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1.
J Cardiothorac Surg ; 19(1): 143, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504317

RESUMO

BACKGROUND: Coronary artery obstruction after percutaneous aortic replacement is a complication with high short-term mortality secondary to the lack of timely treatment. There are various predictors of coronary obstruction prior to valve placement such as the distance from the ostia, the degree of calcification, the distance from the sinuses; In such a situation some measures must be taken to prevent and treat coronary obstruction. CASE PRESENTATION: An 84-year-old male, with severe aortic stenosis and high surgical risk, who was treated with TAVR. However, during the deployment of the valve he presented hemodynamic instability secondary to LMCA obstruction. The intravascular image showed obstruction of the ostium secondary to the displacement of calcium that he was successfully treated with a chimney stent technique. CONCLUSIONS: The high degree of calcification and the left ostium near the annulus are conditions for obstruction of the ostium at the time of valve release; In this context, provisional stenting prior to TAVR in patients at high risk of obstruction should be considered as a safe prevention strategy to achieve the success of the procedure.


Assuntos
Estenose da Valva Aórtica , Calcinose , Oclusão Coronária , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Masculino , Humanos , Idoso de 80 Anos ou mais , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/métodos , Valva Aórtica/cirurgia , Vasos Coronários/cirurgia , Próteses Valvulares Cardíacas/efeitos adversos , Fatores de Risco , Resultado do Tratamento , Oclusão Coronária/etiologia , Calcinose/complicações , Calcinose/cirurgia , Estenose da Valva Aórtica/complicações , Desenho de Prótese
2.
J Neuroeng Rehabil ; 21(1): 30, 2024 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-38419069

RESUMO

BACKGROUND: Despite technical advances in the field of wearable robotic devices (WRD), there is still limited user acceptance of these technologies. While usability often comes as a key factor influencing acceptance, there is a scattered landscape of definitions and scopes for the term. To advance usability evaluation, and to integrate usability features as design requirements during technology development, there is a need for benchmarks and shared terminology. These should be easily accessible and implementable by developers. METHODS: An initial set of usability attributes (UA) was extracted from a literature survey on usability evaluation in WRD. The initial set of attributes was enriched and locally validated with seven developers of WRD through an online survey and a focus group. The locally validated glossary was then externally validated through a globally distributed online survey. RESULTS: The result is the Robotics Usability Glossary (RUG), a comprehensive glossary of 41 UA validated by 70 WRD developers from 17 countries, ensuring its generalizability. 31 of the UA had high agreement scores among respondents and 27 were considered highly relevant in the field, but only 11 of them had been included as design criteria by the respondents. CONCLUSIONS: Multiple UA ought to be considered for a comprehensive usability assessment. Usability remains inadequately incorporated into device development, indicating a need for increased awareness and end-user perspective. The RUG can be readily accessed through an online platform, the Interactive Usability Toolbox (IUT), developed to provide context-specific outcome measures and usability evaluation methods. Overall, this effort is an important step towards improving and promoting usability evaluation practices within WRD. It has the potential to pave the way for establishing usability evaluation benchmarks that further endorse the acceptance of WRD.


Assuntos
Robótica , Dispositivos Eletrônicos Vestíveis , Humanos , Interface Usuário-Computador , Inquéritos e Questionários , Grupos Focais
3.
Plant J ; 117(5): 1305-1316, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38169533

RESUMO

Seeds of the root parasitic plant Striga hermonthica undergo a conditioning process under humid and warm environments before germinating in response to host-released stimulants, particularly strigolactones (SLs). The plant hormone abscisic acid (ABA) regulates different growth and developmental processes, and stress response; however, its role during Striga seed germination and early interactions with host plants is under-investigated. Here, we show that ABA inhibited Striga seed germination and that hindering its biosynthesis induced conditioning and germination in unconditioned seeds, which was significantly enhanced by treatment with the SL analog rac-GR24. However, the inhibitory effect of ABA remarkably decreased during conditioning, confirming the loss of sensitivity towards ABA in later developmental stages. ABA measurement showed a substantial reduction of its content during the early conditioning stage and a significant increase upon rac-GR24-triggered germination. We observed this increase also in released seed exudates, which was further confirmed by using the Arabidopsis ABA-reporter GUS marker line. Seed exudates of germinated seeds, containing elevated levels of ABA, impaired the germination of surrounding Striga seeds in vitro and promoted root growth of a rice host towards germinated Striga seeds. Application of ABA as a positive control caused similar effects, indicating its function in Striga/Striga and Striga/host communications. In summary, we show that ABA is an essential player during seed dormancy and germination processes in Striga and acts as a rhizospheric signal likely to support host infestation.


