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1.
Nanoscale ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38779821

RESUMO

Catalytic activity is affected by surface morphology, and specific surfaces display greater activity than others. A key challenge is to define synthetic strategies to enhance the expression of more active surfaces and to maintain their stability during the lifespan of the catalyst. In this work, we outline an ab initio approach, based on density functional theory, to predict surface composition and particle morphology as a function of environmental conditions, and we apply this to CeO2 nanoparticles in the presence of co-adsorbed H2O and CO2 as an industrially relevant test case. We find that dissociative adsorption of both molecules is generally the most favourable, and that the presence of H2O can stabilise co-adsorbed CO2. We show that changes in adsorption strength with temperature and adsorbate partial pressure lead to significant changes in surface stability, and in particular that co-adsorption of H2O and CO2 stabilizes the {100} and {110} surfaces over the {111} surface. Based on the changes in surface free energy induced by the adsorbed species, we predict that cuboidal nanoparticles are favoured in the presence of co-adsorbed H2O and CO2, suggesting that cuboidal particles should experience a lower thermodynamic driving force to reconstruct and thus be more stable as catalysts for processes involving these species.

2.
J Long Term Eff Med Implants ; 34(3): 23-26, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505890

RESUMO

Schatzker III tibial plateau fractures (TPF) reduction and stabilization still represents a challenging procedure. We present an alternative, percutaneous surgical technique. With an antero-medial transverse incision at the level of the tibial metaphysis, under fluoroscopic control, an osteotome is advanced from medial to lateral, under the depressed fragments, reducing the articular surface of the lateral TP anatomically, without creating a significant void and preserving the lateral wall. Final fixation is achieved with screws placed from lateral to medial in a percutaneous fashion, parallel to the articular surface to hold fragments in a rafting way. Open surgical techniques hide many pitfalls and several new reduction options have been described; some simple but invasive, using bone tamps and bone graft that increase surgical trauma; others reliable and safe, but demanding and difficult to reproduce, needing good arthroscopic skills or special and expensive instrumentation, therefore not always available in the operating theater. We prefer a medially based percutaneous metaphyseal bone access using two simple flat low profile instruments such as osteotomes, that preserve bone and vascularization during the reduction maneuvers, minimizing the above-mentioned risks, for the treatment of Schatzker type III TPF.


Assuntos
Fraturas da Tíbia , Fraturas do Planalto Tibial , Humanos , Fixação Interna de Fraturas , Fluoroscopia , Fraturas da Tíbia/cirurgia , Transplante Ósseo
3.
Biomaterials ; 307: 122527, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38518591

RESUMO

Community-associated and hospital-acquired infections caused by bacteria continue to yield major global challenges to human health. Bacterial contamination on abiotic surfaces is largely spread via high-touch surfaces and contemporary standard disinfection practices show limited efficacy, resulting in unsatisfactory therapeutic outcomes. New strategies that offer non-specific and broad protection are urgently needed. Herein, we report our novel ceria-silver nanozyme engineered at a molar ratio of 5:1 and with a higher trivalent (Ce3+) surface fraction. Our results reveal potent levels of surface catalytic activity on both wet and dry surfaces, with rapid, and complete eradication of Pseudomonas aeruginosa, Staphylococcus aureus, and methicillin resistant S. aureus, in both planktonic and biofilm form. Preferential electrostatic adherence of anionic bacteria to the cationic nanozyme surface leads to a catastrophic loss in both aerobic and anaerobic respiration, DNA damage, osmodysregulation, and finally, programmed bacterial lysis. Our data reveal several unique mechanistic avenues of synergistic ceria-Ag efficacy. Ag potentially increases the presence of Ce3+ sites at the ceria-Ag interface, thereby facilitating the formation of harmful H2O2, followed by likely permeation across the cell wall. Further, a weakened Ag-induced Ce-O bond may drive electron transfer from the Ec band to O2, thereby further facilitating the selective reduction of O2 toward H2O2 formation. Ag destabilizes the surface adsorption of molecular H2O2, potentially leading to higher concentrations of free H2O2 adjacent to bacteria. To this end, our results show that H2O2 and/or NO/NO2-/NO3- are the key liberators of antibacterial activity, with a limited immediate role being offered by nanozyme-induced ROS including O2•- and OH•, and likely other light-activated radicals. A mini-pilot proof-of-concept study performed in a pediatric dental clinic setting confirms residual, and continual nanozyme antibacterial efficacy over a 28-day period. These findings open a new approach to alleviate infections caused by bacteria for use on high-touch hard surfaces.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Prata , Antibacterianos/farmacologia , Antibacterianos/química , Bactérias , Peróxido de Hidrogênio , Prata/farmacologia , Prata/química , Staphylococcus aureus
4.
Eur J Neurosci ; 59(5): 1029-1046, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38276915

