Neuralgic Amyotrophy and Hourglass Nerve Constriction/Nerve Torsion: Two Sides of the Same Coin? A Clinical Review

Neuralgic amyotrophy, also called Parsonage-Turner syndrome, in its classic presentation is a brachial plexopathy or a multifocal neuropathy, involving mainly motor nerves of the upper limb with a monophasic course. Recently, a new radiological entity was described, the hourglass constriction, which is characterized by a very focal constriction of a nerve, or part of it, usually associated with nerve thickening proximally and distally to the constriction. Another condition, which is similar from a radiological point of view to hourglass constriction, is nerve torsion. The pathophysiology of neuralgic amyotrophy, hourglass constriction and nerve torsion is still poorly understood, and a generic role of inflammation is proposed for all these conditions. It is now widely accepted that nerve imaging is necessary in identifying hourglass constrictions/nerve torsion pre-surgically in patients with an acute mononeuropathy/plexopathy. Ultrasound and MRI are useful tools for diagnosis, and they are consistent with intraoperative findings. The prognosis is generally favorable after surgery, with a high rate of good motor recovery.

Safety and efficacy of endovascular thrombectomy for primary and secondary MeVO

BACKGROUND

Medium-vessel occlusions (MeVO) are emerging as a new target for endovascular treatment (EVT). Primary MeVO occur de novo, while secondary MeVO arise from large vessel occlusion (LVO) through clot migration or fragmentation - spontaneously, following intravenous thrombolysis or EVT. We aimed to evaluate efficacy and safety of EVT in primary and EVT-induced secondary MeVO.

METHODS

Retrospective single-center study on consecutive EVT-treated acute ischemic stroke, from 2019-to-2021. We considered: (1) exclusive-LVO, patients with LVO and - in case of residual distal occlusion - no rescue endovascular procedure; (2) primary MeVO: initial A2, A3, M2 non-dominant, M3, P2, P3 occlusions; (3) EVT-induced secondary MeVO, presenting LVO with subsequent (treated) EVT-induced MeVO. We compared (univariable/multivariable logistic regression) EVT efficacy (eTICI≥2b, 3-month modified Rankin Scale [mRS] 0-2) and safety (EVT-complications [vessel dissection, perforation, persistent-SAH], symptomatic ICH) in all MeVO versus exclusive-LVO, primary MeVO versus exclusive-LVO, EVT-induced secondary MeVO versus exclusive-LVO and EVT-induced secondary MeVO versus primary MeVO.

RESULTS

We included 335 patients: 221 (66.0 %) exclusive-LVO and 114 (34.0 %) MeVO (55 [48.2 %] primary, 59 [51.8 %] secondary). Compared to exclusive-LVO, primary MeVO had higher rates of EVT complications (aOR 3.77 [95%CI 1.58-9.00],p=0.003), lower rates of eTICI≥2b (aOR 0.32 [95%CI 0.12-0.88],p=0.027) and mRS 0-2 (aOR 0.28 [95%CI 0.13-0.63],p=0.002). EVT-induced secondary MeVO had no major differences in efficacy and safety outcomes compared to exclusive-LVO, but a better mRS 0-2 (aOR 8.00 [95%CI 2.12-30.17],p=0.002) compared to primary MeVO.

CONCLUSIONS

Primary and EVT-induced secondary MeVO showed different safety/efficacy EVT-related profiles. Dedicated randomized data are needed to identify the best acute reperfusion strategy in the two categories.

Reliability of intraoperative visual evoked potentials (iVEPs) in monitoring visual function during endoscopic transsphenoidal surgery

OBJECTIVE

To refine a reliable and reproducible intraoperative visual evoked potentials (iVEPs) monitoring protocol during endoscopic transsphenoidal surgery. To assess the reliability of baseline iVEPs in predicting preoperative visual status and perioperative iVEP variation in predicting postoperative visual outcome.

METHODS

Sixty-four patients harboring tumors of the pituitary region were included. All patients underwent endoscopic endonasal approach (EEA) with iVEPs monitoring, using a totally intravenous anesthetic protocol. Ophthalmological evaluation included visual acuity and visual field studies.

RESULTS

Preoperatively, visual acuity was reduced in 86% and visual field in 76.5% of cases. Baseline iVEPs amplitude was significantly correlated with preoperative visual acuity and visual field (p = 0.001 and p = 0.0004, respectively), confirming the reliability of the neurophysiological/anesthetic protocol implemented. Importantly, perioperatively the variation in iVEPs amplitude was significantly correlated with the changes in visual acuity (p < 0.0001) and visual field (p = 0.0013). ROC analysis confirmed that iVEPs are an accurate predictor of perioperiative visual acuity improvement, with a 100% positive predictive value in patients with preoperative vision loss.

CONCLUSIONS

iVEPs during EEA is highly reliable in describing preoperative visual function and can accurately predict postoperative vision improvement.

SIGNIFICANCE

iVEPs represent a promising resource for carrying out a more effective and safe endoscopic transsphenoidal surgery.

Evaluation of the treatment options for COVID-19 patients using generalized hesitant fuzzy- multi criteria decision making techniques

The breakout of the pandemic COVID-19 has affected numerous countries and territories worldwide. As COVID-19 specific medicines yet to be invented, at present the treatment is case specific, hence identification and evaluation of different prevalent treatment options based on various criteria and attributes are very important not only from the point of view of present pandemic but also for futuristic pandemic preparedness. The present study focuses on identifying, evaluation and ranking of treatment options using Multi Criteria Decision Making (MCDM). In this regard, the existing literature, doctors and scientist were interviewed to know the current treatment options in vogue and the scale of their importance with respect to the criteria. The criteria taken are side effect, regime cost, treatment duration, plasma stability, plasma turnover, time of suppression, ease of application, drug-drug interaction, compliance, fever, pneumonia, intensive care, organ failure, macrophage activation syndrome, hemophagocytic syndrome, pregnancy, kidney problem, age. This study extended Hesitant Fuzzy Set (HFS) to Generalized Hesitant Fuzzy Sets (GHFS). Generalized Hesitant Pentagonal Fuzzy Number (GHPFN) is developed. The properties of GHPFN are demonstrated. Two types of GHPFN has been described. The GHPFN (2nd type) along with MCDM tool Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) has been applied to rank the treatment options. The result of the study ranked 'Hydroxychloroquine' as the first alternative followed by, 'Plasma Exchange', 'Tocilizumab', 'Remdesivir' and 'Favipravir'. To check the robustness and steadiness of the proposed methodology, comparative analysis and sensitivity analysis has been conducted.

