Modeling of the Acute Toxicity of Benzene Derivatives by Complementary QSAR Methods

A data set containing acute toxicity values (96-h LC50) of 69 substituted benzenes for fathead minnow (Pimephales promelas) was investigated with two Quantitative Structure- Activity Relationship (QSAR) models, either using or not using molecular descriptors, respectively. Recursive Neural Networks (RNN) derive a QSAR by direct treatment of the molecular structure, described through an appropriate graphical tool (variable-size labeled rooted ordered trees) by defining suitable representation rules. The input trees are encoded by an adaptive process able to learn, by tuning its free parameters, from a given set of structureactivity training examples. Owing to the use of a flexible encoding approach, the model is target invariant and does not need a priori definition of molecular descriptors. The results obtained in this study were analyzed together with those of a model based on molecular descriptors, i.e. a Multiple Linear Regression (MLR) model using CROatian MultiRegression selection of descriptors (CROMRsel). The comparison revealed interesting similarities that could lead to the development of a combined approach, exploiting the complementary characteristics of the two approaches

Segmented multifunctional poly(ether ester) polymers containing H-bonding units. Preparation and charactization

A series of poly(ether ester)s containing amide and carbamate groups as H-bonding units and 13-50 mol-% of poly(ethylene glycol) (PEG) segments were prepared by polycondensation in bulk using Ti(OBu)4 as a catalyst. The copolymers were obtained starting from PEG/1,4-butanediol mixtures and a synthetic monomer carrying H-bonding groups. These polymers were designed for biomedical applications, where material biodegradability is required. The influence of the nature of the H-bonding units, the length of the polymethylene spacer between the H-bonding groups and the PEG content on the thermal and solubility properties of the copolymers was investigated. Amide-containing copolymers were more thermally stable than those containing carbamate groups. The PEG content also slightly affected the polymer thermal stability. The DSC traces of all samples presented multiple transitions, whose shape and peak temperature were strongly dependent on the PEG content. Polymer hydrophilicity, surface free energy and equilibrium swelling in phosphate buffer solution (PBS) at 37 °C were mainly influenced by the PEG content, whereas the nature of the H-bonding groups had little effect

Modeling of the acute toxicity of benzene derivatives by complementary QSAR methods

A data set containing acute toxicity values (96-h LC50) of 69 substituted benzenes for fathead minnow (Pimephales promelas) was investigated with two Quantitative Structure- Activity Relationship (QSAR) models, either using or not using molecular descriptors, respectively. Recursive Neural Networks (RNN) derive a QSAR by direct treatment of the molecular structure, described through an appropriate graphical tool (variable-size labeled rooted ordered trees) by defining suitable representation rules. The input trees are encoded by an adaptive process able to learn, by tuning its free parameters, from a given set of structureactivity training examples. Owing to the use of a flexible encoding approach, the model is target invariant and does not need a priori definition of molecular descriptors. The results obtained in this study were analyzed together with those of a model based on molecular descriptors, i.e. a Multiple Linear Regression (MLR) model using CROatian MultiRegression selection of descriptors (CROMRsel). The comparison revealed interesting similarities that could lead to the development of a combined approach, exploiting the complementary characteristics of the two approaches

Fibrin gel: a new scaffold for cardiovascular applications

Aims: Peripheral blood endothelial progenitor cells (EPC) are promising therapies for irreversible myocardial damage, heart failure and peripheral ischemia disease. Natural biopolymers as fibrin are appealing in tissue engineering, because fibrin is biocompatible and bioresorbable. In vitro studies indicate that fibrin can support the growth migration and proliferation of several cells types. Up to date numerous studies have proved the potential of fibrin based injectable cell delivery systems. No studies are available with fibrin as scaffold for EPC. The goal of this study was to investigate if fibrin is a suitable matrix for EPC culture as compared with fibronectin and if different concentrations of fibrinogen (Fb) and thrombin (Th) can influence fibrin structure and EPC behaviour. Methods: Fibrin (Kedrion S.p.a. Lucca, Italy) was prepared mixing Fb (final 4.5-9-18-36 mg/ml) and Th (final 6-12.5-25-50 U/ml). The scaffolds were maintained for 1 hour at 37?C, 5% CO2 before cell seeding. The ultrastructure of fibrin was investigated by scanning electron microscopy (SEM), cryogenic SEM (CRYO-SEM) and atomic force microscopy (AFM) that allow the hydratating analysis of the sample, to evaluate fibre diameter and density. EPC were obtained from peripheral blood of healthy donors and cultured for 1 week on fibrin at the concentration of 1x106 cell/ml in endothelial growth medium. EPC seeded on fibronectin were used as control. Metabolic cell activity on the different scaffolds was assessed after 7 and 14 days by WST1 while cell viability by confocal microscopy (Calcein AM incorporation). Results: Fibrin polymerization rate ranged between 17 and 68 seconds and increased at higher Fb or Th concentrations. Both AFM and SEM analysis revealed a nanometric fibrous structure, with a decrease in fiber diameter with higher fibrinogen concentrations (4.5 mg/ml: 166?4 nm. vs. 36 mg/ml: 119?3 nm, p<0.005, n=5). Different concentrations of Th didn\u27t affect fibre diameter and density. CRYO-SEM suggested a reticulate structure with mesh-size up to 10?m. WST1 assay showed that EPC metabolic activity was better with lower fibrinogen concentrations (4.5 mg/ml: 0.890?0.134 a.u. vs. 36 mg/ml 0.234?0.046 a.u., p<0.05, n=5), while Th had no significant effect. Calcein staining demonstrated that EPC were viable at 14 days and even organised in cluster. Conclusions: Fibrin combines important properties of an ideal biological scaffold, like the nanometric structure, important for the growth and migration of cells. Fibrin is also an ideal scaffold for EPC but the ratio between fibrinogen and thrombin is important for cell viability