RESUMO

Motor activation in response to perception of action-related stimuli may depend on a resonance mechanism subserving action understanding. The extent to which this mechanism is innate or learned from sensorimotor experience is still unclear. Here, we recorded EEG while people with paraplegia or tetraplegia consequent to spinal cord injury (SCI) and healthy control participants were presented with action sounds produced by body parts (mouth, hands or feet) that were or were not affected by SCI. Non-action sounds were used as further control. We observed reduced brain activation in subjects affected by SCI at both pre- and post-stimulus latencies specifically for those actions whose effector was disconnected by the spinal lesion (i.e., hand sound for tetraplegia and leg sound for both paraplegia and tetraplegia). Correlation analyses showed that these modulations were functionally linked with the chronicity of the lesion, indicating that the longer the time the lesion- EEG data acquisition interval and/or the more the lesion occurred at a young age, the weaker was the cortical activity in response to these action sounds. Tellingly, source estimations confirmed that these modulations originated from a deficit in the motor resonance mechanism, by showing diminished activity in premotor (during prediction and perception) and near the primary motor (during perception) areas. Such dissociation along the cortical hierarchy is consistent with both previous reports in healthy subjects and with hierarchical predictive coding accounts. Overall, these data expand on the notion that sensorimotor experience maintains the cortical representations relevant to anticipate and perceive action-related stimuli.


Assuntos
Traumatismos da Medula Espinal , Humanos , Traumatismos da Medula Espinal/patologia , Paraplegia , Som , Quadriplegia
5.
J Appl Stat ; 51(1): 114-138, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38179161

RESUMO

We propose a novel approach to the estimation of multiple Graphical Models to analyse temporal patterns of association among a set of metabolites over different groups of patients. Our motivating application is the Southall And Brent REvisited (SABRE) study, a tri-ethnic cohort study conducted in the UK. We are interested in identifying potential ethnic differences in metabolite levels and associations as well as their evolution over time, with the aim of gaining a better understanding of different risk of cardio-metabolic disorders across ethnicities. Within a Bayesian framework, we employ a nodewise regression approach to infer the structure of the graphs, borrowing information across time as well as across ethnicities. The response variables of interest are metabolite levels measured at two time points and for two ethnic groups, Europeans and South-Asians. We use nodewise regression to estimate the high-dimensional precision matrices of the metabolites, imposing sparsity on the regression coefficients through the dynamic horseshoe prior, thus favouring sparser graphs. We provide the code to fit the proposed model using the software Stan, which performs posterior inference using Hamiltonian Monte Carlo sampling, as well as a detailed description of a block Gibbs sampling scheme.

6.
Trials ; 24(1): 736, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37974284

RESUMO

BACKGROUND: Electroencephalography (EEG)-based brain-computer interfaces (BCIs) allow to modulate the sensorimotor rhythms and are emerging technologies for promoting post-stroke motor function recovery. The Promotoer study aims to assess the short and long-term efficacy of the Promotoer system, an EEG-based BCI assisting motor imagery (MI) practice, in enhancing post-stroke functional hand motor recovery. This paper details the statistical analysis plan of the Promotoer study. METHODS: The Promotoer study is a randomized, controlled, assessor-blinded, single-centre, superiority trial, with two parallel groups and a 1:1 allocation ratio. Subacute stroke patients are randomized to EEG-based BCI-assisted MI training or to MI training alone (i.e. no BCI). An internal pilot study for sample size re-assessment is planned. The primary outcome is the effectiveness of the Upper Extremity Fugl-Meyer Assessment (UE-FMA) score. Secondary outcomes include clinical, functional, and user experience scores assessed at the end of intervention and at follow-up. Neurophysiological assessments are also planned. Effectiveness formulas have been specified, and intention-to-treat and per-protocol populations have been defined. Statistical methods for comparisons of groups and for development of a predictive score of significant improvement are described. Explorative subgroup analyses and methodology to handle missing data are considered. DISCUSSION: The Promotoer study will provide robust evidence for the short/long-term efficacy of the Promotoer system in subacute stroke patients undergoing a rehabilitation program. Moreover, the development of a predictive score of response will allow transferring of the Promotoer system to optimal clinical practice. By carefully describing the statistical principles and procedures, the statistical analysis plan provides transparency in the analysis of data. TRIAL REGISTRATION: ClinicalTrials.gov NCT04353297 . Registered on April 15, 2020.