Clinical, neurophysiological and serological clues for the diagnosis of neuromyotonia and distinction from cramp-fasciculation syndrome

Neuromyotonia and cramp-fasciculation syndrome diagnosis currently relies on neurophysiological examination. In this study we investigated the clinical features and neural antibody profile of patients with neuromyotonia and cramp-fasciculation syndrome to assess the diagnostic value of serological testing. Available sera from adult patients with electromyography-defined neuromyotonia and cramp-fasciculation syndrome were tested for neural antibodies by indirect immunofluorescence on mouse brain sections and live cell-based assays. Forty patients were included, 14 with neuromyotonia and 26 with cramp-fasciculation syndrome. Neural antibodies were detected in 10/10 neuromyotonia sera, most commonly against contactin-associated protein 2 (7/10, 70%), and in 1/20 (5%) cramp-fasciculation syndrome sera. Clinical myokymia, hyperhidrosis, and paresthesia or neuropathic pain were more common in neuromyotonia and mostly associated with contactin-associated protein 2 antibodies. Central nervous system involvement was present in 4/14 (29%) neuromyotonia patients. A tumor was detected in 13/14 (93%) neuromyotonia patients (thymoma, 13), and in 4/26 (15%) with cramp-fasciculation syndrome (thymoma, 1; other neoplasms, 3). Twenty-one/27 (78%) patients achieved a significant improvement or complete remission. Our findings highlight clinical, neurophysiological and serological clues that can be useful in the diagnosis of neuromyotonia and cramp-fasciculation syndrome. Antibody testing is valuable for neuromyotonia diagnosis, while its usefulness in cramp-fasciculation syndrome confirmation is limited.

Combined treatment of nerve growth factor and transcranical direct current stimulations to improve outcome in children with vegetative state after out-of-hospital cardiac arrest

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) is one of the most dramatic events in pediatric age and, despite advanced neurointensive care, the survival rate remains low. Currently, no effective treatments can restore neuronal loss or produce significant improvement in these patients. Nerve Growth Factor (NGF) is a neurotrophin potentially able to counteract many of the deleterious effects triggered by OHCA. Transcranial Direct Current Stimulation (tDCS) has been reported to be neuroprotective in many neurological diseases, such as motor deficit and cognitive impairment. Children with the diagnosis of chronic vegetative state after OHCA were enrolled. These patients underwent a combined treatment of intranasal administration of human recombinant NGF (hr-NGF), at a total dose of 50 gamma/kg, and tDCS, in which current intensity was increased from zero to 2 mA from the first 5 s of stimulation and maintained constant for 20 min. The treatment schedule was performed twice, at one month distance each. Neuroradiogical evaluation with Positron Emission Tomography scan (PET), Single Photon Emission Computed Tomography (SPECT), Electroencephalography (EEG) and Power Spectral Density of the brain (PSD) was determined before the treatment and one month after the end. Neurological assessment was deepened by using modified Ashworth Scale, Gross Motor Function Measure, and Disability Rating Scale.

RESULTS

Three children with a chronic vegetative state secondary to OHCA were treated. The combined treatment with hr-NGF and tDCS improved functional (PET and SPECT) and electrophysiological (EEG and PSD) assessment. Also clinical conditions improved, mainly for the reduction of spasticity and with the acquisition of voluntary finger movements, improved facial mimicry and reaction to painful stimuli. No side effects were reported.

CONCLUSIONS

These promising preliminary results and the ease of administration of this treatment make it worthwhile to be investigated further, mainly in the early stages from OHCA and in patients with better baseline neurological conditions, in order to explore more thoroughly the benefits of this new approach on neuronal function recovery after OHCA.

Protection and Disinfection Activities of Oregano and Thyme Essential Oils Encapsulated in Poly(ε-caprolactone) Nanocapsules

The biocolonization of building materials by microorganisms is one of the main causes of their degradation. Fungi and bacteria products can have an undesirable impact on human health. The protection and disinfection of sandstone and wood materials are of great interest. In this study, we evaluated the protection and disinfection activity of oregano and thyme essential oils encapsulated in poly(ε-caprolactone) nanocapsules (Or-NCs, Th-NCs) against four types of environmental microorganisms: Pleurotus eryngii, Purpureocillium lilacinum (fungal strains), Pseudomonas vancouverensis, and Flavobacterium sp. (bacterial strains). The surfaces of sandstone and whitewood samples were inoculated with these microorganisms before or after applying Or-NCs and Th-NCs. The concentration-dependent effect of Or-NCs and Th-NCs on biofilm viability was determined by the MTT reduction assay. The results showed that Or-NCs and Th-NCs possess effective disinfection and anti-biofilm activity. Diffuse reflectivity measurements revealed no visible color changes of the materials after the application of the nanoencapsulated essential oils.

Study of the Chemical Profile and Anti-Fungal Activity against Candida auris of Cinnamomum cassia Essential Oil and of Its Nano-Formulations Based on Polycaprolactone

BACKGROUND

Candida auris represents an emerging pathogen that results in nosocomial infections and is considered a serious global health problem. The aim of this work was to evaluate the in vitro antifungal efficacy of Cinnamomum cassia essential oil (CC-EO) pure or formulated in polycaprolactone (PCL) nanoparticles against ten clinical strains of C. auris.

METHODS

nanoparticles of PCL were produced using CC-EO (nano-CC-EO) and cinnamaldehyde (CIN) through the nanoprecipitation method. The chemical profile of both CC-EO and nano-CC-EO was evaluated using SPME sampling followed by GC-MS analysis. Micro-broth dilution tests were performed to evaluate both fungistatic and fungicidal effectiveness of CC-EO and CIN, pure and nano-formulated. Furthermore, checkerboard tests to evaluate the synergistic action of CC-EO or nano-CC-EO with micafungin or fluconazole were conducted. Finally, the biofilm disrupting activity of both formulations was evaluated.

RESULTS

GC-MS analysis shows a different composition between CC-EO and nano-CC-EO. Moreover, the microbiological analyses do not show any variation in antifungal effectiveness either towards the planktonic form (MIC_CC-EO = 0.01 ± 0.01 and MIC_nano-CC-EO = 0.02 ± 0.01) or the biofilm form. No synergistic activity with the antifungal drugs tested was found.

CONCLUSIONS

both CC-EO and nano-CC-EO show the same antimicrobial effectiveness and are potential assets in the fight against C. auris.

European survey on the current surveillance practices, management guidelines, treatment pathways and heterogeneity of testing of Clostridioides difficile, 2018-2019: results from The Combatting Bacterial Resistance in Europe CDI (COMBACTE-CDI)

BACKGROUND

Awareness and compliance with international guidelines for diagnosis and clinical management of Clostridioides difficile infection (CDI) are unknown.

AIM

To compare the awareness and compliance with the recommended strategies for diagnosis and clinical management of CDI across Europe in 2018-2019.

METHODS

Hospital sites and their associated community practices across 12 European countries completed an online survey in 2018-2019, to report on their practices in terms of surveillance, prevention, diagnosis, and treatment of CDI. Responses were collected from 105 hospitals and 39 community general practitioners (GPs).