Assuntos
Arabidopsis , Striga , Ácido Abscísico/farmacologia , Germinação , Striga/fisiologia , Reguladores de Crescimento de Plantas/farmacologia , Sementes
4.
JMIR Serious Games ; 12: e39286, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38180843

RESUMO

Background: New interventions based on motor learning principles and neural plasticity have been tested among patients with ataxia and hemiparesis. Therapies of pedaling exercises have also shown their potential to induce improvements in muscle activity, strength, and balance. Virtual reality (VR) has been demonstrated as an effective tool for improving the adherence to physical therapy, but it is still undetermined if it promotes greater improvements than conventional therapy. Objective: Our objective was to compare the effect on lower limb range of motion (ROM) when using VR technology for cycling exercise versus not using VR technology. Methods: A randomized controlled trial with 20 patients with ataxia and hemiparesis was carried out. The participants were divided into 2 groups: the experimental group (n=10, 50%) performed pedaling exercises using the VR system and the control group (n=10, 50%) performed pedaling exercises without using VR. Measurements of the active and passive ROM of the hip and knee joint were taken before and after a cycling intervention, which consisted of 3 sessions of the same duration but with progressively increasing speeds (4, 5, and 6 km/h). Repeated measures ANOVAs were conducted to compare the preintervention (Ti) and postintervention (Te) assessments within each group. Additionally, the improvement effect of using the VR system was analyzed by comparing the variation coefficient (Δ = 1 - [Te / Ti]) between the preintervention and postintervention assessments for each group. Group comparisons were made using independent 1-tailed t tests. Results: Significant improvements were shown in active left hip flexion (P=.03) over time, but there was no group-time interaction effect (P=.67). Passive left hip flexion (P=.93) did not show significant improvements, and similar results were observed for active and passive right hip flexion (P=.39 and P=.83, respectively). Neither assessments of knee flexion (active left: P=.06; passive left: P=.76; active right: P=.34; passive right: P=.06) nor knee extension showed significant changes (active left: P=.66; passive left: P=.92; active right: P=.12; passive right: P=.38). However, passive right knee extension (P=.04) showed a significant improvement over time. Overall, although active and passive ROM of the knee and hip joints showed a general improvement, no statistically significant differences were found between the groups. Conclusions: In this study, participants who underwent the cycling intervention using the VR system showed similar improvement in lower limb ROM to the participants who underwent conventional training. Ultimately, the VR system can be used to engage participants in physical activity.

5.
Plant J ; 117(2): 541-560, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37932864

RESUMO

Carotenoids are isoprenoid pigments indispensable for photosynthesis. Moreover, they are the precursor of apocarotenoids, which include the phytohormones abscisic acid (ABA) and strigolactones (SLs) as well as retrograde signaling molecules and growth regulators, such as ß-cyclocitral and zaxinone. Here, we show that the application of the volatile apocarotenoid ß-ionone (ß-I) to Arabidopsis plants at micromolar concentrations caused a global reprogramming of gene expression, affecting thousands of transcripts involved in stress tolerance, growth, hormone metabolism, pathogen defense, and photosynthesis. This transcriptional reprogramming changes, along with induced changes in the level of the phytohormones ABA, jasmonic acid, and salicylic acid, led to enhanced Arabidopsis resistance to the widespread necrotrophic fungus Botrytis cinerea (B.c.) that causes the gray mold disease in many crop species and spoilage of harvested fruits. Pre-treatment of tobacco and tomato plants with ß-I followed by inoculation with B.c. confirmed the effect of ß-I in increasing the resistance to this pathogen in crop plants. Moreover, we observed reduced susceptibility to B.c. in fruits of transgenic tomato plants overexpressing LYCOPENE ß-CYCLASE, which contains elevated levels of endogenous ß-I, providing a further evidence for its effect on B.c. infestation. Our work unraveled ß-I as a further carotenoid-derived regulatory metabolite and indicates the possibility of establishing this natural volatile as an environmentally friendly bio-fungicide to control B.c.


