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1.
Front Neurosci ; 18: 1271831, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38550567

RESUMO

Riemannian geometry-based classification (RGBC) gained popularity in the field of brain-computer interfaces (BCIs) lately, due to its ability to deal with non-stationarities arising in electroencephalography (EEG) data. Domain adaptation, however, is most often performed on sample covariance matrices (SCMs) obtained from EEG data, and thus might not fully account for components affecting covariance estimation itself, such as regional trends. Detrended cross-correlation analysis (DCCA) can be utilized to estimate the covariance structure of such signals, yet it is computationally expensive in its original form. A recently proposed online implementation of DCCA, however, allows for its fast computation and thus makes it possible to employ DCCA in real-time applications. In this study we propose to replace the SCM with the DCCA matrix as input to RGBC and assess its effect on offline and online BCI performance. First we evaluated the proposed decoding pipeline offline on previously recorded EEG data from 18 individuals performing left and right hand motor imagery (MI), and benchmarked it against vanilla RGBC and popular MI-detection approaches. Subsequently, we recruited eight participants (with previous BCI experience) who operated an MI-based BCI (MI-BCI) online using the DCCA-enhanced Riemannian decoder. Finally, we tested the proposed method on a public, multi-class MI-BCI dataset. During offline evaluations the DCCA-based decoder consistently and significantly outperformed the other approaches. Online evaluation confirmed that the DCCA matrix could be computed in real-time even for 22-channel EEG, as well as subjects could control the MI-BCI with high command delivery (normalized Cohen's κ: 0.7409 ± 0.1515) and sample-wise MI detection (normalized Cohen's κ: 0.5200 ± 0.1610). Post-hoc analysis indicated characteristic connectivity patterns under both MI conditions, with stronger connectivity in the hemisphere contralateral to the MI task. Additionally, fractal scaling exponent of neural activity was found increased in the contralateral compared to the ipsilateral motor cortices (C4 and C3 for left and right MI, respectively) in both classes. Combining DCCA with Riemannian geometry-based decoding yields a robust and effective decoder, that not only improves upon the SCM-based approach but can also provide relevant information on the neurophysiological processes behind MI.

2.
PNAS Nexus ; 3(2): pgae076, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38426121

RESUMO

Subject training is crucial for acquiring brain-computer interface (BCI) control. Typically, this requires collecting user-specific calibration data due to high inter-subject neural variability that limits the usability of generic decoders. However, calibration is cumbersome and may produce inadequate data for building decoders, especially with naïve subjects. Here, we show that a decoder trained on the data of a single expert is readily transferrable to inexperienced users via domain adaptation techniques allowing calibration-free BCI training. We introduce two real-time frameworks, (i) Generic Recentering (GR) through unsupervised adaptation and (ii) Personally Assisted Recentering (PAR) that extends GR by employing supervised recalibration of the decoder parameters. We evaluated our frameworks on 18 healthy naïve subjects over five online sessions, who operated a customary synchronous bar task with continuous feedback and a more challenging car racing game with asynchronous control and discrete feedback. We show that along with improved task-oriented BCI performance in both tasks, our frameworks promoted subjects' ability to acquire individual BCI skills, as the initial neurophysiological control features of an expert subject evolved and became subject specific. Furthermore, those features were task-specific and were learned in parallel as participants practiced the two tasks in every session. Contrary to previous findings implying that supervised methods lead to improved online BCI control, we observed that longitudinal training coupled with unsupervised domain matching (GR) achieved similar performance to supervised recalibration (PAR). Therefore, our presented frameworks facilitate calibration-free BCIs and have immediate implications for broader populations-such as patients with neurological pathologies-who might struggle to provide suitable initial calibration data.