FINDINGS

Hospital sites of 11 countries reported participation in national surveillance schemes compared with six countries for international schemes. The European Society of Clinical Microbiology and Infectious Diseases (ESCMID)-recommended CDI testing methodologies were used by 82% (86/105) of hospitals, however countries reporting the highest incidence of CDI used non-recommended tests. Over 75% (80/105) of hospitals were aware of the most recent European CDI treatment guidelines at the time of this survey compared with only 26% (10/39) of surveyed GPs. However, up to 15% (16/105) of hospitals reported using the non-recommended metronidazole for recurrent CDI cases, sites in countries with lower awareness of CDI treatment guidelines. Only 37% (39/105) of hospitals adopted contact isolation precautions in case of suspected CDI.

CONCLUSION

Good awareness of guidelines for the management of CDI was observed across the surveyed European hospital sites. However, low compliance with diagnostic testing guidelines, infection control measures for suspected CDI, and insufficient awareness of treatment guidelines continued to be reported in some countries.

Effect of Petal Color, Water Status, and Extraction Method on Qualitative Characteristics of Rosa rugosa Liqueur

Flowers of Rosa rugosa Thunb. are a rich source of bioactive compounds with high antioxidant properties and are used for the production of jams, teas, juices, and wines. In the present paper, the petals of R. rugosa cv. Alba (white flowers) and Rubra (purple flowers) were evaluated for their morphological and phytochemical characteristics, and for the preparation of an alcoholic liqueur. In particular, the effect of two extraction procedures (conventional and maceration) of fresh and dry petals on the quality of a rose liqueur was determined. As expected, the concentration of the flower's bioactive compounds was affected by petal water content and by tested cultivars: dry petals showed higher total carotenoids and anthocyanins contents with respect to the fresh ones; cv. Rubra evidenced higher values compared to cv. Alba. As regards the quality of rose liqueur, the two petal extraction procedures did not affect the polyphenol content and higher values were recorded only on dry petals with respect to the fresh ones and, in particular, on those from cv. Rubra. The liqueur's flavonoid content was influenced by the petal extraction method, water content, and color as higher values were recorded on rose liqueur prepared after the maceration of cv. Rubra dry petals whereas lower values were observed on alcoholic drinks prepared after the conventional extraction of cv. Alba fresh petals. Our study shows that R. rugosa petals have a fair amount of secondary metabolites with antioxidant activity, making them suitable for use in the beverage industry.

Polymeric Nanocapsules Containing Fennel Essential Oil: Their Preparation, Physicochemical Characterization, Stability over Time and in Simulated Gastrointestinal Conditions

Plant essential oils, a source of biologically active compounds, represent a promising segment in the pharmaceutical market. However, their volatility, hydrophobicity, poor stability, and low toxicity limit direct use in pharmaceutical-related applications. Nanoencapsulation is a technique that allows overcoming these obstacles by improving bioaccessibility and bioavailability. Nanocapsules (NCs) based on biodegradable and biocompatible poly(ɛ-caprolactone) containing Foeniculum vulgare Mill. essential oil (FEO), known for its biological activities, were successfully prepared by interfacial deposition of the preformed polymer method. The composition of FEO (trans-anethole chemotype) was determined by gas chromatography analyses. The FEO presence inside the NCs was confirmed by nuclear magnetic resonance experiments. The FEO-NCs showed nanometer size (210 nm), low polydispersity index (0.10), negative zeta potential (−15 mV), non-Newtonian rheological behavior, and high efficiency of encapsulation (93%). Moreover, parameters such as FEO-NC particle size, bioactive compound retention, and FEO composition were monitored for 30 days at storage temperatures of 4 and 40 °C, confirming the robustness of the nanosystem. Finally, FEO-NCs were resistant to the simulated gastric digestion and showed an effective bioaccessibility of 29% in simulated intestinal digestion. Based on the results obtained, this FEO-NC nanosystem could find interesting applications in the nutraceutical and pharmaceutical sectors.

Development and Validation of an AI-driven Mammographic Breast Density Classification Tool Based on Radiologist Consensus

Mammographic breast density (BD) is commonly visually assessed using the Breast Imaging Reporting and Data System (BI-RADS) four-category scale. To overcome inter- and intraobserver variability of visual assessment, the authors retrospectively developed and externally validated a software for BD classification based on convolutional neural networks from mammograms obtained between 2017 and 2020. The tool was trained using the majority BD category determined by seven board-certified radiologists who independently visually assessed 760 mediolateral oblique (MLO) images in 380 women (mean age, 57 years ± 6 [SD]) from center 1; this process mimicked training from a consensus of several human readers. External validation of the model was performed by the three radiologists whose BD assessment was closest to the majority (consensus) of the initial seven on a dataset of 384 MLO images in 197 women (mean age, 56 years ± 13) obtained from center 2. The model achieved an accuracy of 89.3% in distinguishing BI-RADS a or b (nondense breasts) versus c or d (dense breasts) categories, with an agreement of 90.4% (178 of 197 mammograms) and a reliability of 0.807 (Cohen κ) compared with the mode of the three readers. This study demonstrates accuracy and reliability of a fully automated software for BD classification. Keywords: Mammography, Breast, Convolutional Neural Network (CNN), Deep Learning Algorithms, Machine Learning Algorithms Supplemental material is available for this article. © RSNA, 2022.

A Psychometric Platform to Collect Somatosensory Sensations for Neuroprosthetic Use

Somatosensory neuroprostheses exploit invasive and non-invasive feedback technologies to restore sensorimotor functions lost to disease or trauma. These devices use electrical stimulation to communicate sensory information to the brain. A sensation characterization procedure is thus necessary to determine the appropriate stimulation parameters and to establish a clear personalized map of the sensations that can be restored. Several questionnaires have been described in the literature to collect the quality, type, location, and intensity of the evoked sensations, but there is still no standard psychometric platform. Here, we propose a new psychometric system containing previously validated questionnaires on evoked sensations, which can be applied to any kind of somatosensory neuroprosthesis. The platform collects stimulation parameters used to elicit sensations and records subjects' percepts in terms of sensation location, type, quality, perceptual threshold, and intensity. It further collects data using standardized assessment questionnaires and scales, performs measurements over time, and collects phantom limb pain syndrome data. The psychometric platform is user-friendly and provides clinicians with all the information needed to assess the sensory feedback. The psychometric platform was validated with three trans-radial amputees. The platform was used to assess intraneural sensory feedback provided through implanted peripheral nerve interfaces. The proposed platform could act as a new standardized assessment toolbox to homogenize the reporting of results obtained with different technologies in the field of somatosensory neuroprosthetics.