Assuntos
Arabidopsis , Norisoprenoides , Solanum lycopersicum , Reguladores de Crescimento de Plantas/metabolismo , Arabidopsis/metabolismo , Resistência à Doença/genética , Transcriptoma , Ácido Abscísico , Botrytis/metabolismo , Plantas Geneticamente Modificadas/genética , Doenças das Plantas/microbiologia , Regulação da Expressão Gênica de Plantas
6.
PLoS One ; 18(12): e0295413, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38060602

RESUMO

The hippocampus is a fundamental cortical structure in the memory process of encoding, retaining, and recalling information. Transcranial Magnetic Stimulation (TMS) following a Paired Associative Stimulation (PAS) enhances nervous system excitability and promotes cortical plasticity mechanisms by synchronizing two stimuli in the same neural pathway. However, PAS has not been shown to improve memorization capacity yet. Here, we present an innovative protocol stemming from the PAS paradigm, which combines single-pulse TMS to the hippocampus with endogenous hippocampal activity during a working memory (WM) task. 96 volunteers were randomized across one experimental group and three parallel groups (motor cortex stimulation, sham stimulation, and no stimulation) in a single session. This combined-stimuli configuration resulted in an increased memorization capacity in the WM task, which was dependent on the stimulated brain location and subjects' basal memory performance. These results are potentially significant for clinical research on memory dysfunction and its related neurological disorders. Future research on paired associative or combined stimulation is required to unveil stimulation-derived neural mechanisms that enhance the ability to memorize.


Assuntos
Plasticidade Neuronal , Estimulação Magnética Transcraniana , Humanos , Encéfalo , Potencial Evocado Motor/fisiologia , Hipocampo , Plasticidade Neuronal/fisiologia , Estimulação Magnética Transcraniana/métodos
7.
Artigo em Inglês | MEDLINE | ID: mdl-38083092

RESUMO

Idiopathic Parkinson's disease (PD) is the second most common neurodegenerative disorder worldwide. It affects the nervous system, causing motor and non-motor symptomatology. However, its clinical diagnosis remains dependent on the expertise of clinicians, as perceptual clinical scales are often used. Gait stability is one of the most relevant motor signs in PD. Nonetheless, it is usually not reported or quantified, possibly due to its unclear meaning and the high variability of metrics used in the literature. This work aims to identify a reliable and objective indicator that clinicians can use to assess patients in realistic contexts. We focused on the Largest Lyapunov Exponent (LLE), being the most common metric used in previous research works to quantify gait stability. The short and long-term LLEs were calculated in a group of 34 healthy and 42 participants diagnosed with PD. The long-term LLE extracted from the chest, right arm and right foot sensors showed statistical differences between subjects with PD and healthy control (HC) subjects, showing that the HC subjects are more stable than PD patients, whereas the short-term LLE showed the opposite results. Further investigation is required to clarify the reliability of this metric to detect and rate gait stability in people affected with PD.Clinical Relevance- This study is the first step towards the identification of an objective methodology to assess gait stability in clinical settings. Achieving this goal will contribute to improve the understanding and support the diagnosis of gait disorders that cause gait stability problems.


Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/diagnóstico , Reprodutibilidade dos Testes , Marcha/fisiologia , , Braço
8.
Sci Rep ; 13(1): 22908, 2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129592

RESUMO

Hemiparetic gait is the most common motor-disorder after stroke and, in spite of rehabilitation efforts, it is persistent in 50% of community dwelling stroke-survivors. Robotic exoskeletons have been proposed as assistive devices to support impaired joints. An example of these devices is the REFLEX knee exoskeleton, which assists the gait of hemiparetic subjects and whose action seems to be properly embodied by stroke survivors, who were able to adapt the motion of their non-assisted limbs and, therefore, reduce their compensation mechanisms. This paper presents an experimental validation carried out to deepen into the effects of REFLEX's assistance in hemiparetic subjects. Special attention was paid to the effect produced in the muscular activity as a metric to evaluate the embodiment of this technology. Significant differences were obtained at the subject level due to the assistance; however, the high dispersion of the measured outcomes avoided extracting global effects at the group level. These results highlight the need of individually tailoring the action of the robot to the individual needs of each patient to maximize the beneficial outcomes. Extra research effort should be done to elucidate the neural mechanisms involved in the embodiment of external devices by stroke survivors.