3.
Front Genet ; 15: 1352063, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38450199

RESUMO

Introduction: TULP1 exemplifies the remarkable clinical and genetic heterogeneity observed in inherited retinal dystrophies. Our research describes the clinical and molecular characteristics of a patient manifesting an atypical retinal dystrophy pattern, marked by the identification of both a previously unreported and a rarely encountered TULP1 variant. Methods: Whole-exome sequencing was performed to identify potential causative variants. The pathogenicity of the identified TULP1 variants was evaluated through in silico predictors and a minigene splice assay, specifically designed to assess the effect of the unreported TULP1 variant. Results: We identified two TULP1 gene variants in a patient exhibiting unusual and symmetrical alterations in both retinas, characterized by an increase in autofluorescence along the distribution of retinal vessels. These variants included a known rare missense variant, c.1376T>C, and a novel splice site variant, c.822G>T. For the latter variant (c.822G>T), we conducted a minigene splice assay that demonstrated the incorporation of a premature stop codon. This finding suggests a likely activation of the nonsense-mediated mRNA decay mechanism, ultimately resulting in the absence of protein production from this allele. Segregation analysis confirmed that these variants were in trans. Discussion: Our data support that individuals with biallelic TULP1 variants may present with a unique pattern of macular degeneration and periarteriolar vascular pigmentation. This study highlights the importance of further clinical and molecular characterization of TULP1 variants to elucidate genotype-phenotype correlations in the context of inherited retinal dystrophies.

4.
JBMR Plus ; 8(2): ziae006, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38505526

RESUMO

Tissue-nonspecific alkaline phosphatase (TNALP) is a glycoprotein expressed by osteoblasts that promotes bone mineralization. TNALP catalyzes the hydrolysis of the mineralization inhibitor inorganic pyrophosphate and ATP to provide inorganic phosphate, thus controlling the inorganic pyrophosphate/inorganic phosphate ratio to enable the growth of hydroxyapatite crystals. N-linked glycosylation of TNALP is essential for protein stability and enzymatic activity and is responsible for the presence of different bone isoforms of TNALP associated with functional and clinical differences. The site-specific glycosylation profiles of TNALP are, however, elusive. TNALP has 5 potential N-glycosylation sites located at the asparagine (N) residues 140, 230, 271, 303, and 430. The objective of this study was to reveal the presence and structure of site-specific glycosylation in TNALP expressed in osteoblasts. Calvarial osteoblasts derived from Alpl+/- expressing SV40 Large T antigen were transfected with soluble epitope-tagged human TNALP. Purified TNALP was analyzed with a lectin microarray, matrix-assisted laser desorption/ionization-time of flight mass spectrometry, and liquid chromatography with tandem mass spectrometry. The results showed that all sites (n = 5) were fully occupied predominantly with complex-type N-glycans. High abundance of galactosylated biantennary N-glycans with various degrees of sialylation was observed on all sites, as well as glycans with no terminal galactose and sialic acid. Furthermore, all sites had core fucosylation except site N271. Modelling of TNALP, with the protein structure prediction software ColabFold, showed possible steric hindrance by the adjacent side chain of W270, which could explain the absence of core fucosylation at N271. These novel findings provide evidence for N-linked glycosylation on all 5 sites of TNALP, as well as core fucosylation on 4 out of 5 sites. We anticipate that this new knowledge can aid in the development of functional and clinical assays specific for the TNALP bone isoforms.

