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BACKGROUND: Adverse childhood experiences (ACEs) have been associated with volume alterations of stress-related brain structures among aging and clinical populations, however, existing studies have predominantly assessed only one type of ACE, with small sample sizes, and it is less clear if these associations exist among a general population of young adults. OBJECTIVE: The aims were to describe structural hippocampal volumetric differences by ACEs exposure and investigate the association between ACEs exposure and left and right hippocampal volume in a student sample of young adults. METHODS: 959 young adult students (18-24 years old) completed an online questionnaire on ACEs, mental health conditions, and sociodemographic characteristics. Magnetic resonance imaging (MRI) was used to measure left and right hippocampal volume (mm3). We used linear regression to explore the differences of hippocampal volumes in university students with and without ACEs. RESULTS: Two thirds of students (65.9%) reported ACEs exposure. As ACEs exposure increased there were significant volumetric reductions in left (p < 0.0001) and right hippocampal volume (p = 0.001) and left (p = 0.0023) and right (p = 0.0013) amygdala volume. After adjusting for intracranial brain volume, sex, age, and depression diagnosis there was a negative association between ACEs exposure and left (ß = -22.6, CI = -44.5, -0.7, p = 0.0412) but not right hippocampal volume (ß = -18.3, CI = -39.2, 2.6, p = 0.0792). After adjusting for intracranial volume there were no associations between ACEs exposure and left (ß = -9.2, CI = -26.2, 7.9 p = 0.2926) or right (ß = -5.6, CI = -19.9,8.8 p = 0.4466) amygdala volume. CONCLUSIONS: Hippocampal volume varied by ACEs exposure in young adult students. ACEs appear to contribute to neuroanatomic differences in young adults from the general population.
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Eplet 52SK is unique in the HLA eplet registry as targeting the whole family of DQA1*01 alleles. It is proposed as an antibody-verified eplet but has not been validated enough to deserve this label. Especially, confusion can occur with reactivity targeting the 52PQ eplet which is present on the DQB1*05 and DQB1*06 alleles families, as DQ molecule stability imposes DQA1*01 to selectively associate with these DQ-ß families only. Using two Luminex single antigen (LSA) assays from two vendors, beads bearing DR-α/DQ6 heterodimers, a special build LSA panel of additional DQ beads, and an adsorption/elution strategy relying on cells from deceased donors or recombinant cells solely expressing one DQ antigen, we definitely established the antibody-verified status of eplet 52SK using patients' sera reacting only against the DQ5 and DQ6 beads of the One Lambda LSA panel in routine patients' follow up. We also show that reactivity against this eplet is not a rare event among anti-DQ1 immunisation. This study further strengthens the importance of considering the DQA1 locus in immunological studies of HLA and in organ allocation strategies.
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Alelos , Cadeias alfa de HLA-DQ , Teste de Histocompatibilidade , Humanos , Cadeias alfa de HLA-DQ/genética , Cadeias alfa de HLA-DQ/imunologia , Teste de Histocompatibilidade/métodos , Isoanticorpos/imunologia , Antígenos HLA-DQ/genética , Antígenos HLA-DQ/imunologiaRESUMO
INTRODUCTION: Wild-type transthyretin amyloidosis (ATTRwt) is a rare but serious disease that is underestimated due to asymptomatic progression. Cardiac deposits worsen prognosis, highlighting the importance of early detection for preventive treatment. CASE REPORT: An elderly patient presented with an osteolytic lesion of the middle ear. Pathology diagnosed amyloid transthyretin deposits associated with cholesteatoma. DISCUSSION: Identifying reliable markers to screen for risk of cardiac amyloidosis is important, due to poor prognosis. Recent studies found higher prevalence of hearing loss in ATTRwt than in the general population. The present case identified the middle ear as a target of ATTR, which could improve our understanding of the pathophysiology.
