenance that have led to instabilities and local failures, particularly in the north-west portion. Thus, in 2019 and 2020, survey campaigns were carried out to assess the safety of one of the most damaged sections, the Valverde bulwark. The survey combines on-site observations, laboratory tests, and photogrammetric and laser scanner surveys to describe the state of the bulwark.
Some numerical simulations have been performed within a Distinct Element Approach (DEM). DEM has been conceived for geo-mechanical analysis, such as caves or mines; however, several researchers have widely proven its application to masonry structures. It assimilates the masonry to a system of discrete bodies consisting of blocks (usually rigid) interacting on their interfaces. DEM analyses are usually executed on simplified models, rarely considering the actual geometry of the masonry structure due to the extremely time-consuming and the usual lack of information. Within the research, a routine dedicated to defining a real-like geometrical model has been developed. The numerical analyses were run to understand the condition of the Valverde bulwark in the actual state, analysing the conditions under self-weight and earth pressure and the behaviour under seismic loading. Through the detailed survey and its automatic digitisation, it is possible to fully recognise and analyse the state of health of these historical structures as well as their mechanical behaviour
Distinct element modelling of masonry walls under out-of-plane seismic loading
No full textThe out-of-plane vulnerability of masonry walls plays a crucial role in the seismic response of existing structures. Depending upon mechanical properties and section morphology, collapse may occur by the onset of a mechanism or, as historic constructions often exhibit, leaf separation, disaggregation or sliding. In these latter cases, structural analyses based on rigid-body mechanics, may overestimate the seismic capacity. The distinct element method (DEM), which represents masonry as an assembly of discrete blocks and nonlinear interfaces, could instead be used. Nevertheless, it is more complex and requires more input parameters, so it is still barely applied in engineering practice. In this paper, the seismic out-of-plane response of masonry walls was modelled with DEM. A shake table test on a two-leaf rubble stone masonry wall and a single-leaf wall in tuff blocks was simulated through nonlinear dynamic analyses. The mechanical properties of joints were calibrated on the basis of dynamic identification under low intensity white noise input, leading to a good prediction of the seismic response. Then, they were further tuned based on surveyed crack pattern for an improved matching between experimental results and numerical postdictions. Finally, the results provided by limit analysis were discussed in the light of DEM simulations
Physical disability and cognitive impairment evolution in benign multiple sclerosis: a five years prospective study
No full textBackground. Benign multiple sclerosis (BMS) definition is generally based on a minimum disease duration (DD) during which a maximum expanded disability status scale (EDSS) score is reached. However, EDSS does not account sufficiently for cognitive deficits, which may be as disabling as motor impairment
Objectives. To study prospectively the evolution of physical disability and cognitive performance of BMS patients
Methods. Among 300 patients seen at Verona MS Center between January and June 2008, 36 patients with relapsing-remitting (RR) course, DD ≥10 years, and EDSS score ≤2.0 were defined BMS cases. Of these, 24 gave consent for inclusion in the study along with 13 sex- and age-matched non-benign MS (n-BMS) patients with RR course, DD≥10 years and EDSS score from 2.5 to 4.5. The two groups were followed for 5 years with neurological examination at least every year and neuropsychological assessment at baseline and at study conclusion. Conventional MRI analysis was done for patients who had a brain scan with the same protocol in 2008 and 2013.
Results. At inclusion BMS subjects were 41±8 years old (mean±standard deviation) with median DD of 15 years (range 11-29) and median EDSS score 1.5 (range 0-2), while n-BMS patients were 46±8 years old, had median DD of 16 years (range 10-27) and median EDSS score 3.0 (range 2.5-4.5). At baseline 16% of patients in both groups failed two or more neuropsychological tests. After 5 years, 23 BMS and 12 n-BMS patients had completed the study. The EDSS score worsened in 8% and 46% of cases, respectively (p=0.008), while the proportion of patients with ≥2 failed neuropsychological tests at 5 years increased at 25% in both groups. BMS and n-BMS patients who failed ≥2 tests had a significantly worse work and financial status both at baseline and at 5 years follow-up even after excluding subjects with EDSS score >3.5. Brain MRI T2 lesion location and number increase over time were not significantly associated with neurological and cognitive outcomes.