Assuntos
Interfaces Cérebro-Computador , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Recuperação de Função Fisiológica/fisiologia , Reabilitação do Acidente Vascular Cerebral/métodos , Projetos Piloto , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/complicações , Extremidade Superior
7.
J Phys Chem C Nanomater Interfaces ; 127(40): 20183-20193, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37850082

RESUMO

Cerium dioxide (CeO2; ceria) nanoparticles (CeNPs) are promising nanozymes that show a variety of biological activity. Effective nanozymes need to retain their activity in the face of surface speciation in biological environments, and characterizing surface speciation is therefore critical to understanding and controlling the therapeutic capabilities of CeNPs. In particular, adsorbed phosphates can impact the enzymatic activity exploited to convert phosphate prodrugs into therapeutics in vivo and also define the early stages of the phosphate-scavenging processes that lead to the transformation of active CeO2 into inactive CePO4. In this work, we utilize ab initio lattice-dynamics calculations to study the interaction of phosphates with the three major surfaces of ceria and to predict the infrared (IR) and Raman spectral signatures of adsorbed phosphate species. We find that phosphates adsorb strongly to CeO2 surfaces in a range of stable binding configurations, of which 5-fold coordinated P species in a trigonal bipyramidal coordination may represent a stable intermediate in the early stages of phosphate scavenging. We find that the phosphate species show characteristic spectral fingerprints between 500 and 1500 cm-1, whereas the bare CeO2 surfaces show no active modes above 600 cm-1, and the 5-fold coordinated P species in particular show potential diagnostic P-O stretching modes between 650 and 700 cm-1 in both IR and Raman spectra. This comprehensive exploration of different binding modes for phosphates on CeO2 and the set of reference spectra provides an important step toward the experimental characterization of phosphate speciation and, ultimately, control of its impact on the performance of ceria nanozymes.

8.
Acta Orthop ; 94: 416-425, 2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37565339

RESUMO

BACKGROUND AND PURPOSE: Antibiotic-loaded bone cement (ALBC) and systemic antibiotic prophylaxis (SAP) have been used to reduce periprosthetic joint infection (PJI) rates. We investigated the use of ALBC and SAP in primary total knee arthroplasty (TKA). PATIENTS AND METHODS: This observational study is based on 2,971,357 primary TKAs reported in 2010-2020 to national/regional joint arthroplasty registries in Australia, Denmark, Finland, Germany, Italy, the Netherlands, New Zealand, Norway, Romania, South Africa, Sweden, Switzerland, the UK, and the USA. Aggregate-level data on trends and types of bone cement, antibiotic agents, and doses and duration of SAP used was extracted from participating registries. RESULTS: ALBC was used in 77% of the TKAs with variation ranging from 100% in Norway to 31% in the USA. Palacos R+G was the most common (62%) ALBC type used. The primary antibiotic used in ALBC was gentamicin (94%). Use of ALBC in combination with SAP was common practice (77%). Cefazolin was the most common (32%) SAP agent. The doses and duration of SAP used varied from one single preoperative dosage as standard practice in Bolzano, Italy (98%) to 1-day 4 doses in Norway (83% of the 40,709 TKAs reported to the Norwegian arthroplasty register). CONCLUSION: The proportion of ALBC usage in primary TKA varies internationally, with gentamicin being the most common antibiotic. ALBC in combination with SAP was common practice, with cefazolin the most common SAP agent. The type of ALBC and type, dose, and duration of SAP varied among participating countries.