5.
Biochim Biophys Acta Biomembr ; 1866(4): 184292, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342362

RESUMO

Ecto-nucleotide pyrophosphatase/phosphodiesterase 1 (NPP1) is an enzyme present in matrix vesicles (MV). NPP1 participates on the regulation of bone formation by producing pyrophosphate (PPi) from adenosine triphosphate (ATP). Here, we have used liposomes bearing dipalmitoylphosphatidylcholine (DPPC), sphingomyelin (SM), and cholesterol (Chol) harboring NPP1 to mimic the composition of MV lipid rafts to investigate ionic and lipidic influence on NPP1 activity and mineral propagation. Atomic force microscopy (AFM) revealed that DPPC-liposomes had spherical and smooth surface. The presence of SM and Chol elicited rough and smooth surface, respectively. NPP1 insertion produced protrusions in all the liposome surface. Maximum phosphodiesterase activity emerged at 0.082 M ionic strength, whereas maximum phosphomonohydrolase activity arose at low ionic strength. Phosphoserine-Calcium Phosphate Complex (PS-CPLX) and amorphous calcium-phosphate (ACP) induced mineral propagation in DPPC- and DPPC:SM-liposomes and in DPPC:Chol-liposomes, respectively. Mineral characterization revealed the presence of bands assigned to HAp in the mineral propagated by NPP1 harbored in DPPC-liposomes without nucleators or in DPPC:Chol-liposomes with ACP nucleators. These data show that studying how the ionic and lipidic environment affects NPP1 properties is important, especially for HAp obtained under controlled conditions in vitro.


Assuntos
Lipossomos , Diester Fosfórico Hidrolases , Monoéster Fosfórico Hidrolases , Fosfatos de Cálcio/química , Íons , Lipossomos/química , Minerais , Diester Fosfórico Hidrolases/química , Diester Fosfórico Hidrolases/metabolismo , Esfingomielinas , Pirofosfatases/química , Pirofosfatases/metabolismo
6.
J Neural Eng ; 21(2)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38386506

RESUMO

Objective.A key challenge of virtual reality (VR) applications is to maintain a reliable human-avatar mapping. Users may lose the sense of controlling (sense of agency), owning (sense of body ownership), or being located (sense of self-location) inside the virtual body when they perceive erroneous interaction, i.e. a break-in-embodiment (BiE). However, the way to detect such an inadequate event is currently limited to questionnaires or spontaneous reports from users. The ability to implicitly detect BiE in real-time enables us to adjust human-avatar mapping without interruption.Approach.We propose and empirically demonstrate a novel brain computer interface (BCI) approach that monitors the occurrence of BiE based on the users' brain oscillatory activity in real-time to adjust the human-avatar mapping in VR. We collected EEG activity of 37 participants while they performed reaching movements with their avatar with different magnitude of distortion.Main results.Our BCI approach seamlessly predicts occurrence of BiE in varying magnitude of erroneous interaction. The mapping has been customized by BCI-reinforcement learning (RL) closed-loop system to prevent BiE from occurring. Furthermore, a non-personalized BCI decoder generalizes to new users, enabling 'Plug-and-Play' ErrP-based non-invasive BCI. The proposed VR system allows customization of human-avatar mapping without personalized BCI decoders or spontaneous reports.Significance.We anticipate that our newly developed VR-BCI can be useful to maintain an engaging avatar-based interaction and a compelling immersive experience while detecting when users notice a problem and seamlessly correcting it.


Assuntos
Avatar , Realidade Virtual , Humanos , Interface Usuário-Computador , Movimento , Eletroencefalografia
7.
Artigo em Inglês | MEDLINE | ID: mdl-38182020