Conclusions. Patients classified as having BMS according to widely used criteria had better physical disability outcome at 5 years compared to n-BMS cases. However, rates of initial cognitive impairment and neuropsychological decline over time did not differ between the two groups, including the possible impact on work and social functioning. Neuropsychological testing is essential even in MS patients with minimal or no physical disability given the distinct trajectories followed by disease progression in cognitive and motor domains
Resting-state functional connectivity in multiple sclerosis patients receiving nabiximols for spasticity
No full textAbstract Background Nabiximols (Sativex®) is a cannabinoid approved for multiple sclerosis (MS)-related spasticity. Its mechanism of action is partially understood, and efficacy is variable. Objective To conduct an exploratory analysis of brain networks connectivity changes on resting state (RS) functional MRI (fMRI) of MS patients treated with nabiximols. Methods We identified a group of MS patients treated with Sativex® at Verona University Hospital, who underwent RS brain fMRI in the 4 weeks before (T0) and 4–8 weeks after (T1) treatment start. Sativex® response was defined as ≥ 20% spasticity Numerical Rating Scale score reduction at T1 vs. T0. Connectivity changes on fMRI were compared between T0 and T1 in the whole group and according to response status. ROI-to-ROI and seed-to-voxel connectivity were evaluated. Results Twelve MS patients (7 males) were eligible for the study. Seven patients (58.3%) resulted Sativex® responders at T1. On fMRI analysis, Sativex® exposure was associated with global brain connectivity increase (particularly in responders), decreased connectivity of motor areas, and bidirectional connectivity changes of the left cerebellum with a number of cortical areas. Conclusions Nabiximols administration is associated with brain connectivity increase of MS patients with spasticity. Modulation of sensorimotor cortical areas and cerebellum connectivity could play a role in nabiximols effect
Two sisters with leukoencephalopathy, hearing loss and retinopathy: a familial case of Susac's syndrome?
No full textN.A
Insights for fostering resilience in young adults with multiple sclerosis in the aftermath of the COVID-19 emergency: an Italian survey
No full textObjective: Recent evidence has demonstrated that the COVID-19 pandemic is taking a toll on the mental health of the general population. The psychological consequences might be even more severe for patients with special healthcare needs and psychological vulnerabilities due to chronic diseases, such as multiple sclerosis (MS). Thus, we aimed to explore the psychological impact of this pandemic and of the subsequent healthcare service changes on young adults with MS living in Italy and to examine their coping strategies and preferences regarding psychological support in the aftermath of the pandemic. Methods: Data were collected using a cross-sectional, web-based survey advertised on social networks. We report both quantitative (descriptive statistics, t-tests, and one-way ANOVA) and qualitative data (inductive content analysis). Results: Two hundred and forty-seven respondents (mean age 32 ± 7 years), mainly with relapsing-remitting MS, from all Italian regions participated. Participants felt more worried, confused, sad, and vulnerable because of the disease "during" the pandemic in comparison to their self-evaluation of the period "before" the COVID-19 outbreak. Similarly, their perception of control over MS decreased "during" the pandemic in comparison to the retrospective evaluation of the period "before" the COVID-19 outbreak (p < 0.01). Canceled/postponed visits/exams were listed as the most frequent MS management changes, with modified/postponed pharmacological treatment representing the most stressful change. Psychological support in dealing with pandemic-related fears and improving MS acceptance and well-being was considered extremely important by almost 40% of the respondents. Different coping strategies were mentioned in the qualitative section of the survey, with social support, hobbies, and keeping busy being the most frequent ones. Conclusions: Considering the enormous impact of the pandemic on young adults with MS, we urge MS clinical centers to implement psychological support programs that address the potentially long-lasting psychological negative impact, thus fostering the therapeutic alliance that is being threatened by the infection prevention measures imposed during the pandemic, and promoting psychological resources for adaptively managing future waves of COVID-19
A geometric approach to evaluate the safety of masonry constructions: the case study of St. Scolastica Abbey in Subiaco
No full textThe paper presents the structural assessment of the neoclassical Church at the Abbey of St. Scholastica in Subiaco, located close to Rome, Italy. Here the Renaissance and gothic layers, along with the neoclassical reconstructions from 1769, are uncovered to study their role in the overall stability of the structure. With the aid of historic references, on-site visual inspection and a laser-scanning survey conducted, an understanding of the geometrical and structural configuration that defines this historic construction was established. Adopting an assessment methodology based on limit analysis and graphic statics, the structural evaluation was conducted for each of the individual structural elements i.e., by isolating the arches, vaults, buttresses, and for the integrated system as a whole. Through this analysis, the Geometric Factor of Safety (GFS) related to the global equilibrium of the church's section was calculated. Without any claim of comprehensiveness in the case study, this work stands as a paradigmatic example for people intending to check the stability of historical buildings. In fact, the purpose of the research is to present, through a case study and with the aid of limit analysis approach, how the use of GFS can characterise the degree of safety in a simple and straightforward manner