Modified Sling Technique for Difficult Filter Retrieval

Caval filters are placed in the inferior vena cava (IVC) to prevent pulmonary thromboembolism in patients with deep vein thrombosis. If there is no indication for thrombo-embolic risk prevention, the filter can be removed to reduce potential filter-related complications. Advanced endovascular techniques are frequently used to retrieve IVC filters. We describe an alternative filter-removal technique for use when standard techniques are not practicable. In our method, the filter hook is embedded within the IVC wall. To retrieve it, a long introducer is inserted; a guidewire and the "loop snare" retrieval system are then advanced through it with a coaxial system and positioned below the filter at the level of the common iliac vein confluence. The guidewire is then passed through the loop, creating a "sling" around the filter which allows the application of traction from the bottom upwards, releasing the hook from the wall. The loop is then held under tension with the filter aligned in the IVC lumen, and the introducer is advanced distally to completely cover the filter, allowing complete retrieval of the filter without damaging the vessel walls. This modified Sling technique is a safe and feasible method for complicated IVC filter retrieval.

Multinodular plexiform tumors of major peripheral nerves: A practical overview

BACKGROUND AND AIMS

Multinodular/plexiform schwannomas and neurofibromas of major nerves are rare: before surgery, differential diagnosis among these two uncommon variants is challenging. For both forms, surgical removal is recommended in case of progressive growth and worsening of neurological symptoms. Surgery has a higher risk of neurological damage than conventional schwannomas or neurofibromas. In literature, a comparison among these rare tumors is usually limited to the pathological aspect while specific surgical and clinical management indications are lacking. Cutaneous tumors of both forms arising from terminal peripheral nerves' branches might be treated by plastic surgeons while tumors of major nerves remain under neurosurgical competence. Here we report our recent neurosurgical experience on the matter, to furnish useful suggestions for the management of these tumors.

METHOD

We analyzed the clinical, radiological, and pathological data in a consecutive case series of plexiform/multinodular nerve tumors operated at our institution in the last five years.

RESULTS

In our series, neurofibroma type of plexiform tumors was more frequent than schwannoma type: two sporadic plexiform-multinodular schwannomas (patients 1, and 5) and three multinodular/plexiform Neurofibromatosis familial (Neurofibromatosis 1 / NF-1) (patients 2, 3, and 4). Surgery was complex when major nerves were involved. The early outcome appeared mostly related to the pre-surgical neurological conditions and histological grading.

INTERPRETATION

Although sharing some features, multinodular-plexiform schwannomas and neurofibromas have consistent differences from the clinical, surgical and pathological points of view.

Non-invasive electrical brain stimulation for vision restoration after stroke: An exploratory randomized trial (REVIS)

Background:

Occipital strokes often cause permanent homonymous hemianopia leading to significant disability. In previous studies, non-invasive electrical brain stimulation (NIBS) has improved vision after optic nerve damage and in combination with training after stroke.

Objective:

We explored different NIBS modalities for rehabilitation of hemianopia after chronic stroke.

Methods:

In a randomized, double-blinded, sham-controlled, three-armed trial, altogether 56 patients with homonymous hemianopia were recruited. The three experiments were: i) repetitive transorbital alternating current stimulation (rtACS, n = 8) vs. rtACS with prior cathodal transcranial direct current stimulation over the intact visual cortex (tDCS/rtACS, n = 8) vs. sham (n = 8); ii) rtACS (n = 9) vs. sham (n = 9); and iii) tDCS of the visual cortex (n = 7) vs. sham (n = 7). Visual functions were evaluated before and after the intervention, and after eight weeks follow-up. The primary outcome was change in visual field assessed by high-resolution and standard perimetries. The individual modalities were compared within each experimental arm.

Results:

Primary outcomes in Experiments 1 and 2 were negative. Only significant between-group change was observed in Experiment 3, where tDCS increased visual field of the contralesional eye compared to sham. tDCS/rtACS improved dynamic vision, reading, and visual field of the contralesional eye, but was not superior to other groups. rtACS alone increased foveal sensitivity, but was otherwise ineffective. All trial-related procedures were tolerated well.

Conclusions:

This exploratory trial showed safety but no main effect of NIBS on vision restoration after stroke. However, tDCS and combined tDCS/rtACS induced improvements in visually guided performance that need to be confirmed in larger-sample trials.

NCT01418820 (clinicaltrials.gov)

Oregano and Thyme Essential Oils Encapsulated in Chitosan Nanoparticles as Effective Antimicrobial Agents against Foodborne Pathogens

The use of natural compounds with biocidal activity to fight the growth of bacteria responsible for foodborne illness is one of the main research challenges in the food sector. This study reports the preparation and physicochemical characterization of chitosan nanoparticles loaded with Thymus capitatus (Th-CNPs) and Origanum vulgare (Or-CNPs) essential oils. The nanosystems were obtained by ionotropic gelation technique with high encapsulation efficiency (80-83%) and loading capacity (26-27%). Nanoparticles showed a spherical shape, bimodal particle size distribution, and good stability (zeta potential values > 40 mV). The treatment of the nanosuspensions at different temperatures (4 and 40 °C) and storage times (7, 15, 21, and 30 days) did not affect their physicochemical parameters and highlights their reservoir ability for essential oils also under stressful conditions. Both Or-CNPs and Th-CNPs exhibited an enhanced bactericidal activity against foodborne pathogens (S. aureus, E. coli, L. monocytogenes) than pure essential oils. These ecofriendly nanosystems could represent a valid alternative to synthetic preservatives and be of interest for health and food safety.

Biofilm inhibition by biocompatible poly(ε-caprolactone) nanocapsules loaded with essential oils and their cyto/genotoxicity to human keratinocyte cell line

Essential oils (EOs) of Thymus capitatus (Th) carvacrol chemotype and Origanum vulgare (Or) thymol and carvacrol chemotype were encapsulated in biocompatible poly(ε-caprolactone) nanocapsules (NCs). These nanosystems exhibited antibacterial, antifungal, and antibiofilm activities against Staphylococcus aureus, Escherichia coli, and Candida albicans. Th-NCs and Or-NCs were more effective against all tested strains than pure EOs and at the same time were not cytotoxic on HaCaT (T0020001) human keratinocyte cell line. The genotoxic effects of EO-NCs and EOs on HaCaT were evaluated using an alkaline comet assay for the first time, revealing that Th-NCs and Or-NCs did not induce DNA damage compared with untreated control HaCaT cells in vitro after 24 h. The cells morphological changes were assessed by label-free live cell Raman imaging. This study demonstrate the ability of poly(ε-caprolactone) nanocapsules loaded with thyme and oregano EOs to reduce microbial and biofilm growth and could be an ecological alternative in the development of new antimicrobial strategies.