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BACKGROUND: Spasticity is a common and potentially debilitating symptom of multiple sclerosis (MS) with a highly variable presentation. Understanding, quantifying, and managing MS-associated spasticity (MSS) is a challenge for research and in clinical practice. The tetrahydrocannabinol:cannabidiol oromucosal spray nabiximols has demonstrated beneficial effects in the treatment of MSS in clinical studies as well as real-world observational studies, and is approved for the treatment of MSS in 29 countries globally. Most randomized studies evaluated the efficacy of nabiximols using the change in average daily spasticity scores reported by patients using the spasticity Numeric Rating Scale as a primary endpoint. This study, RELEASE MSS1 (NCT04657666), was conducted using a prespecified primary endpoint of change in spastic muscle tone (Modified Ashworth Scale Lower Limb Muscle Tone-6 [MAS LLMT-6]) to corroborate the efficacy of nabiximols as adjunctive therapy observed with the patient-measured spasticity Numeric Rating Scale primary endpoint in the previous pivotal studies. METHODS: This was a phase 3, multicenter, randomized, double-blind, placebo-controlled, 2-treatment, 2-period, crossover trial. Because of the prevalence and functional impact of lower limb spasticity on the individual patient's overall experience of MS spasticity, the MAS LLMT-6 was derived from the clinician-rated MAS. The MAS LLMT-6 is the average transformed MAS score of 6 muscle groups (knee flexors, knee extensors, and ankle plantar flexors; all assessed bilaterally). Secondary measures included MAS LLMT-4 scores, defined as the average of the 4 individual MAS-transformed scores of knee flexors and knee extensors bilaterally. Patients had a diagnosis of MS and an untransformed MAS score of at least 2 in ≥2 of 6 LLMT-6 muscle groups despite current treatment with ≥1 of the following oral antispasticity agents: baclofen, tizanidine, or dantrolene. Eligible participants were randomly assigned to 1 of 2 treatment sequences. Each treatment sequence consisted of two treatment periods, each consisting of a 14-day dose titration phase followed by a 7-day dose maintenance phase. RESULTS: Of 68 patients enrolled, 33 were assigned to nabiximols followed by placebo and 35 were assigned to placebo followed by nabiximols. Least squares mean changes in MAS LLMT-6 scores from baseline to day 21 were -0.23 for nabiximols and -0.26 for placebo; the least squares mean treatment difference in MAS LLMT-6 scores for nabiximols versus placebo was 0.04, which was not statistically significant (P = 0.7152). Mean changes in MAS LLMT-4 scores from baseline to day 21 also were not significantly different between the nabiximols and placebo groups. Safety results in this study were consistent with the known safety profile of nabiximols in patients with MSS. CONCLUSION: Despite the established efficacy of nabiximols in MSS observed using patient-reported measures, the primary endpoint was not met in this study. The findings from this study reflect and emphasize some of the challenges in the evaluation and treatment of MS spasticity. CLINICAL TRIAL REGISTRATION NUMBER (CLINICALTRIALS.GOV): : NCT04657666.
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Canabidiol , Dronabinol , Combinação de Medicamentos , Esclerose Múltipla , Espasticidade Muscular , Humanos , Espasticidade Muscular/tratamento farmacológico , Espasticidade Muscular/etiologia , Canabidiol/administração & dosagem , Canabidiol/farmacologia , Dronabinol/administração & dosagem , Dronabinol/farmacologia , Método Duplo-Cego , Esclerose Múltipla/complicações , Esclerose Múltipla/tratamento farmacológico , Adulto , Masculino , Sprays Orais , Feminino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de SaúdeRESUMO
BACKGROUND: In the treatment of oral cavity cancer, margin status is one of the most critical prognostic factors. Positive margins are associated with higher local recurrence and lower survival rates. Therefore, the universal goal of oral surgical oncology is to achieve microscopically clear margins. Near-infrared fluorescence guided surgery (FGS) could improve surgical resection using fluorescent probes. αVß6 integrin has shown great potential for cancer targeting due to its overexpression in oral cancers. Red fluorescent contrast agent IRDye 680 coupled with anti-αVß6 peptide (IRDye-A20) represents an asset to improve FGS of oral cancer. This study investigates the potential of IRDye-A20 as a selective imaging agent in 3D three-dimensional tongue cancer cells. METHODS: αVß6 integrin expression was evaluated by RT-qPCR and Western Blotting in 2D HSC-3 human tongue cancer cells and MRC-5 human fibroblasts. Targeting ability of IRDye-A20 was studied in both cell lines by flow cytometry technique. 3D tumor spheroid models, homotypic (HSC-3) and stroma-enriched heterotypic (HSC-3/MRC-5) spheroids were produced by liquid overlay procedure and further characterized using (immuno)histological and fluorescence-based techniques. IRDye-A20 selectivity was evaluated in each type of spheroids and each cell population. RESULTS: αVß6 integrin was overexpressed in 2D HSC-3 cancer cells but not in MRC-5 fibroblasts and consistently, only HSC-3 were labelled with IRDye-A20. Round shaped spheroids with an average diameter of 400 µm were produced with a final ratio of 55%/45% between HSC-3 and MRC-5 cells, respectively. Immunofluorescence experiments demonstrated an uniform expression of αVß6 integrin in homotypic spheroid, while its expression was restricted to cancer cells only in heterotypic spheroid. In stroma-enriched 3D model, Cytokeratin 19 and E-cadherin were expressed only by cancer cells while vimentin and fibronectin were expressed by fibroblasts. Using flow cytometry, we demonstrated that IRDye-A20 labeled the whole homotypic spheroid, while in the heterotypic model all cancer cells were highly fluorescent, with a negligible fluorescence in fibroblasts. CONCLUSIONS: The present study demonstrated an efficient selective targeting of A20FMDV2-conjugated IRDye 680 in 3D tongue cancer cells stroma-enriched spheroids. Thus, IRDye-A20 could be a promising candidate for the future development of the fluorescence-guided surgery of oral cancers.