Assuntos
Exoesqueleto Energizado , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/complicações , Marcha , Reflexo
9.
IEEE Int Conf Rehabil Robot ; 2023: 1-6, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37941171

RESUMO

Powered lower limb exoskeletons have been used in recent decades to support and improve conventional gait rehabilitation programs. In this context, visual feedback is considered a valuable tool to facilitate patient learning and engagement. Treadmill-based lower limb robotic exoskeletons are commonly incorporated with traditional screens or virtual reality (VR) devices. However, these modalities are incompatible with over-ground robotic exoskeletons, in which users should pay attention to multiple elements of the open environment and more complex tasks. Recent advances in augmented reality (AR) technology have unlocked a new way of displaying 3D graphics in untethered wearable devices like Microsoft's Hololens 2 without occluding the rest of the user's field of view. These advances can be crucial in certain situations and position AR as an excellent candidate to improve visual feedback when using robotic exoskeletons. In this work, we present the development of an AR-based audio-visual feedback system that tracks the trunk rotation from an Inertial Measurement Unit (IMU) to aid in walking tasks assisted by a lower limb robotic exoskeleton. A preliminary study was done integrating the H3 robotic exoskeleton with Hololens 2. We observed that displaying posture information is feasible and could help mitigate the unnatural posture often imposed by a robotic exoskeleton.


Assuntos
Realidade Aumentada , Exoesqueleto Energizado , Humanos , Estudos de Viabilidade , Retroalimentação , Caminhada , Marcha
10.
IEEE Int Conf Rehabil Robot ; 2023: 1-6, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37941226

RESUMO

The objective and quantitative assessment of physical human-exoskeletons interaction (pHEI) represents a pressing necessity in the wearable robots field. This process remains of difficult execution, especially for early stage devices, in which the inclusion of human testing could pose ethical and safety concerns. This manuscript proposes a methodology for pHEI assessment based on an active dummy leg named Leg Replica, which is able to sense interaction forces while wearing an exoskeleton. We tested this methodology on a wearable active knee exoskeleton prototype, with the goal to evaluate the effects of a misalignment compensation mechanism. Through this methodology, it was possible to show how the misalignment compensation mechanism was able to reduce the interaction forces during passive exoskeleton motion. Such reduction was less evident when the exoskeleton was active. The tests allowed to identify specific points of improvements for the exoskeleton, enabling a more specific upgrade of the device based on these experimental results. This study demonstrates the ability of the proposed methodology to objectively benchmark different aspects of pHEI, and to accelerate the iterative development of new devices prior to human testing.


Assuntos
Exoesqueleto Energizado , Procedimentos Cirúrgicos Robóticos , Robótica , Humanos , Perna (Membro) , Joelho
11.
Eur Heart J Case Rep ; 7(11): ytad554, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38034936

RESUMO

Background: The treatment of choice for patients with severe symptomatic pure native aortic valve regurgitation (PNAVR) is surgical aortic valve replacement (SAVR). However, not all patients are candidates for surgery because of comorbidities or are deemed high risk for surgery. In such cases, transcatheter aortic valve replacement (TAVR) has proved to be better than medical treatment. Case summary: A 78-year-old male with a history of ankylosing spondylitis was admitted with New York Heart Association III heart failure. The echocardiogram showed severe aortic regurgitation and a left ventricular ejection fraction of 52%. Because of high surgical risk and being refractory to medical RX, he was accepted for TAVR. The tomography of anatomical characteristics reported the absence of calcium and dilation of the aortic ring and aortic root. During the TAVR procedure, the patient experienced valve migration, but it was autonomously repositioned in the aortic annulus. As a rescue measure, a second valve was placed. Here, we present a case of valve migration to the left ventricle treated with a valve-in-valve procedure without the need for surgical treatment. Discussion: The absence of annulus calcification in PNAVR increases the risk of post-TAVR paravalvular leak and device embolization. Valve migration generally requires valve recovery and conversion to SAVR.

12.
J Neuroeng Rehabil ; 20(1): 149, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37936173

RESUMO

Effective communication is especially important in the wearable robots (WRs) community, which encloses a great variety of devices across different application domains, e.g., healthcare, occupational, and consumer. In this paper we present a vocabulary of terms with the aim to create a common understanding of terms and concepts among the different fields of expertise relevant in the WRs community. Our goal is to develop shared documentation that could serve as a reference to facilitate the use of accepted definitions in the field. The presented vocabulary is the result of different focus group discussions among experts in the field. The resulting document was then validated by presenting it to the WR community through an online survey. The results of the survey highlight a strong agreement in terms of acceptance of the vocabulary, its usefulness, and applicability of the proposed definitions as well as an overall appreciation for its purpose and target. This work represents a pilot study providing unique material for the WR community, encouraging the use of shared agreed definitions. The reported version of the vocabulary has been made available as a live document in a github repository, for public commenting and further improvements.