Resorbable Purified Porcine Skin Gelatin Cross-Linked with Glutaraldehyde Spheres for Preoperative Embolization of Carotid Body Paraganglioma

Chemodectomas are rare neuroendocrine tumors that typically arise at the carotid bifurcation and progressively englobe the internal and external carotid artery. Surgical asportation of the capsulated mass is the elective treatment. Pre-procedural embolization of this high vascular tumors is highly recommended because it has shown to improve surgical outcome by reducing both, mean blood loss and total operation time. Many different embolization techniques have been described in literature. In the here presented case we opted for an endovascular approach using resorbable purified porcine skin gelatin cross-linked with glutaraldehyde microspheres (Optisphere - MEDTRONIC) as an embolic agent. These turned out to be very safe and effective in improving surgical outcome by reducing operative blood loss and thus reducing treatment-related morbidity.

Computational approaches to decode grasping force and velocity level in upper-limb amputee from intraneural peripheral signals

Objective. Recent results have shown the potentials of neural interfaces to provide sensory feedback to subjects with limb amputation increasing prosthesis usability. However, their advantages for decoding motor control signals over current methods based on electromyography (EMG) are still debated. In this study we compared a standard EMG-based method with approaches that use peripheral intraneural data to infer distinct levels of grasping force and velocity in a trans-radial amputee.Approach. Surface EMG (three channels) and intraneural signals (collected with transverse intrafascicular multichannel electrodes, TIMEs, 56 channels) were simultaneously recorded during the amputee's intended grasping movements. We sorted single unit activity (SUA) from each neural signal and then we identified the most informative units. EMG envelopes were extracted from the recorded EMG signals. A reference support vector machine (SVM) classifier was used to map EMG envelopes into desired force and velocity levels. Two decoding approaches using SUA were then tested and compared to the EMG-based reference classifier: (a) SVM classification of firing rates into desired force and velocity levels; (b) reconstruction of covariates (the grasp cue level or EMG envelopes) from neural data and use of covariates for classification into desired force and velocity levels.Main results.Using EMG envelopes as reconstructed covariates from SUA yielded significantly better results than the other approaches tested, with performance similar to that of the EMG-based reference classifier, and stable over three different recording days. Of the two reconstruction algorithms used in this approach, a linear Kalman filter and a nonlinear point process adaptive filter, the nonlinear filter gave better results.Significance.This study presented a new effective approach for decoding grasping force and velocity from peripheral intraneural signals in a trans-radial amputee, which relies on using SUA to reconstruct EMG envelopes. Being dependent on EMG recordings only for the training phase, this approach can fully exploit the advantages of implanted neural interfaces and potentially overcome, in the medium to long term, current state-of-the-art methods. (Clinical trial's registration number: NCT02848846).

Postpartum Hemorrhages: Prevention

The strict correlation between abnormal invasive placentation and postpartum hemorrhage suggests that a widespread antenatal diagnosis of placental anomalies would improve the management of these challenging patients; acting preventive solutions at the moment of delivery reduces blood loss and avoid hysterectomies. The role of endovascular procedures in this field has been encouraged by multiple studies reporting prophylactic uterine arteries embolization and iliac/aortic balloon catheters positioning. This paper aims to review the main imaging diagnostic findings of placental implant anomalies and summarize the principal preventive endovascular strategies proposed in literature.

Binding Affinity and Driving Forces for the Interaction of Calixarene-Based Micellar Aggregates With Model Antibiotics in Neutral Aqueous Solution

The search for novel surfactants or drug delivery systems able to improve the performance of old-generation antibiotics is a topic of great interest. Self-assembling amphiphilic calix[4]arene derivatives provide well-defined nanostructured systems that exhibit promising features for antibiotics delivery. In this work, we investigated the capability of two micellar polycationic calix[4]arene derivatives to recognize and host ofloxacin, chloramphenicol, or tetracycline in neutral aqueous solution. The formation of the nanoaggregates and the host–guest equilibria were examined by nano-isothermal titration calorimetry, dynamic light scattering, and mono- and bi-dimensional NMR. The thermodynamic characterization revealed that the calix[4]arene-based micellar aggregates are able to effectively entrap the model antibiotics and enabled the determination of both the species and the driving forces for the molecular recognition process. Indeed, the formation of the chloramphenicol–micelle adduct was found to be enthalpy driven, whereas entropy drives the formation of the adducts with both ofloxacin and tetracycline. NMR spectra corroborated ITC data about the positioning of the antibiotics in the calixarene nanoaggregates.

A closed-loop hand prosthesis with simultaneous intraneural tactile and position feedback

Current myoelectric prostheses allow transradial amputees to regain voluntary motor control of their artificial limb by exploiting residual muscle function in the forearm. However, the overreliance on visual cues resulting from a lack of sensory feedback is a common complaint. Recently, several groups have provided tactile feedback in upper limb amputees using implanted electrodes, surface nerve stimulation, or sensory substitution. These approaches have led to improved function and prosthesis embodiment. Nevertheless, the provided information remains limited to a subset of the rich sensory cues available to healthy individuals. More specifically, proprioception, the sense of limb position and movement, is predominantly absent from current systems. Here, we show that sensory substitution based on intraneural stimulation can deliver position feedback in real time and in conjunction with somatotopic tactile feedback. This approach allowed two transradial amputees to regain high and close-to-natural remapped proprioceptive acuity, with a median joint angle reproduction precision of 9.1° and a median threshold to detection of passive movements of 9.5°, which was comparable with results obtained in healthy participants. The simultaneous delivery of position information and somatotopic tactile feedback allowed both amputees to discriminate the size and compliance of four objects with high levels of performance (75.5%). These results demonstrate that tactile information delivered via somatotopic neural stimulation and position information delivered via sensory substitution can be exploited simultaneously and efficiently by transradial amputees. This study paves a way to more sophisticated bidirectional bionic limbs conveying richer, multimodal sensations.

Nanoencapsulated Essential Oils with Enhanced Antifungal Activity for Potential Application on Agri-Food, Material and Environmental Fields

Nanotechnology is a new frontier of this century that finds applications in various fields of science with important effects on our life and on the environment. Nanoencapsulation of bioactive compounds is a promising topic of nanotechnology. The excessive use of synthetic compounds with antifungal activity has led to the selection of resistant fungal species. In this context, the use of plant essential oils (EOs) with antifungal activity encapsulated in ecofriendly nanosystems could be a new and winning strategy to overcome the problem. We prepared nanoencapsules containing the essential oils of Origanum vulgare (OV) and Thymus capitatus (TC) by the nanoprecipitation method. The colloidal suspensions were characterized for size, polydispersity index (PDI), zeta potential, efficiency of encapsulation (EE) and loading capacity (LC). Finally, the essential oil nanosuspensions were assayed against a panel of fourteen fungal strains belonging to the Ascomycota and Basidiomycota phyla. Our results show that the nanosystems containing thyme and oregano essential oils were active against various fungal strains from natural environments and materials. In particular, the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values were two to four times lower than the pure essential oils. The aqueous, ecofriendly essential oil nanosuspensions with broad-spectrum antifungal activity could be a valid alternative to synthetic products, finding interesting applications in the agri-food and environmental fields.