Assuntos
Artroplastia do Joelho , Infecções Relacionadas à Prótese , Humanos , Antibacterianos/uso terapêutico , Artroplastia do Joelho/efeitos adversos , Cimentos Ósseos/uso terapêutico , Cefazolina , Infecções Relacionadas à Prótese/epidemiologia , Infecções Relacionadas à Prótese/prevenção & controle , Infecções Relacionadas à Prótese/tratamento farmacológico , Gentamicinas , América do Norte , Europa (Continente) , Oceania , África
9.
Phys Chem Chem Phys ; 25(27): 18011-18022, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37377444

RESUMO

The MgO-CO2-H2O system have a variety of important industrial applications including in catalysis, immobilisation of radionuclides and heavy metals, construction, and mineralisation and permanent storage of anthropogenic CO2. Here, we develop a computational approach to generate phase stability plots for the MgO-CO2-H2O system that do not rely on traditional experimental corrections for the solid phases. We compare the predictions made by several dispersion-corrected density-functional theory schemes, and we include the temperature-dependent Gibbs free energy through the quasi-harmonic approximation. We locate the Artinite phase (Mg2CO3(OH)2·3H2O) within the MgO-CO2-H2O phase stability plot, and we demonstrate that this widely-overlooked hydrated and carbonated phase is metastable and can be stabilised by inhibiting the formation of fully-carbonated stable phases. Similar considerations may apply more broadly to other lesser known phases. These findings provide new insight to explain conflicting results from experimental studies, and demonstrate how this phase can potentially be stabilised by optimising the synthesis conditions.

10.
Bioact Mater ; 21: 547-565, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36185749

RESUMO

The disability, mortality and costs due to ionizing radiation (IR)-induced osteoporotic bone fractures are substantial and no effective therapy exists. Ionizing radiation increases cellular oxidative damage, causing an imbalance in bone turnover that is primarily driven via heightened activity of the bone-resorbing osteoclast. We demonstrate that rats exposed to sublethal levels of IR develop fragile, osteoporotic bone. At reactive surface sites, cerium ions have the ability to easily undergo redox cycling: drastically adjusting their electronic configurations and versatile catalytic activities. These properties make cerium oxide nanomaterials fascinating. We show that an engineered artificial nanozyme composed of cerium oxide, and designed to possess a higher fraction of trivalent (Ce3+) surface sites, mitigates the IR-induced loss in bone area, bone architecture, and strength. These investigations also demonstrate that our nanozyme furnishes several mechanistic avenues of protection and selectively targets highly damaging reactive oxygen species, protecting the rats against IR-induced DNA damage, cellular senescence, and elevated osteoclastic activity in vitro and in vivo. Further, we reveal that our nanozyme is a previously unreported key regulator of osteoclast formation derived from macrophages while also directly targeting bone progenitor cells, favoring new bone formation despite its exposure to harmful levels of IR in vitro. These findings open a new approach for the specific prevention of IR-induced bone loss using synthesis-mediated designer multifunctional nanomaterials.

11.
Materials (Basel) ; 15(23)2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36500167

RESUMO

This review focusses on the development of thermoelectric composites made of oxide or conventional inorganic materials, and polymers, with specific emphasis on those containing oxides. Discussion of the current state-of-the-art thermoelectric materials, including the individual constituent materials, i.e., conventional materials, oxides and polymers, is firstly presented to provide the reader with a comparison of the top-performing thermoelectric materials. Then, individual materials used in the inorganic/polymer composites are discussed to provide a comparison of the performance of the composites themselves. Finally, the addition of carbon-based compounds is discussed as a route to improving the thermoelectric performance. For each topic discussed, key thermoelectric properties are tabulated and comparative figures are presented for a wide array of materials.