RESUMO

BACKGROUND: An appropriate preoperative management of patients with chronic moderate to severe shoulder pain who are candidates for surgery due to rotator cuff disease or glenohumeral osteoarthritis may improve surgery and patient outcomes, but published evidence in this regard is scarce. Therefore, the availability of recommendations on preoperative interventions based on expert consensus may serve as guidance. METHODS: A Delphi study was conducted to develop a preoperative management algorithm based on a national expert consensus. A Delphi questionnaire was developed by a Scientific Committee following a systematic review using PRISMA criteria of the relevant literature published during the last 10 years. It consisted of 48 statements divided into five blocks (I. Assessment/diagnosis of preoperative pain; II. Preoperative function/psychosocial aspects; III. Therapeutic objectives; IV. Treatment; V. Follow-up/referral), and 28 experienced shoulder surgeons from across the country were invited to answer. RESULTS: All participants responded to the Delphi questionnaire in the first round and 25 in the second round (89.3% of those invited). Overall, 46/49 final statements reached a consensus, based on which a final preoperative management algorithm was defined by the Scientific Committee. First, surgeons should assess shoulder pain intensity and characteristics, shoulder functionality and psychosocial aspects using specific validated questionnaires. Preoperative therapeutic objectives should include shoulder pain control, depression/nocturnal sleep improvement, opioid consumption adjustment and substance abuse cessation. Postoperative objectives regarding the degree of shoulder pain reduction or improvement in functionality/quality of life should be established in agreement with the patient. Treatment of preoperative chronic moderate to severe shoulder pain should comprise non-pharmacological as well as pharmacological interventions. Follow-up of shoulder pain levels, treatment adherence and mental health status of these patients may be carried out by the surgical team (surgeon and anesthesiologist) together with the Primary Care team. Patients with very intense shoulder pain levels may be referred to the Pain Unit, following specific protocols. CONCLUSION: A preoperative management algorithm for patients with chronic moderate to severe shoulder pain who are candidates for surgery due to rotator cuff disease or glenohumeral osteoarthritis was defined based on a national expert consensus. Main points include a comprehensive patient management starting with an objective assessment of shoulder pain and function, quality of life, establishment of preoperative and postoperative therapeutic targets, prescription of individualized therapeutic interventions and multidisciplinary patient follow-up. Implementation of these recommendations to clinical practice may result in better preoperative shoulder pain management and more successful surgery outcomes and patient satisfaction.

8.
Pain Pract ; 24(3): 440-448, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37970746

RESUMO

BACKGROUND: Accidental dural puncture (ADP) is the most frequent major complication when performing an epidural procedure in obstetrics. Consequently, loss of pressure in the cerebrospinal fluid (CSF) leads to the development of post-dural puncture headache (PDPH), which occurs in 16%-86% of cases. To date, the efficacy of epidural fibrin patches (EFP) has not been evaluated in a controlled clinical trial, nor in comparative studies with epidural blood patches (EBP). METHODS: The objective of the present study was to compare the efficacy of EFP with respect to EBP for the treatment of refractory accidental PDPH. This prospective, randomized, open-label, parallel, comparative study included 70 puerperal women who received an EBP or EFP (35 in each group) after failure of the conventional analgesic treatment for accidental PDPH in a hospital. RESULTS: A higher percentage of women with EFP than EBP achieved complete PDPH relief after 2 (97.1% vs. 54.3%) and 12 h (100.0% vs. 65.7%) of the patch injection. The percentage of patients who needed rescue analgesia was significantly lower with EFP after 2 (2.9% vs. 48.6%) and 12 h (0.0% vs. 37.1%). After 24 h, PDPH was resolved in all women who received EFP. The recurrence of PDPH was reported in one woman from the EBP group (2.9%), who subsequently required a second patch. The mean length of hospital stay was significantly lower with EFP (3.9 days) than EBP (5.9 days). Regarding satisfaction, the mean value (Likert scale) was significantly higher with EFP (4.7 vs. 3.0). CONCLUSIONS: EFP provided better outcomes than EBP for the treatment of obstetric PDPH in terms of efficacy, safety, and patient satisfaction.


Assuntos
Cefaleia Pós-Punção Dural , Gravidez , Humanos , Feminino , Cefaleia Pós-Punção Dural/terapia , Estudos Prospectivos , Fibrina , Placa de Sangue Epidural/métodos , Manejo da Dor
9.
Indian J Palliat Care ; 29(4): 394-406, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38058484