Assuntos
Dispositivos Eletrônicos Vestíveis , Humanos , Projetos Piloto , Grupos Focais , Inquéritos e Questionários
13.
J Neuroeng Rehabil ; 20(1): 138, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37848992

RESUMO

OBJECTIVE: We aim to determine a comprehensive set of requirements, perceptions, and expectations that people with spinal cord injury (SCI) and the clinicians in charge of their rehabilitation have regarding the use of wearable robots (WR) for gait rehabilitation. BACKGROUND: There are concerns due to the limited user acceptance of WR for gait rehabilitation. Developers need to emphasize understanding the needs and constraints of all stakeholders involved, including the real-life dynamics of rehabilitation centers. METHODS: 15 people with SCI, 9 without experience with WR and 6 with experience with these technologies, and 10 clinicians from 3 rehabilitation centers in Spain were interviewed. A directed content analysis approach was used. RESULTS: 78 codes grouped into 9 categories (physical results, usability, psychology-related codes, technical characteristics, activities, acquisition issues, context of use, development of the technologies and clinical rehabilitation context) were expressed by at least 20% of the users interviewed, of whom 16 were not found in the literature. The agreement percentage between each group and subgroup included in the study, calculated as the number of codes that more than 20% of both groups expressed, divided over the total amount of codes any of those two groups agreed on (≥ 20%), showed limited agreement between patients and clinicians (50.00%) and between both types of patients (55.77%). The limited accessibility and availability of lower limb exoskeletons for gait rehabilitation arose in most of the interviews. CONCLUSIONS: The limited agreement percentage between patients and clinicians indicates that including both types of users in the design process of these technologies is important, given that their requirements are complementary. Engaging users with prior technology experience is recommended, as they often exhibit strong internal consensus and articulate well-defined requirements. This study adds up the knowledge available in the literature and the new codes found in our data, which enlighten important aspects that ought to be addressed in the field to develop technologies that respond to users' needs, are usable and feasible to implement in their intended contexts. APPLICATION: The set of criteria summarized in our study will be useful to guide the design, development, and evaluation of WR for gait rehabilitation to meet user's needs and allow them to be implemented in their intended context of use.


Assuntos
Exoesqueleto Energizado , Traumatismos da Medula Espinal , Dispositivos Eletrônicos Vestíveis , Humanos , Traumatismos da Medula Espinal/reabilitação , Marcha , Extremidade Inferior
14.
J Neuroeng Rehabil ; 20(1): 141, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37872633

RESUMO

BACKGROUND: Electromyography (EMG) is a classical technique used to record electrical activity associated with muscle contraction and is widely applied in Biomechanics, Biomedical Engineering, Neuroscience and Rehabilitation Robotics. Determining muscle activation onset timing, which can be used to infer movement intention and trigger prostheses and robotic exoskeletons, is still a big challenge. The main goal of this paper was to perform a review of the state-of-the-art of EMG onset detection methods. Moreover, we compared the performance of the most commonly used methods on experimental EMG data. METHODS: A total of 156 papers published until March 2022 were included in the review. The papers were analyzed in terms of application domain, pre-processing method and EMG onset detection method. The three most commonly used methods [Single (ST), Double (DT) and Adaptive Threshold (AT)] were applied offline on experimental intramuscular and surface EMG signals obtained during contractions of ankle and knee joint muscles. RESULTS: Threshold-based methods are still the most commonly used to detect EMG onset. Compared to ST and AT, DT required more processing time and, therefore, increased onset timing detection, when applied on experimental data. The accuracy of these three methods was high (maximum error detection rate of 7.3%), demonstrating their ability to automatically detect the onset of muscle activity. Recently, other studies have tested different methods (especially Machine Learning based) to determine muscle activation onset offline, reporting promising results. CONCLUSIONS: This study organized and classified the existing EMG onset detection methods to create consensus towards a possible standardized method for EMG onset detection, which would also allow more reproducibility across studies. The three most commonly used methods (ST, DT and AT) proved to be accurate, while ST and AT were faster in terms of EMG onset detection time, especially when applied on intramuscular EMG data. These are important features towards movement intention identification, especially in real-time applications. Machine Learning methods have received increased attention as an alternative to detect muscle activation onset. However, although several methods have shown their capability offline, more research is required to address their full potential towards real-time applications, namely to infer movement intention.