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Performing molecular dynamics simulations with the TIP4P/2005 water model along 9 isobars (from 175 to 375 bar) in the temperature range between 300 and 1100 K, we have found that the loci of the extrema in the rate of change of specific structural properties can be used to define purely structure-based Widom lines. We have examined several parameters that describe the local structure of water, such as the tetrahedral arrangement, nearest neighbor distance, local density around the molecules, and the size of the largest dense domain. The last two parameters were determined using the Voronoi polyhedral and density-based spatial clustering of applications with noise methods, respectively. By analyzing the moments of the associated distributions, we show that along a given isobar, the temperature at which we observe a maximum in the fluctuation, the rate of change of the average values, or in the skewness values unambiguously determines the Widom line that is in agreement with the experimentally detected, thermodynamic response function-based ones.
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In transplantation, anti-HLA Abs, especially targeting the DQ locus, are well-known to lead to rejection. These Abs identified by Luminex single Ag assays recognize polymorphic amino acids on HLA, named eplets. The HLA Eplet Registry included 83 DQ eplets, mainly deduced from amino acid sequence alignments, among which 66 have not been experimentally verified. Because eplet mismatch load may improve organ allocation and transplant outcomes, it is imperative to confirm the genuine reactivity of eplets to validate this approach. Our study aimed to confirm 29 nonverified eplets, using adsorption of eplet-positive patients' sera on human spleen mononuclear cells and on transfected murine cell clones expressing a unique DQα- and DQß-chain combination. In addition, we compared the positive beads patterns obtained in the two commercially available Luminex single Ag assays. Among the 29 nonverified DQ eplets studied, 24 were confirmed by this strategy, including the 7 DQα eplets 40E, 40ERV, 75I, 76 V, 129H, 129QS, and 130A and the 17 DQß eplets 3P, 23L, 45G, 56L, 57 V, 66DR, 66ER, 67VG, 70GT, 74EL, 86A, 87F, 125G, 130R, 135D, 167R, and 185I. However, adsorption results did not allow us to conclude for the five eplets 66IT, 75S, 160D, 175E, and 185T.
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Antígenos HLA-DQ , Humanos , Animais , Camundongos , Antígenos HLA-DQ/imunologia , Teste de Histocompatibilidade/métodos , Rejeição de Enxerto/imunologia , Leucócitos Mononucleares/imunologia , Sequência de AminoácidosRESUMO
Senescent cells are blocked in the cell cycle but remain metabolically active. These cells, once engaged in the senescence process, fail to initiate DNA replication. Due to the shortening of telomeres, replicative senescence can be triggered by a DNA damage response. Moreover, cells can also be induced to senesce by DNA damage in response to elevated reactive oxygen species (ROS), activation of oncogenes, cell-cell fusion or after ionizing radiation. There are multiple experimental ways to detect senescent cells directly or indirectly. Senescence-associated cellular traits (SA ß-Gal activity, increase in cell volume and lysosome content, appearance of γ-H2AX foci, increase of ROS and oxidative damage adducts, etc.) can be identified by numerous methods of detection (flow cytometry, confocal imaging, in situ staining, etc.). Here, we improved an existing flow cytometry protocol and further developed a new one specifically tailored to ionizing radiation-induced endothelial senescence. Thus, we have upgraded the Debacq-Chainiaux protocol and added improvements in this protocol (i) to better detect positive events (ii) to offer a compatibility to simultaneously analyze various intracellular molecules including phosphorylated signaling proteins and cytokines, whether related or not to senescence processes.