RESUMO

Objectives: The management of chronic pain among patients with abdominal cancer is complex; against that, the neurolysis of the celiac plexus (CPN) is the best technique at the moment to determine the efficacy and safety in the treatment of chronic pain secondary to oncological pathology of the upper abdomen. Material and Methods: This was a systematic review of controlled clinical trials between 2000 and 2021, in the sources MEDLINE/PubMed, Cochrane, Scopus, Web of Science, and Google Scholar. Three independent evaluators analysed the results of the bibliographical research. The quality of the studies was assessed with the Jadad scale and the mean difference (95% confidence interval) and heterogeneity of the studies (I2) were calculated with Review Manager 5.3. Results: Seven hundred and forty-four publications were identified, including 13 studies in the qualitative synthesis and three studies in the quantitative synthesis. No difference was found in the decrease in pain intensity between 1 and 12 weeks after the intervention, comparing the experimental group with the control (P > 0.05). The adverse effects related to neurolysis were not serious and transitory, mentioning the most frequent adverse effects and reporting a percentage between 21% and 67% (with 17% for echoendoscopic neurolysis and 49% for percutaneous neurolysis). Conclusion: Celiac plexus neurolysis for the treatment of severe chronic pain secondary to oncological pathology in the upper hemiabdomen produces similar pain relief as conventional pharmacological analgesic treatment. It is a safe analgesic technique since the complications are mild and transitory.

10.
Sci Rep ; 13(1): 20163, 2023 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-37978205

RESUMO

During reaching actions, the human central nerve system (CNS) generates the trajectories that optimize effort and time. When there is an obstacle in the path, we make sure that our arm passes the obstacle with a sufficient margin. This comfort margin varies between individuals. When passing a fragile object, risk-averse individuals may adopt a larger margin by following the longer path than risk-prone people do. However, it is not known whether this variation is associated with a personalized cost function used for the individual optimal control policies and how it is represented in our brain activity. This study investigates whether such individual variations in evaluation criteria during reaching results from differentiated weighting given to energy minimization versus comfort, and monitors brain error-related potentials (ErrPs) evoked when subjects observe a robot moving dangerously close to a fragile object. Seventeen healthy participants monitored a robot performing safe, daring and unsafe trajectories around a wine glass. Each participant displayed distinct evaluation criteria on the energy efficiency and comfort of robot trajectories. The ErrP-BCI outputs successfully inferred such individual variation. This study suggests that ErrPs could be used in conjunction with an optimal control approach to identify the personalized cost used by CNS. It further opens new avenues for the use of brain-evoked potential to train assistive robotic devices through the use of neuroprosthetic interfaces.


Assuntos
Interfaces Cérebro-Computador , Eletroencefalografia , Humanos , Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Encéfalo , Algoritmos
11.
Eur Biophys J ; 52(8): 721-733, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37938350

RESUMO

Matrix vesicles are a special class of extracellular vesicles thought to actively contribute to both physiologic and pathologic mineralization. Proteomic studies have shown that matrix vesicles possess high amounts of annexin A5, suggesting that the protein might have multiple roles at the sites of calcification. Currently, Annexin A5 is thought to promote the nucleation of apatitic minerals close to the inner leaflet of the matrix vesicles' membrane enriched in phosphatidylserine and Ca2+. Herein, we aimed at unravelling a possible additional role of annexin A5 by investigating the ability of annexin A5 to adsorb on matrix-vesicle biomimetic liposomes and Langmuir monolayers made of dipalmitoylphosphatidylserine (DPPS) and dipalmitoylphosphatidylcholine (DPPC) in the absence and in the presence of Ca2+. Differential scanning calorimetry and dynamic light scattering measurements showed that Ca2+ at concentrations in the 0.5-2.0 mM range induced the aggregation of liposomes probably due to the formation of DPPS-enriched domains. However, annexin A5 avoided the aggregation of liposomes at Ca2+ concentrations lower than 1.0 mM. Surface pressure versus surface area isotherms showed that the adsorption of annexin A5 on the monolayers made of a mixture of DPPC and DPPS led to a reduction in the area of excess compared to the theoretical values, which confirmed that the protein favored attractive interactions among the membrane lipids. The stabilization of the lipid membranes by annexin A5 was also validated by recording the changes with time of the surface pressure. Finally, fluorescence microscopy images of lipid monolayers revealed the formation of spherical lipid-condensed domains that became unshaped and larger in the presence of annexin A5. Our data support the model that annexin A5 in matrix vesicles is recruited at the membrane sites enriched in phosphatidylserine and Ca2+ not only to contribute to the intraluminal mineral formation but also to stabilize the vesicles' membrane and prevent its premature rupture.