Assuntos
Exoesqueleto Energizado , Músculo Esquelético , Humanos , Eletromiografia/métodos , Músculo Esquelético/fisiologia , Reprodutibilidade dos Testes , Movimento/fisiologia
16.
J Heart Lung Transplant ; 42(10): 1481-1483, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37268053

RESUMO

Donation after circulatory death (DCD) is becoming increasingly utilized in heart transplantation and has the potential to further expand the donor pool. As transplant cardiologists gain more familiarity with DCD donor selection, there are many issues that lack consensus including how we incorporate the neurologic examination, how we measure functional warm ischemic time (fWIT), and what fWIT thresholds are acceptable. DCD donor selection calls for prognostication tools to help determine how quickly a donor may expire, and in current practice there is no standardization in how we make these predictions. Current scoring systems help to determine which donor may expire within a specified time window either require the temporary disconnection of ventilatory support or do not incorporate any neurologic examination or imaging. Moreover, the specified time windows differ from other DCD solid organ transplantation without standardization or strong scientific justification for these thresholds. In this perspective, we highlight the challenges faced by transplant cardiologists as they navigate the muddy waters of neuroprognostication in DCD cardiac donation. Given these difficulties, this is also a call to action for the creation of a more standardized approach to improve the DCD donor selection process for appropriate resource allocation and organ utilization.


Assuntos
Cardiologistas , Obtenção de Tecidos e Órgãos , Humanos , Morte , Doadores de Tecidos , Seleção do Doador , Sobrevivência de Enxerto
17.
J Phys Chem B ; 127(24): 5432-5444, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-37289558

RESUMO

Anthocyanins are the main active compounds in blueberry. However, they have poor oxidation stability. If anthocyanins are encapsulated in protein nanoparticles, their oxidation resistance could be increased as a result of the slowing down of the oxidation process. This work describes the advantages of using a γ-irradiated bovine serum albumin nanoparticle bound to anthocyanins. The interaction was characterized biophysically, mainly by rheology. By computational calculation and simulation based on model nanoparticles, we estimated the number of molecules forming the albumin nanoparticles, which allowed us to infer the ratio of anthocyanin/nanoparticles. Measurements by UV-vis spectroscopy, FTIR spectroscopy, fluorescence spectroscopy, dynamic light scattering (DLS), ζ potential, electron transmission microscopy, and rheology at room (25 °C) and physiological (37 °C) temperatures were performed. The spectroscopy measurements allowed identifying additional hydrophobic sites created during the irradiation process of the nanoparticle. On the basis of the rheological studies, it was observed that the BSA-NP trend is a Newtonian flow behavior type for all the temperatures selected, and there is a direct correlation between dynamic viscosity and temperature values. Furthermore, when anthocyanins are added, the system increases its resistance to the flow as reflected in the morphological changes observed by TEM, thus confirming the relationship between viscosity values and aggregate formation.


Assuntos
Antocianinas , Nanopartículas , Nanopartículas/química , Soroalbumina Bovina/química , Espectrometria de Fluorescência , Oxirredução
18.
Plant J ; 115(5): 1214-1230, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37219088

RESUMO

Identification of protein interactors is ideally suited for the functional characterization of small molecules. 3',5'-cAMP is an evolutionary ancient signaling metabolite largely uncharacterized in plants. To tap into the physiological roles of 3',5'-cAMP, we used a chemo-proteomics approach, thermal proteome profiling (TPP), for the unbiased identification of 3',5'-cAMP protein targets. TPP measures shifts in the protein thermal stability upon ligand binding. Comprehensive proteomics analysis yielded a list of 51 proteins significantly altered in their thermal stability upon incubation with 3',5'-cAMP. The list contained metabolic enzymes, ribosomal subunits, translation initiation factors, and proteins associated with the regulation of plant growth such as CELL DIVISION CYCLE 48. To functionally validate obtained results, we focused on the role of 3',5'-cAMP in regulating the actin cytoskeleton suggested by the presence of actin among the 51 identified proteins. 3',5'-cAMP supplementation affected actin organization by inducing actin-bundling. Consistent with these results, the increase in 3',5'-cAMP levels, obtained either by feeding or by chemical modulation of 3',5'-cAMP metabolism, was sufficient to partially rescue the short hypocotyl phenotype of the actin2 actin7 mutant, severely compromised in actin level. The observed rescue was specific to 3',5'-cAMP, as demonstrated using a positional isomer 2',3'-cAMP, and true for the nanomolar 3',5'-cAMP concentrations reported for plant cells. In vitro characterization of the 3',5'-cAMP-actin pairing argues against a direct interaction between actin and 3',5'-cAMP. Alternative mechanisms by which 3',5'-cAMP would affect actin dynamics, such as by interfering with calcium signaling, are discussed. In summary, our work provides a specific resource, 3',5'-cAMP interactome, as well as functional insight into 3',5'-cAMP-mediated regulation in plants.