Psychological treatments and psychotherapies in the neurorehabilitation of pain. Evidences and recommendations from the italian consensus conference on pain in neurorehabilitation

BACKGROUND: It is increasingly recognized that treating pain is crucial for effective care within neurological rehabilitation in the setting of the neurological rehabilitation. The Italian Consensus Conference on Pain in Neurorehabilitation was constituted with the purpose identifying best practices for us in this context. Along with drug therapies and physical interventions, psychological treatments have been proven to be some of the most valuable tools that can be used within a multidisciplinary approach for fostering a reduction in pain intensity. However, there is a need to elucidate what forms of psychotherapy could be effectively matched with the specific pathologies that are typically addressed by neurorehabilitation teams. OBJECTIVES: To extensively assess the available evidence which supports the use of psychological therapies for pain reduction in neurological diseases. METHODS: A systematic review of the studies evaluating the effect of psychotherapies on pain intensity in neurological disorders was performed through an electronic search using PUBMED, EMBASE, and the Cochrane Database of Systematic Reviews. Based on the level of evidence of the included studies, recommendations were outlined separately for the different conditions. RESULTS: The literature search yielded 2352 results and the final database included 400 articles. The overall strength of the recommendations was medium/low. The different forms of psychological interventions, including Cognitive-Behavioral Therapy, cognitive or behavioral techniques, Mindfulness, hypnosis, Acceptance and Commitment Therapy (ACT), Brief Interpersonal Therapy, virtual reality interventions, various forms of biofeedback and mirror therapy were found to be effective for pain reduction in pathologies such as musculoskeletal pain, fibromyalgia, Complex Regional Pain Syndrome, Central Post-Stroke pain, Phantom Limb Pain, pain secondary to Spinal Cord Injury, multiple sclerosis and other debilitating syndromes, diabetic neuropathy, Medically Unexplained Symptoms, migraine and headache. CONCLUSIONS: Psychological interventions and psychotherapies are safe and effective treatments that can be used within an integrated approach for patients undergoing neurological rehabilitation for pain. The different interventions can be specifically selected depending on the disease being treated. A table of evidence and recommendations from the Italian Consensus Conference on Pain in Neurorehabilitation is also provided in the final part of the pape

From DYMUS to DYPARK: validation of a screening questionnaire for dysphagia in Parkinson's disease

Dysphagia is a common debilitating symptom in people with Parkinson's Disease (PD), adequate screening of swallowing disorders is fundamental. The DYMUS questionnaire has shown very good characteristics for the screening of dysphagia in Multiple Sclerosis, and it might also prove useful for screening dysphagia in PD. The primary aim was to test and validate the DYMUS questionnaire in PD patients. This is an observational multicentric study involving 103 patients affected by PD. All subjects filled in the DYMUS and the Eating Assessment Tool (EAT-10) questionnaires. A subgroup of patients (n = 53) underwent a fiber-optic endoscopic evaluation of swallowing (FEES) and their dysphagia was scored by means of the Dysphagia Outcome Severity Scale (DOSS). DYMUS showed a relatively high level of internal consistency (Cronbach's alpha 0.79). A significant positive correlation was found between the DYMUS and the EAT-10 scores (p &lt; 0.001), while a negative correlation was found between the DYMUS and the DOSS scores (p &lt; 0.001). DYMUS showed a good sensitivity and specificity compared to FEES for detecting dysphagia (area under the curve: 0.82, p &lt; 0.001). The ROC curve analysis showed that a DYMUS score &gt;= 6 represents a reliable cut-off for the risk of dysphagia. The DYMUS questionnaire proved to be a reliable screening tool to detect dysphagia in patients suffering from PD. It is easy to understand, it can be self-administered and therefore adequate for adoption in the clinical practice with the more convenient name of DYPARK

What is the role of the placebo effect for pain relief in neurorehabilitation? Clinical implications from the Italian consensus conference on pain in neurorehabilitation