Assuntos
Anexinas , Lipossomos , Anexina A5/química , Anexina A5/metabolismo , Fosfatidilserinas/química , Fosfatidilserinas/metabolismo , Biomimética , Proteômica , Cálcio/metabolismo
13.
Cancers (Basel) ; 15(17)2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37686539

RESUMO

Acute myeloid leukemia is a complex heterogeneous disease characterized by the clonal expansion of undifferentiated myeloid precursors. Due to the difficulty in the transfection of blood cells, several hematological models have recently been developed with CRISPR/Cas9, using viral vectors. In this study, we developed an alternative strategy in order to generate CRISPR constructs by fusion PCR, which any lab equipped with basic equipment can implement. Our PCR-generated constructs were easily introduced into hard-to-transfect leukemic cells, and their function was dually validated with the addition of MYBL2 and IDH2 genes into HEK293 cells. We then successfully modified the MYBL2 gene and introduced the R172 mutation into the IDH2 gene within NB4 and HL60 cells that constitutively expressed the Cas9 nuclease. The efficiency of mutation introduction with our methodology was similar to that of ribonucleoprotein strategies, and no off-target events were detected. Overall, our strategy represents a valid and intuitive alternative for introducing desired mutations into hard-to-transfect leukemic cells without viral transduction.

14.
JCI Insight ; 8(21)2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37768732

RESUMO

Retinitis pigmentosa (RP) is the most common inherited retinal disease (IRD) and is characterized by photoreceptor degeneration and progressive vision loss. We report 4 patients presenting with RP from 3 unrelated families with variants in TBC1D32, which to date has never been associated with an IRD. To validate TBC1D32 as a putative RP causative gene, we combined Xenopus in vivo approaches and human induced pluripotent stem cell-derived (iPSC-derived) retinal models. Our data showed that TBC1D32 was expressed during retinal development and that it played an important role in retinal pigment epithelium (RPE) differentiation. Furthermore, we identified a role for TBC1D32 in ciliogenesis of the RPE. We demonstrated elongated ciliary defects that resulted in disrupted apical tight junctions, loss of functionality (delayed retinoid cycling and altered secretion balance), and the onset of an epithelial-mesenchymal transition-like phenotype. Last, our results suggested photoreceptor differentiation defects, including connecting cilium anomalies, that resulted in impaired trafficking to the outer segment in cones and rods in TBC1D32 iPSC-derived retinal organoids. Overall, our data highlight a critical role for TBC1D32 in the retina and demonstrate that TBC1D32 mutations lead to RP. We thus identify TBC1D32 as an IRD-causative gene.


Assuntos
Células-Tronco Pluripotentes Induzidas , Degeneração Retiniana , Retinose Pigmentar , Humanos , Retina , Retinose Pigmentar/genética , Degeneração Retiniana/genética , Epitélio Pigmentado da Retina , Proteínas Adaptadoras de Transdução de Sinal
15.
R Soc Open Sci ; 10(9): 230741, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37711146

RESUMO

Taxonomic identification of whale bones found during archaeological excavations is problematic due to their typically fragmented state. This difficulty limits understanding of both the past spatio-temporal distributions of whale populations and of possible early whaling activities. To overcome this challenge, we performed zooarchaeology by mass spectrometry on an unprecedented 719 archaeological and palaeontological specimens of probable whale bone from Atlantic European contexts, predominantly dating from ca 3500 BCE to the eighteenth century CE. The results show high numbers of Balaenidae (many probably North Atlantic right whale (Eubalaena glacialis)) and grey whale (Eschrichtius robustus) specimens, two taxa no longer present in the eastern North Atlantic. This discovery matches expectations regarding the past utilization of North Atlantic right whales, but was unanticipated for grey whales, which have hitherto rarely been identified in the European zooarchaeological record. Many of these specimens derive from contexts associated with mediaeval cultures frequently linked to whaling: the Basques, northern Spaniards, Normans, Flemish, Frisians, Anglo-Saxons and Scandinavians. This association raises the likelihood that early whaling impacted these taxa, contributing to their extirpation and extinction. Much lower numbers of other large cetacean taxa were identified, suggesting that what are now the most depleted whales were once those most frequently used.