Electroencephalography-Derived Prognosis of Functional Recovery in Acute Stroke Through Machine Learning Approaches

Stroke, if not lethal, is a primary cause of disability. Early assessment of markers of recovery can allow personalized interventions; however, it is difficult to deliver indexes in the acute phase able to predict recovery. In this perspective, evaluation of electrical brain activity may provide useful information. A machine learning approach was explored here to predict post-stroke recovery relying on multi-channel electroencephalographic (EEG) recordings of few minutes performed at rest. A data-driven model, based on partial least square (PLS) regression, was trained on 19-channel EEG recordings performed within 10 days after mono-hemispheric stroke in 101 patients. The band-wise (delta: 1-4[Formula: see text]Hz, theta: 4-7[Formula: see text]Hz, alpha: 8-14[Formula: see text]Hz and beta: 15-30[Formula: see text]Hz) EEG effective powers were used as features to predict the recovery at 6 months (based on clinical status evaluated through the NIH Stroke Scale, NIHSS) in an optimized and cross-validated framework. In order to exploit the multimodal contribution to prognosis, the EEG-based prediction of recovery was combined with NIHSS scores in the acute phase and both were fed to a nonlinear support vector regressor (SVR). The prediction performance of EEG was at least as good as that of the acute clinical status scores. A posteriori evaluation of the features exploited by the analysis highlighted a lower delta and higher alpha activity in patients showing a positive outcome, independently of the affected hemisphere. The multimodal approach showed better prediction capabilities compared to the acute NIHSS scores alone ([Formula: see text] versus [Formula: see text], AUC = 0.80 versus AUC = 0.70, [Formula: see text]). The multimodal and multivariate model can be used in acute phase to infer recovery relying on standard EEG recordings of few minutes performed at rest together with clinical assessment, to be exploited for early and personalized therapies. The easiness of performing EEG may allow such an approach to become a standard-of-care and, thanks to the increasing number of labeled samples, further improving the model predictive power.

Brain reactions to the use of sensorized hand prosthesis in amputees

OBJECTIVE

We investigated for the first time the presence of chronic changes in the functional organization of sensorimotor brain areas induced by prolonged training with a bidirectional hand prosthesis.

METHODS

A multimodal neurophysiological and neuroimaging evaluation of brain functional changes occurring during training in five consecutive amputees participating to experimental trials with robotic hands over a period of 10 years was carried out. In particular, modifications to the functional anatomy of sensorimotor brain areas under resting conditions were explored in order to check for eventual changes with respect to baseline.

RESULTS

Full evidence is provided to demonstrate brain functional changes, and some of them in both the hemispheres and others restricted to the hemisphere contralateral to the amputation/prosthetic hand.

CONCLUSIONS

The study describes a unique experimental experience showing that brain reactions to the prolonged use of an artificial hand can be tracked for a tailored approach to a fully embedded artificial upper limb for future chronic uses in daily activities.

Quantum Chemical and Molecular Dynamics Studies of MUC1 Calix[4,8]arene Scaffold Based Anticancer Vaccine Candidates

Functional antitumor vaccine constructs are the basis for active tumor immunotherapy, which is useful in the treatment of many types of cancers. MUC1 is one key glycoprotein for targeting and designing new strategies for multicomponent vaccines. Two self-adjuvant tetravalent vaccine candidates were prepared by clustering four or eight PDTRP MUC1 core epitope sequences on calixarene scaffolds. In this work, the different activities of two molecules with calix[4]arene and calix[8]arene skeleton are rationalized. Quantum mechanics, docking, and molecular dynamics structural optimization were first carried out followed by metadynamics to calculate the energy profiles. Further insights were obtained by complementarity studies of molecular fields. The molecular modeling results are in strong agreement with the experimental in vivo immunogenicity data. In conclusion, the overall data shows that, in the designing of anticancer vaccines, scaffold flexibility has a pivotal role in obtaining a suitable electrostatic, hydrophobic, and steric complementarity with the biological target.

Small Fibre Involvement in Multifocal Motor Neuropathy Explored with Sudoscan: A Single-Centre Experience

Objective: Multifocal motor neuropathy (MMN) is a rare inflammatory neuropathy, clinically characterized by exclusive motor involvement. We wished to evaluate the possible presence of sensory dysfunction, including the evaluation of small fibres, after a long-term disease course. Patients and methods: seven MMN patients, regularly followed in our Neurology Department, underwent clinical evaluation, neurophysiological examination by nerve conduction studies (NCSs), and Sudoscan. We compared neurophysiological data with a group of patients with other disorders of the peripheral nervous system. Results: NCSs showed a reduction of sensory nerve action potential amplitude in 2/7 MMN patients. Sudoscan showed borderline electrochemical skin conductance (ESC) values in 3/7 MMN patients (two of them with abnormal sensory NCSs). Conclusions: Our results confirm that sensory involvement may be found in some MMN after a long-term disease course, and it could also involve the small fibres.

Software-assisted US/MRI fusion-targeted biopsy for prostate cancer

BACKGROUND

Prostate cancer is the first cancer diagnosis in men. European Association of Urology  (EAU) Guidelines for Prostate Cancer underline the importance of screening, performed through PSA testing on all men with more than 50 years of age and before on men with risk factors. The diagnosis is still histopathologic, and it is done on the basis of the findings on biopsy samples.

MATERIALS AND METHODS

Fusion biopsy is a relatively new technique that allows the operator to perform the biopsies in office instead of the MRI gantry, without losing the detection capability of MRI. The  T2-wighted images obtained during a previous mpMRI are merged with the real-time ones of the TRUS.

RESULTS

Fusion biopsy in comparison with the systematic standard biopsy has a better detection rate of clinically significant cancers and of any cancers.

CONCLUSION

EAU 2020 guidelines still do offer a list of indications of when the biopsy should be performed, but it still appeared to be overperformed. The aim of our study is to underline how, in accordance with the recent literature result,  fusion biopsy has showed a better detection rate of any cancer and clinically significant disease with a reduced numbers of samplings, and no substantial difference between the multiple software.

Cooled radiofrequency ablation technology for painful bone tumors

Bone metastases are a common cause of cancer-related debilitating pain, especially when -localized in the vertebral column and not responsive to standard treatment. In such cases, various treatment options are available; among these is Radiofrequency, whose role has been rapidly growing over the past few years. In this study, we used the innovative Osteocool RF Ablation System (Medtronic) on a patient with a painful bone metastasis localized in the 5th lumbar vertebra, with encouraging results. The radiofrequency ablation of bone metastases with palliative aim represents an excellent treatment option, as it is a minimally invasive and safe procedure, and can be repeated multiple times.