12.
Acta Biomed ; 92(S3): e2021558, 2022 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-35604265

RESUMO

BACKGROUND AND AIM: High tibial osteotomies (HTO) are effective procedures to treat younger patients affected by moderate but symptomatic arthritis. Open-wedge HTO (OW-HTO) is more often performed compared to a closing wedge osteotomy to treat varus arthritis of the knee due to a lower incidence of complications and better results: lateral hinge fracture (LHF) is the most common complication of OW-HTO. Intra articular fractures of the lateral tibial plateau (Takeuchi type III) appear as a particularly serious complication due to its extension to the subchondral bone of the compartment towards which the load is shifted. Aim of our study, is to assess if an intra articular fracture of the lateral tibial plateau occurring during an OW-HTO leads to an higher risk of failure and to an early conversion to a total knee arthroplasty. METHODS: Between January 2013 and December 2018 114 patients underwent OW-HTO at our Orthopaedic Department. All the patients underwent the same surgical procedure performed by a skilled knee surgeon: a subcutaneous-medial locked plate (Tomofix®, Synthes, Solothurn, Switzerland) has been used in all the procedures to stabilize the osteotomy. Clinical and radiographic follow up has been performed at one, three, six and twelve months postoperatively afterwards annually. We retrospectively reviewed all the intra operative fluoroscopy of patients to detect those affected by an intra articular fracture of the lateral tibial plateau occurred intra operatively. RESULTS: A LHF occurred in 11 out of 114 patients (9.65%) who underwent an OW-HTO; in particular nine patients (7.9%) had a Type III LHF. In all cases such complication has been detected intra operatively. In the subgroup of patients who experienced an intra articular fracture of the tibial plateau at the last follow up only one patients underwent to a revision with a total knee arthroplasty; in other words, the survivorship of an OW-HTO complicated by a LHF type III resulted 89% at a mean follow-up of 5 years. In 103 patients without an intraoperative fracture, the percentage of patients free from revision at the last follow up resulted of 92%. CONCLUSIONS: Takeuchi type III fracture is an uncommon but serious complication to manage: in our case series we found that an early recognition and a correct treatment of this occurrence don't lead to a premature conversion to a knee arthroplasty if compared with an uncomplicated osteotomy. Further studies are necessary to establish specific subjective outcomes after OW-HTO burdened by an intra articular fracture of the lateral plateau.


Assuntos
Artroplastia do Joelho , Fraturas Intra-Articulares , Osteoartrite do Joelho , Fraturas da Tíbia , Artroplastia do Joelho/efeitos adversos , Humanos , Fraturas Intra-Articulares/cirurgia , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/cirurgia , Osteotomia/efeitos adversos , Osteotomia/métodos , Estudos Retrospectivos , Tíbia/cirurgia , Fraturas da Tíbia/diagnóstico por imagem , Fraturas da Tíbia/etiologia , Fraturas da Tíbia/cirurgia , Resultado do Tratamento
13.
Chemosphere ; 298: 134064, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35240151

RESUMO

Produced water is the wastewater formed when water is brought from subsurface reservoirs during oil or gas extraction. Currently, produced water is mainly treated using conventional trains that contain adsorbates, membrane filters, phase separators and cyclones. This paper reviewed the detailed characteristics of oilfield-produced water and the assessment of multiple technologies at primary, secondary, and tertiary treatments stages. The effectiveness of the treatment technology from the production of waste, energy requirements, usage of chemicals and the treatment effect of contaminants has been discussed. Then a qualitative assessment was presented in terms of energy requirements, robustness, flexibility, waste generation, modularity, and mobility, which has become critical to the development and application prospects of any technology.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Campos de Petróleo e Gás , Tecnologia , Eliminação de Resíduos Líquidos , Águas Residuárias/análise
14.
Diagnostics (Basel) ; 11(12)2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34943622

RESUMO

Insanity defense is sometimes invoked in criminal cases, and its demonstration is usually based on a multifactorial contribution of behavioural, clinical, and neurological elements. Neuroradiological evidence of structural alterations in cerebral areas that involve decision-making and moral reasoning is often accepted as a useful tool in these evaluations. On the other hand, the genetic predisposition to anti-social behavior is still controversial. In this paper, we describe two cases of violent crimes committed by young carriers of genetic variants associated with personality disorder; both the defendants claimed to be insane at the time of the crime. We discuss these cases and review the scientific literature regarding the relationship between legal incapacity/predisposition to criminal behavior and genetic mutations. In conclusion, despite some genetic variants being able to influence several cognitive processes (like moral judgement and impulse control), there is currently no evidence that carriers of these mutations are, per se, incapable of intentionally committing crimes.