16.
Bone ; 176: 116868, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37549801

RESUMO

Extracellular pyrophosphate (PPi) is well known for its fundamental role as a physiochemical mineralisation inhibitor. However, information about its direct actions on bone cells remains limited. This study shows that PPi decreased osteoclast formation and resorptive activity by ≤50 %. These inhibitory actions were associated with reduced expression of genes involved in osteoclastogenesis (Tnfrsf11a, Dcstamp) and bone resorption (Ctsk, Car2, Acp5). In osteoblasts, PPi present for the entire (0-21 days) or latter stages of culture (7-21/14-21 days) decreased bone mineralisation by ≤95 %. However, PPi present for the differentiation phase only (0-7/0-14 days) increased bone formation (≤70 %). Prolonged treatment with PPi resulted in earlier matrix deposition and increased soluble collagen levels (≤2.3-fold). Expression of osteoblast (RUNX2, Bglap) and early osteocyte (E11, Dmp1) genes along with mineralisation inhibitors (Spp1, Mgp) was increased by PPi (≤3-fold). PPi levels are regulated by tissue non-specific alkaline phosphatase (TNAP) and ecto-nucleotide pyrophosphatase/phosphodiesterase 1 (NPP1). PPi reduced NPP1 expression in both cell types whereas TNAP expression (≤2.5-fold) and activity (≤35 %) were increased in osteoblasts. Breakdown of extracellular ATP by NPP1 represents a key source of PPi. ATP release from osteoclasts and osteoblasts was decreased ≤60 % by PPi and by a selective TNAP inhibitor (CAS496014-12-2). Pertussis toxin, which prevents Gαi subunit activation, was used to investigate whether G-protein coupled receptor (GPCR) signalling mediates the effects of PPi. The actions of PPi on bone mineralisation, collagen production, ATP release, gene/protein expression and osteoclast formation were abolished or attenuated by pertussis toxin. Together these findings show that PPi, modulates differentiation, function and gene expression in osteoblasts and osteoclasts. The ability of PPi to alter ATP release and NPP1/TNAP expression and activity indicates that cells can detect PPi levels and respond accordingly. Our data also raise the possibility that some actions of PPi on bone cells could be mediated by a Gαi-linked GPCR.


Assuntos
Difosfatos , Osteoclastos , Osteoclastos/metabolismo , Difosfatos/farmacologia , Toxina Pertussis/metabolismo , Toxina Pertussis/farmacologia , Osteoblastos/metabolismo , Colágeno/metabolismo , Trifosfato de Adenosina/metabolismo , Fosfatase Alcalina/metabolismo
17.
iScience ; 26(9): 107524, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37636067

RESUMO

Error-related potentials (ErrPs) are a prominent electroencephalogram (EEG) correlate of performance monitoring, and so crucial for learning and adapting our behavior. It is poorly understood whether ErrPs encode further information beyond error awareness. We report an experiment with sixteen participants over three sessions in which occasional visual rotations of varying magnitude occurred during a cursor reaching task. We designed a brain-computer interface (BCI) to detect ErrPs that provided real-time feedback. The individual ErrP-BCI decoders exhibited good transfer across sessions and scalability over the magnitude of errors. A non-linear relationship between the ErrP-BCI output and the magnitude of errors predicts individual perceptual thresholds to detect errors. We also reveal theta-gamma oscillatory coupling that co-varied with the magnitude of the required adjustment. Our findings open new avenues to probe and extend current theories of performance monitoring by incorporating continuous human interaction tasks and analysis of the ErrP complex rather than individual peaks.