Use of perfusional CBCT imaging for intraprocedural evaluation of endovascular treatment in patients with diabetic foot: a concept paper

Diabetes mellitus (DM) is one of the most common metabolic diseases worldwide; its global burden has increased rapidly over the past decade, enough to be considered a public health emergency in many countries. Diabetic foot disease and, particularly diabetic foot ulceration, is the major complication of DM: through a skin damage of the foot, with a loss of epithelial tissue, it can deepen to muscles and bones and lead to the amputation of the lower limbs. Peripheral arterial disease (PAD) in patients with diabetes, manifests like a diffuse macroangiopathic multi-segmental involvement of the lower limb vessels, also connected to a damage of collateral circulation; it may also display characteristic microaneurysms and tortuosity in distal arteries. As validation method, Bold-MRI is used. The diabetic foot should be handled with a multidisciplinary team approach, as its management requires systemic and localized treatments, pain control, monitoring of cardiovascular risk factors and other comorbidities. CBCT is an emerging medical imaging technique with the original feature of divergent radiation, forming a cone, in contrast with the spiral slicing of conventional CT, and has become increasingly important in treatment planning and diagnosis: from small anatomical areas, such as implantology, to the world of interventional radiology, with a wide range of applications: as guidance for biopsies or ablation treatments. The aim of this project is to evaluate the usefulness of perfusion CBCT imaging, obtained during endovascular revascularization, for intraprocedural evaluation of endovascular treatment in patients with diabetic foot. (www.actabiomedica.it).

Cortical plasticity after hand prostheses use: Is the hypothesis of deafferented cortex "invasion" always true?

OBJECTIVE

To study motor cortex plasticity after a period of training with a new prototype of bidirectional hand prosthesis in three left trans-radial amputees, correlating these changes with the modification of Phantom Limb Pain (PLP) in the same period.

METHODS

Each subject underwent a brain motor mapping with Transcranial Magnetic Stimulation (TMS) and PLP evaluation with questionnaires during a six-month training with a prototype of bidirectional hand prosthesis.

RESULTS

The baseline motor maps showed in all three amputees a smaller area of muscles representation of the amputated side compared to the intact limb. After training, there was a partial reversal of the baseline asymmetry. The two subjects affected by PLP experienced a statistically significant reduction of pain.

CONCLUSIONS

Two apparently opposite findings, the invasion of the "deafferented" cortex by neighbouring areas and the "persistence" of neural structures after amputation, could vary according to different target used for measurement. Our results do not support a correlation between PLP and motor cortical changes.

SIGNIFICANCE

The selection of the target and of the task is essential for studies investigating motor brain plasticity. This study boosts against a direct and unique role of motor cortical changes on PLP genesis.

Sensitivity to temporal parameters of intraneural tactile sensory feedback

BACKGROUND

Recent studies have shown that neural stimulation can be used to provide artificial sensory feedback to amputees eliciting sensations referred on the amputated hand. The temporal properties of the neural stimulation modulate aspects of evoked sensations that can be exploited in a bidirectional hand prosthesis.

METHODS

We previously collected evidence that the derivative of the amplitude of the stimulation (intra-digit temporal dynamics) allows subjects to recognize object compliance and that the time delay among stimuli injected through electrodes implanted in different nerves (inter-digit temporal distance) allows to recognize object shapes. Nevertheless, a detailed characterization of the subjects' sensitivity to variations of intra-digit temporal dynamic and inter-digit temporal distance of the intraneural tactile feedback has not been executed. An exhaustive understanding of the overall potentials and limits of intraneural stimulation to deliver sensory feedback is of paramount importance to bring this approach closer and closer to the natural situation. To this aim, here we asked two trans-radial amputees to identify stimuli with different temporal characteristics delivered to the same active site (intra-digit temporal Dynamic Recognition (DR)) or between two active sites (inter-digit Temporal distance Recognition (TR)). Finally, we compared the results achieved for (simulated) TR with conceptually similar experiments with real objects with one subject.

RESULTS

We found that the subjects were able to identify stimuli with temporal differences (perceptual thresholds) larger than 0.25 s for DR and larger than 0.125 s for TR, respectively. Moreover, we also found no statistically significant differences when the subjects were asked to identify three objects during simulated 'open-loop' TR experiments or real 'closed-loop' tests while controlling robotic hand.

CONCLUSIONS

This study is a new step towards a more detailed analysis of the overall potentials and limits of intraneural sensory feedback. A full characterization is necessary to develop more advanced prostheses capable of restoring all lost functions and of being perceived more as a natural limb by users.

Oregano (Origanum vulgare L.) essential oil provides anti-inflammatory activity and facilitates wound healing in a human keratinocytes cell model

Skin acts as a protective barrier between the body and the external environment. Skin wounds are a common inflammatory disorder for the solution of which plants and essential oils have been applied as a medical option for centuries. Origanum vulgare essential oil (OEO) is largely used in folk medicine, but its molecular mechanisms of action are not fully known. In this study, we evaluated the anti-inflammatory/antioxidant activity as well as wound healing capacity of a well-characterized OEO on human keratinocytes NCTC 2544 treated with interferon-gamma (IFN-γ) and histamine (H) or subjected to a scratch test. The expression of pro-inflammatory mediators such as reactive oxygen species (ROS), inter-cellular adhesion molecule (ICAM)-1, inducible nitric oxide synthase (iNOS), and cyclooxygenase (COX)-2 were verified. The DNA damage was shown by the formation of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-OHdG) and activation of proliferating cell nuclear antigen (PCNA). Moreover, the abnormal modification of extracellular matrix components (ECM) was examined by determining matrix metalloproteinase (MMP)-1, and -12. Compared to untreated control, OEO showed efficacy in supporting and enhancing the cell motility. In IFN-γ and H treated cells, OEO displayed a significant reduction of ROS, ICAM-1, iNOS, COX-2, 8-OHdG, MMP-1, and MMP-12. OEO proved useful to treat inflammation and support cell motility during wound healing.

Preparation of a radiology department in an Italian hospital dedicated to COVID-19 patients

Preparedness for the ongoing coronavirus disease 2019 (COVID-19) and its spread in Italy called for setting up of adequately equipped and dedicated health facilities to manage sick patients while protecting healthcare workers, uninfected patients, and the community. In our country, in a short time span, the demand for critical care beds exceeded supply. A new sequestered hospital completely dedicated to intensive care (IC) for isolated COVID-19 patients needed to be designed, constructed, and deployed. Along with this new initiative, the new concept of "Pandemic Radiology Unit" was implemented as a practical solution to the emerging crisis, born out of a critical and urgent acute need. The present article describes logistics, planning, and practical design issues for such a pandemic radiology and critical care unit (e.g., space, infection control, safety of healthcare workers, etc.) adopted in the IC Hospital Unit for the care and management of COVID-19 patients.