Background: It is increasingly acknowledged that the outcomes of medical treatments are influenced by the context of the clinical encounter through the mechanisms of the placebo effect. The phenomenon of placebo analgesia might be exploited to maximize the efficacy of neurorehabilitation treatments. Since its intensity varies across neurological disorders, the Italian Consensus Conference on Pain in Neurorehabilitation (ICCP) summarized the studies on this field to provide guidance on its use. Methods: A review of the existing reviews and meta-analyses was performed to assess the magnitude of the placebo effect in disorders that may undergo neurorehabilitation treatment. The search was performed on Pubmed using placebo, pain, and the names of neurological disorders as keywords. Methodological quality was assessed using a pre-existing checklist. Data about the magnitude of the placebo effect were extracted from the included reviews and were commented in a narrative form. Results: 11 articles were included in this review. Placebo treatments showed weak effects in central neuropathic pain (pain reduction from 0.44 to 0.66 on a 0-10 scale) and moderate effects in postherpetic neuralgia (1.16), in diabetic peripheral neuropathy (1.45), and in pain associated to HIV (1.82). Moderate effects were also found on pain due to fibromyalgia and migraine; only weak short-term effects were found in complex regional pain syndrome. Confounding variables might have influenced these results. Clinical implications: These estimates should be interpreted with caution, but underscore that the placebo effect can be exploited in neurorehabilitation programs. It is not necessary to conceal its use from the patient. Knowledge of placebo mechanisms can be used to shape the doctor-patient relationship, to reduce the use of analgesic drugs and to train the patient to become an active agent of the therapy

COVID-19 Severity in Multiple Sclerosis: Putting Data Into Context

Background and objectives: It is unclear how multiple sclerosis (MS) affects the severity of COVID-19. The aim of this study is to compare COVID-19-related outcomes collected in an Italian cohort of patients with MS with the outcomes expected in the age- and sex-matched Italian population. Methods: Hospitalization, intensive care unit (ICU) admission, and death after COVID-19 diagnosis of 1,362 patients with MS were compared with the age- and sex-matched Italian population in a retrospective observational case-cohort study with population-based control. The observed vs the expected events were compared in the whole MS cohort and in different subgroups (higher risk: Expanded Disability Status Scale [EDSS] score &gt; 3 or at least 1 comorbidity, lower risk: EDSS score ≤ 3 and no comorbidities) by the χ2 test, and the risk excess was quantified by risk ratios (RRs). Results: The risk of severe events was about twice the risk in the age- and sex-matched Italian population: RR = 2.12 for hospitalization (p &lt; 0.001), RR = 2.19 for ICU admission (p &lt; 0.001), and RR = 2.43 for death (p &lt; 0.001). The excess of risk was confined to the higher-risk group (n = 553). In lower-risk patients (n = 809), the rate of events was close to that of the Italian age- and sex-matched population (RR = 1.12 for hospitalization, RR = 1.52 for ICU admission, and RR = 1.19 for death). In the lower-risk group, an increased hospitalization risk was detected in patients on anti-CD20 (RR = 3.03, p = 0.005), whereas a decrease was detected in patients on interferon (0 observed vs 4 expected events, p = 0.04). Discussion: Overall, the MS cohort had a risk of severe events that is twice the risk than the age- and sex-matched Italian population. This excess of risk is mainly explained by the EDSS score and comorbidities, whereas a residual increase of hospitalization risk was observed in patients on anti-CD20 therapies and a decrease in people on interferon

Disease-Modifying Therapies and Coronavirus Disease 2019 Severity in Multiple Sclerosis

Objective: This study was undertaken to assess the impact of immunosuppressive and immunomodulatory therapies on the severity of coronavirus disease 2019 (COVID-19) in people with multiple sclerosis (PwMS). Methods: We retrospectively collected data of PwMS with suspected or confirmed COVID-19. All the patients had complete follow-up to death or recovery. Severe COVID-19 was defined by a 3-level variable: mild disease not requiring hospitalization versus pneumonia or hospitalization versus intensive care unit (ICU) admission or death. We evaluated baseline characteristics and MS therapies associated with severe COVID-19 by multivariate and propensity score (PS)-weighted ordinal logistic models. Sensitivity analyses were run to confirm the results. Results: Of 844 PwMS with suspected (n = 565) or confirmed (n = 279) COVID-19, 13 (1.54%) died; 11 of them were in a progressive MS phase, and 8 were without any therapy. Thirty-eight (4.5%) were admitted to an ICU; 99 (11.7%) had radiologically documented pneumonia; 96 (11.4%) were hospitalized. After adjusting for region, age, sex, progressive MS course, Expanded Disability Status Scale, disease duration, body mass index, comorbidities, and recent methylprednisolone use, therapy with an anti-CD20 agent (ocrelizumab or rituximab) was significantly associated (odds ratio [OR] = 2.37, 95% confidence interval [CI] = 1.18-4.74, p = 0.015) with increased risk of severe COVID-19. Recent use (&lt;1 month) of methylprednisolone was also associated with a worse outcome (OR = 5.24, 95% CI = 2.20-12.53, p = 0.001). Results were confirmed by the PS-weighted analysis and by all the sensitivity analyses. Interpretation: This study showed an acceptable level of safety of therapies with a broad array of mechanisms of action. However, some specific elements of risk emerged. These will need to be considered while the COVID-19 pandemic persists