18.
Heliyon ; 9(6): e17011, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37484216

RESUMO

Dolphins are marine mammals that often live in coastal habitats. Common causes of severe skeletal disorders among wild dolphins are congenital vertebral anomalities, collisions with sea vessels, trauma, hunting-related injury, infectious diseases, environmental pollution, and tumors. A free-ranging male, 3-year-old common dolphin (Delphinus delphis) was found dead in the coast of Asturias in northern Spain. Postmortem examination revealed lordosis in the caudal vertebral column, while X-ray imaging and computer tomography showed well-organized palisade-like periosteal proliferation, appearing as florid-like accretions, along the spinous apophysis of 26 lumbar-caudal vertebrae. The transverse apophysis was affected on only a few caudal vertebrae. The cortical layer remained intact. Histology of vertebra tissue showed periosteal proliferation of cancellous bone. The animal was diagnosed with hypertrophic osteopathy. The lungs showed diffuse parasitic granulomatous bronchointerstitial pneumonia caused by Halocercus delphini, consolidation of the pulmonary tissue, congestion, and alveolar edema. The animal was also afflicted by parasitic granulomatous gastritis caused by Anisakis simplex sensu lato and tattoo skin disease. The dolphin suffered from hypertrophic osteopathy associated with pulmonary Halocercus delphini infestation. This syndrome, known as hypertrophic pulmonary osteopathy, has been described in diverse terrestrial mammals, including domestic animals, wildlife and humans, but not in dolphins. This case reports the first description of hypertrophic osteopathy associated to a pulmonary disorder in dolphin, and it provides insights into factors that can induce column malformation in dolphins, suggesting the importance of taking thoracic lesions into account during differential diagnosis.

19.
Mov Disord Clin Pract ; 10(6): 992-997, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37332636

RESUMO

Background: Autosomal dominant spinocerebellar ataxia 36 (SCA36) is caused by hexanucleotide repeat expansion in the NOP56 gene. Objectives: To assess frequency, clinical and genetic features of SCA36 in Eastern Spain. Methods: NOP56 expansion was tested in a cohort of undiagnosed cerebellar ataxia families (n = 84). Clinical characterization and haplotype studies were performed. Results: SCA36 was identified in 37 individuals from 16 unrelated families. It represented 5.4% of hereditary ataxia patients. The majority were originally from the same region and displayed a shared haplotype. Mean age at onset was 52.5 years. Non-ataxic features included: hypoacusis (67.9%), pyramidal signs (46.4%), lingual fasciculations/atrophy (25%), dystonia (17.8%), and parkinsonism with evidence of dopaminergic denervation (10.7%). Conclusions: SCA36 is a frequent cause of hereditary ataxia in Eastern Spain, and is associated with a strong founder effect. SCA36 analysis should be considered prior to other studies, especially in AD presentations. Parkinsonism reported here broadens SCA36 clinical spectrum.

20.
PLoS One ; 18(5): e0282967, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37167243

RESUMO

The brain mechanism of embodiment in a virtual body has grown a scientific interest recently, with a particular focus on providing optimal virtual reality (VR) experiences. Disruptions from an embodied state to a less- or non-embodied state, denominated Breaks in Embodiment (BiE), are however rarely studied despite their importance for designing interactions in VR. Here we use electroencephalography (EEG) to monitor the brain's reaction to a BiE, and investigate how this reaction depends on previous embodiment conditions. The experimental protocol consisted of two sequential steps; an induction step where participants were either embodied or non-embodied in an avatar, and a monitoring step where, in some cases, participants saw the avatar's hand move while their hand remained still. Our results show the occurrence of error-related potentials linked to observation of the BiE event in the monitoring step. Importantly, this EEG signature shows amplified potentials following the non-embodied condition, which is indicative of an accumulation of errors across steps. These results provide neurophysiological indications on how progressive disruptions impact the expectation of embodiment for a virtual body.


Assuntos
Eletroencefalografia , Realidade Virtual , Humanos , Encéfalo , Mãos , Cabeça
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