Assuntos
Citoesqueleto de Actina , Actinas , Actinas/metabolismo , Citoesqueleto de Actina/metabolismo , Plantas/metabolismo , Sinalização do Cálcio
19.
Front Bioeng Biotechnol ; 11: 1079027, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37008040

RESUMO

Background: Reduced function of ankle muscles usually leads to impaired gait. Motorized ankle foot orthoses (MAFOs) have shown potential to improve neuromuscular control and increase volitional engagement of ankle muscles. In this study, we hypothesize that specific disturbances (adaptive resistance-based perturbations to the planned trajectory) applied by a MAFO can be used to adapt the activity of ankle muscles. The first goal of this exploratory study was to test and validate two different ankle disturbances based on plantarflexion and dorsiflexion resistance while training in standing still position. The second goal was to assess neuromuscular adaptation to these approaches, namely, in terms of individual muscle activation and co-activation of antagonists. Methods: Two ankle disturbances were tested in ten healthy subjects. For each subject, the dominant ankle followed a target trajectory while the contralateral leg was standing still: a) dorsiflexion torque during the first part of the trajectory (Stance Correlate disturbance-StC), and b) plantarflexion torque during the second part of the trajectory (Swing Correlate disturbance-SwC). Electromyography was recorded from the tibialis anterior (TAnt) and gastrocnemius medialis (GMed) during MAFO and treadmill (baseline) trials. Results: GMed (plantarflexor muscle) activation decreased in all subjects during the application of StC, indicating that dorsiflexion torque did not enhance GMed activity. On the other hand, TAnt (dorsiflexor muscle) activation increased when SwC was applied, indicating that plantarflexion torque succeeded in enhancing TAnt activation. For each disturbance paradigm, there was no antagonist muscle co-activation accompanying agonist muscle activity changes. Conclusion: We successfully tested novel ankle disturbance approaches that can be explored as potential resistance strategies in MAFO training. Results from SwC training warrant further investigation to promote specific motor recovery and learning of dorsiflexion in neural-impaired patients. This training can potentially be beneficial during intermediate phases of rehabilitation prior to overground exoskeleton-assisted walking. Decreased activation of GMed during StC might be attributed to the unloaded body weight in the ipsilateral side, which typically decreases activation of anti-gravity muscles. Neural adaptation to StC needs to be studied thoroughly in different postures in futures studies.

20.
Front Public Health ; 11: 979225, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36992891

RESUMO

Introduction: Social robots are accompanied by high expectations of what they can bring to society and in the healthcare sector. So far, promising assumptions have been presented about how and where social robots are most relevant. We know that the industry has used robots for a long time, but what about social uptake outside industry, specifically, in the healthcare sector? This study discusses what trends are discernible, to better understand the gap between technology readiness and adoption of interactive robots in the welfare and health sectors in Europe. Methods: An assessment of interactive robot applications at the upper levels of the Technology Readiness Level scale is combined with an assessment of adoption potential based on Rogers' theory of diffusion of innovation. Most robot solutions are dedicated to individual rehabilitation or frailty and stress. Fewer solutions are developed for managing welfare services or public healthcare. Results: The results show that while robots are ready from the technological point of view, most of the applications had a low score for demand according to the stakeholders. Discussion: To enhance social uptake, a more initiated discussion, and more studies on the connections between technology readiness and adoption and use are suggested. Applications being available to users does not mean they have an advantage over previous solutions. Acceptance of robots is also heavily dependent on the impact of regulations as part of the welfare and healthcare sectors in Europe.


Assuntos
Robótica , Robótica/métodos , Tecnologia , Europa (Continente)
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