15.
ACS Appl Mater Interfaces ; 13(34): 41303-41314, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34405998

RESUMO

We present a detailed theoretical investigation of the interaction of graphene with the SrO-terminated (001) surface of pristine and La-doped SrTiO3. The adsorption of graphene is thermodynamically favorable with interfacial adsorption energies of -0.08 and -0.32 J/m2 to pristine SrTiO3 and La-doped SrTiO3 surfaces, respectively. We find that graphene introduces C 2p states at the Fermi level, rendering the composite semimetallic, and thus the electrical properties are predicted to be highly sensitive to the amount and quality of the graphene. An investigation of the lattice dynamics predicts that graphene adsorption may lead to a 60-90% reduction in the thermal conductivity due to a reduction in the phonon group velocities, accounting for the reduced thermal conductivity of the composite materials observed experimentally. This effect is enhanced by La doping. We also find evidence that both La dopant ions and adsorbed graphene introduce low-frequency modes that may scatter heat-carrying acoustic phonons, and that, if present, these effects likely arise from stronger phonon-phonon interactions.

16.
Front Neurol ; 12: 700472, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34295303

RESUMO

Background: Crutches are the most common walking aids prescribed to improve mobility in subjects with central nervous system (CNS) lesions. To increase adherence to the appropriate level of crutch usage, providing load-related auditory feedback (aFB) may be a useful approach. We sensorized forearm crutches and developed a custom software to provide aFB information to both user and physical therapist (PhT). Aim: Evaluate aFB effects on load control during gait by a self-controlled case series trial. Methods: A single experimental session was conducted enrolling 12 CNS lesioned participants. Load on crutch was recorded during 10 Meter Walk Test performed with and without aFB. In both cases, crutch load data, and gait speed were recorded. Usability and satisfaction questionnaires were administered to participants and PhTs involved. Results: Reliable data were obtained from eight participants. Results showed that compared to the no FB condition, aFB yielded a significant reduction in the mean load on the crutches during gait (p = 0.001). The FB did not influence gait speed or fatigue (p > 0.05). The experience questionnaire data indicated a positive experience regarding the use of aFB from both participants' and PhTs' perspectives. Conclusion: aFB significantly improves compliance with crutch use and does not affect gait speed or fatigue by improving the load placed on crutches. The FB is perceived by users as helpful, safe, and easy to learn, and does not interfere with attention or concentration while walking. Furthermore, the PhTs consider the system to be useful, easy to learn and reliable.

17.
Cortex ; 138: 101-112, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33677324

RESUMO

Clinical studies described emotional and social behaviour alterations in patients with cerebellar diseases, proposing a role of specific cerebello-cerebral circuits in social cognition. However, for a long time these difficulties were underestimated, and no studies have addressed the correlation between social cognition deficits and topography of the cerebellar damage. The present study aims to investigate the social cognition impairment and the neuroanatomical alterations in patients with spinocerebellar ataxia type 2 (SCA2) and to analyze their relationship. To this purpose a social cognition battery composed by three tests, and a MRI protocol were administered to 13 SCA2 patients and 26 healthy subjects. The pattern of gray matter (GM) atrophy was analyzed by voxel-based morphometry, and the GM volumes of each altered area were correlated with the behavioral scores to investigate anatomo-functional relationships. In addition, we investigated the relationship between social deficits and damage to the cerebellar peduncles using DTI diffusivity indices. Our patients showed impairment of the immediate perceptual component of the mental state recognition (i.e., to recognize feelings and thoughts from the eyes expression), and difficulties in anger attribution, and in the understanding of false or mistaken beliefs. They showed a pattern of GM reduction in cerebellar regions, including lobules IX and VIIIb and Crus II, all of which are involved in specific components of the mentalizing process. Interestingly, the behavioral performance, in which SCA2 patients showed impairments compared to controls, correlated with the degree of cerebellar GM reduction and with the presence of microstructural abnormalities in the cerebellar peduncles. The present study provides the first characterization of the social cognition deficits in a homogenous cohort SCA2 patients and demonstrates that alterations in specific cerebellar regions should represent the neurobiological underpinning of their social behavior difficulties. Our results offer a new point of view in considering these aspects in the clinical practice.