Stability of flexible thin-film metallization stimulation electrodes: analysis of explants after first-in-human study and improvement of in vivo performance

OBJECTIVE

Micro-fabricated neural interfaces based on polyimide (PI) are achieving increasing importance in translational research. The ability to produce well-defined micro-structures with properties that include chemical inertness, mechanical flexibility and low water uptake are key advantages for these devices.

APPROACH

This paper reports the development of the transverse intrafascicular multichannel electrode (TIME) used to deliver intraneural sensory feedback to an upper-limb amputee in combination with a sensorized hand prosthesis. A failure mode analysis on the explanted devices was performed after a first-in-human study limited to 30 d.

MAIN RESULTS

About 90% of the stimulation contact sites of the TIMEs maintained electrical functionality and stability during the full implant period. However, optical analysis post-explantation revealed that 62.5% of the stimulation contacts showed signs of delamination at the metallization-PI interface. Such damage likely occurred due to handling during explantation and subsequent analysis, since a significant change in impedance was not observed in vivo. Nevertheless, whereas device integrity is mandatory for long-term functionality in chronic implantation, measures to increase the bonding strength of the metallization-PI interface deserve further investigation. We report here that silicon carbide (SiC) is an effective adhesion-promoting layer resisting heavy electrical stimulation conditions within a rodent animal trial. Optical analysis of the new electrodes revealed that the metallization remained unaltered after delivering over 14 million pulses in vivo without signs of delamination at the metallization-PI interface.

SIGNIFICANCE

Failure mode analysis guided implant stability optimization. Reliable adhesion of thin-film metallization to substrate has been proven using SiC, improving the potential transfer of micro-fabricated neural electrodes for chronic clinical applications. (Document number of Ethical Committee: P/905/CE/2012; Date of approval: 2012-10-04).

Balancing evidence and frontline experience in the early phases of the COVID-19 pandemic: current position of the Italian Society of Anti-infective Therapy (SITA) and the Italian Society of Pulmonology (SIP)

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease 2019 (COVID-19), which has rapidly become epidemic in Italy and other European countries. The disease spectrum ranges from asymptomatic/mildly symptomatic presentations to acute respiratory failure. At the present time the absolute number of severe cases requiring ventilator support is reaching or even surpassing the intensive care unit bed capacity in the most affected regions and countries.

OBJECTIVES

To narratively summarize the available literature on the management of COVID-19 in order to combine current evidence and frontline opinions and to provide balanced answers to pressing clinical questions.

SOURCES

Inductive PubMed search for publications relevant to the topic.

CONTENT

The available literature and the authors' frontline-based opinion are summarized in brief narrative answers to selected clinical questions, with a conclusive statement provided for each answer.

IMPLICATIONS

Many off-label antiviral and anti-inflammatory drugs are currently being administered to patients with COVID-19. Physicians must be aware that, as they are not supported by high-level evidence, these treatments may often be ethically justifiable only in those worsening patients unlikely to improve only with supportive care, and who cannot be enrolled onto randomized clinical trials. Access to well-designed randomized controlled trials should be expanded as much as possible because it is the most secure way to change for the better our approach to COVID-19 patients.

Decoding of grasping tasks from intraneural recordings in trans-radial amputee

OBJECTIVE

A major challenge in neuroprosthetics is the restoration of sensory-motor hand functions in upper-limb amputees. Neuroprostheses based on the direct re-connection of the peripheral nerves may be an interesting approach for re-establishing the natural and effective bidirectional control of hand prostheses. Recent results have shown that transverse intrafascicular multi-channel electrodes (TIMEs) can restore natural and sophisticated sensory feedback. However, the potential of using TIME-recorded motor intraneural signals to decode grasping tasks has not as yet been explored.

APPROACH

In this study, we show that several hand-movement intentions can be decoded from intraneural signals recorded using four TIMEs implanted in the median and ulnar nerves of an upper limb amputee. Experimental sessions were performed over a week, from day 16 to day 23 after the surgical operation. Intraneural activity was recorded during several hand motor tasks imagined by the subject and processed offline.

MAIN RESULTS

We obtained a very high decoding accuracy considering 11 class states (up to 83%). These results confirm that neural signals recorded by multi-channel intraneural electrodes can be used to decode several movement intentions with high accuracy. Moreover, we were able to use same TIME channels for decoding over one week within the first month, even if the stability has to be confirmed during long-term experiments.

SIGNIFICANCE

Therefore, TIMEs could be used in the future to achieve a complete bidirectional approach exploiting neural pathways, to make a more natural and intuitive new generation of hand prostheses that have a closer resemblance to a healthy hand.

Hand Control With Invasive Feedback Is Not Impaired by Increased Cognitive Load

Recent experiments have shown that neural stimulation can successfully restore sensory feedback in upper-limb amputees improving their ability to control the prosthesis. However, the potential advantages of invasive sensory feedback with respect to non-invasive solutions have not been yet identified. Our hypothesis was that a difference would appear when the subject cannot focus all the attention to the use of the prosthesis, but some additional activities require his/her cognitive attention, which is a quite common situation in real-life conditions. To verify this hypothesis, we asked a trans-radial amputee, equipped with a bidirectional hand prosthesis, to perform motor tasks also in combination with a cognitive task. Sensory feedback was provided via intraneural (invasive) or electro-tactile (non-invasive) stimulation. We collected also data related to self-confidence. While both approaches were able to significantly improve the motor performance of the subject when no additional cognitive effort was asked, the manual accuracy was not affected by the cognitive task only when intraneural feedback was provided. The highest self-confidence was obtained when intraneural sensory feedback was provided. Our findings show that intraneural sensory feedback is more robust to dual tasks than non-invasive feedback. This is the first direct comparison between invasive and non-invasive approaches for restoring sensory feedback and it could suggest an advantage of using invasive solutions. Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT02848846.

Injectable supramolecular nanohydrogel from a micellar self-assembling calix[4]arene derivative and curcumin for a sustained drug release

In the search for soft and smart materials for nanomedicine, which is a present challenge, supramolecular nanohydrogels built on self-assembling low-molecular-weight building blocks attract interest for their structural, mechanical and functional properties. Herein, we describe a supramolecular nanohydrogel formed by a biofriendly micellar self-assembling choline-calix[4]arene derivative in the presence of curcumin, a natural and multitarget pharmacologically relevant drug. Morphology and mechanical properties of the nanohydrogel were investigated, and theoretical simulation performed to model the nanohydrogel structure. The self-healing and injectable nanohydrogel easily formed in PBS medium at physiologic pH, without using additives and organic solvents. The micellar nanohydrogel protected curcumin from rapid chemical and photochemical degradation, and slowly dissolved in curcumin-loaded micelles sustaining the drug release in a low rate. The nanohydrogel which combines the mechanical properties of a hydrogel and the benefits of a nanoscale micelle in drug delivery, appears a promising novel material for drug delivery.