Assuntos
Cognição Social , Ataxias Espinocerebelares , Cerebelo/diagnóstico por imagem , Substância Cinzenta , Humanos , Imageamento por Ressonância Magnética , Ataxias Espinocerebelares/complicações
18.
Disabil Rehabil ; 43(11): 1576-1584, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-31588811

RESUMO

PURPOSE: To examine physiological responses and perceived exertion during robot-assisted treadmill walking in non-ambulatory stroke survivors; compare these outcomes with aerobic exercise recommendations; and investigate the effect of robotic assistance. MATERIALS AND METHODS: Twelve non-ambulatory stroke survivors (67 ± 11 years-old, 84 ± 38 d post-stroke) participated. Subjects walked three times 20 min (1 session/day) in the Lokomat: once with conventional exercise parameters, once with 60% robotic assistance and once with 100% robotic assistance. Gas exchange and heart rate were monitored continuously. Perceived exertion was assessed every 3 min during walking. RESULTS: During conventional robot-assisted treadmill walking, net perceived exertion (0-14 scale) significantly increased between minute 6 (median = 2, interquartile range = 4) and 18 (median = 5, interquartile range = 4). Net physiological responses did not significantly change over time. Throughout exercise, percentage of predicted heart rate reserve was significantly below the 40% threshold (medians: 11-14%) and percentage of predicted maximum heart rate reached the 55% threshold (medians: 59-60%). Perceived exertion reached the 11-point threshold halfway. Net physiological responses and perceived exertion did not significantly differ between 60% and 100% robotic assistance. CONCLUSIONS: The assistance level that non-ambulatory stroke survivors require at their highest tolerable walking speed seems too high to sufficiently stress the cardiorespiratory system during robot-assisted treadmill walking.Implications for rehabilitationThe exercise intensity of 20-minute conventional robot-assisted treadmill walking can be low, and might be too low to challenge the cardiorespiratory system of non-ambulatory stroke survivors.Lowering the level of robotic assistance from 100% to 60% does not seem to increase the exercise intensity of 20-minute robot-assisted treadmill walking.


Assuntos
Robótica , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Idoso , Teste de Esforço , Humanos , Pessoa de Meia-Idade , Esforço Físico , Sobreviventes , Caminhada
19.
Front Neurol ; 11: 584317, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33162930

RESUMO

Objective: The aim of the present observational study is to report on the data from a large sample of inpatients, clinical staff and other workers at an Italian neurorehabilitation hospital dealing with SARS-CoV-2 infections, in order to analyze how it might have affected the management and the effectiveness of neurorehabilitation. Methods: The data on infection monitoring, obtained by 2,192 swabs, were reported and compared among 253 patients, 722 clinical professionals and 232 other hospital workers. The number of admissions and neurorehabilitation sessions performed in the period from March-May 2020 was compared with those of the same period in 2019. Results: Four patients and three clinical professionals were positive for COVID-19 infection. Six out of these seven people were from the same ward. Several measures were taken to handle the infection, putting in place many restrictions, with a significant reduction in new admissions to the hospital (p < 0.001). However, neither the amount of neurorehabilitation for inpatients (p = 0.681) nor the effectiveness of treatments (p = 0.464) were reduced when compared to the data from 2019. Conclusions: Our data show that the number of infections was contained in our hospital, probably thanks to the protocols adopted for reducing contagion and the environmental features of our wards. This allowed inpatients to continue to safely spend more than 3 hours per day in neurorehabilitation, effectively improving their independence in the activities of daily living.

20.
Int J Biostat ; 17(1): 153-164, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32866119

RESUMO

We analyse data from the Southall And Brent REvisited (SABRE) tri-ethnic study, where measurements of metabolic and anthropometric variables have been recorded. In particular, we focus on modelling the distribution of insulin resistance which is strongly associated with the development of type 2 diabetes. We propose the use of a Bayesian nonparametric prior to model the distribution of Homeostasis Model Assessment insulin resistance, as it allows for data-driven clustering of the observations. Anthropometric variables and metabolites concentrations are included as covariates in a regression framework. This strategy highlights the presence of sub-populations in the data, characterised by different levels of risk of developing type 2 diabetes across ethnicities. Posterior inference is performed through Markov Chains Monte Carlo (MCMC) methods.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Teorema de Bayes , Estudos de Coortes , Diabetes Mellitus Tipo 2/epidemiologia , Humanos , Cadeias de Markov
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