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Senescência Celular , Espécies Reativas de Oxigênio/metabolismo , Senescência Celular/genética , Células Cultivadas , FenótipoRESUMO
Background: An MRI is potentially hazardous for patients with retained ferromagnetic bullets. Recent studies have aimed to develop dual-energy computed tomography (DECT) as a screening tool for recognising highly ferromagnetic bullets. Inconsistent findings have been ascribed to inherent CT technology differences. Previous research demonstrated significant Hounsfield unit (HU) measurement variation among single-source CT machines. Objectives: This study investigated the theoretical dual-energy index (DEI) variation between DECT machines when evaluating the potential ferromagnetic properties within the same sample of ex vivo bullets and metal phantoms. Method: An experimental ex vivo study was conducted on eight metal phantoms and 10 unused bullets individually positioned in the same Perspex head phantom and scanned on two DECT machines. Two senior radiology registrars independently recorded the HU readings, and DEI values were calculated. Statistical analysis was performed using non-parametric methods for paired data, namely the Signed Rank Test. The DEI values based on mean HU readings between the DECT machines were compared. Results: Inter- and intra-reader agreement was not statistically significant. The metal phantoms had poor interscanner agreement, with an overlap of the ferromagnetic and non-ferromagnetic ranges. The bullets had good interscanner agreement, with a similar ferromagnetic to non-ferromagnetic relationship. Conclusion: The use of DEI values negates the previous assumption that significant interscanner variability exists among different DECT technologies while assessing highly attenuative ex vivo bullets. Contribution: This investigation demonstrated that even though HU readings may be variable, the implementation of the DEI equation translates this into comparable values with good interscanner agreement.
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Rhythms are a common feature of brain activity. Across different types of rhythms, the phase has been proposed to have functional consequences, thus requiring its accurate specification from noisy data. Phase is conventionally specified using techniques that presume a frequency band-limited rhythm. However, in practice, observed brain rhythms are typically nonsinusoidal and amplitude modulated. How these features impact methods to estimate phase remains unclear. To address this, we consider three phase estimation methods, each with different underlying assumptions about the rhythm. We apply these methods to rhythms simulated with different generative mechanisms and demonstrate inconsistency in phase estimates across the different methods. We propose two improvements to the practice of phase estimation: (1) estimating confidence in the phase estimate, and (2) examining the consistency of phase estimates between two (or more) methods.
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Encéfalo , Eletroencefalografia , Incerteza , Eletroencefalografia/métodosRESUMO
In a cross sectional study of 13,837 university students, we aimed to explore the association between attention deficit hyperactivity disorder (ADHD) symptoms and lifetime psychoactive substance use (LPSU) on a wide range of illicit substances. Logistic and Hurdel multivariable regressions were used. ADHD symptoms were significantly associated with the lifetime use of ketamine, magic mushrooms, poppers, and nine other psychoactive substances. There was an association between ADHD symptoms and both LPSU and truncated count of lifetime psychoactive substance use. High levels of ADHD symptoms are associated with the use of a large variety and multiple LPSU.
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Rhythms are a common feature of brain activity. Across different types of rhythms, the phase has been proposed to have functional consequences, thus requiring its accurate specification from noisy data. Phase is conventionally specified using techniques that presume a frequency band-limited rhythm. However, in practice, observed brain rhythms are typically non-sinusoidal and amplitude modulated. How these features impact methods to estimate phase remains unclear. To address this, we consider three phase estimation methods, each with different underlying assumptions about the rhythm. We apply these methods to rhythms simulated with different generative mechanisms and demonstrate inconsistency in phase estimates across the different methods. We propose two improvements to the practice of phase estimation: (1) estimating confidence in the phase estimate, and (2) examining the consistency of phase estimates between two (or more) methods.
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Radiation-induced toxicity of the digestive tract is a major clinical concern as many cancer survivors have received radiotherapy for tumours of the abdominopelvic area. The coordination and orchestration of a tissue's response to stress depend not only on the phenotype of the cells that make up the tissue but also on cell-cell interactions. The digestive system, i.e., the intestine/colon/rectum, is made up of a range of different cell populations: epithelial cells, stromal cells, i.e. endothelial cells and mesenchymal lineages, immune cells and nerve cells. Moreover, each of these populations is heterogeneous and presents very significant plasticity and differentiation states. The pathogenesis of radiation-induced digestive lesions is an integrated process that involves multiple cellular compartments interacting in a complex sequence of events. Understanding all the cellular events and communication networks that contribute to the tissue's response to stress is therefore a major conceptual and methodological scientific challenge. The study of heterogeneous populations of cells in a tissue is now possible thanks to "single cell' RNA sequencing and spatial transcriptomics techniques, which enable a comprehensive study of the transcriptomic profiles of individual cells in an integrated system. In addition, the mathematical and bioinformatics tools that are now available for the large-scale analysis of data allow the inference of cell-cell communication networks. Such approaches have become possible through advances in bioinformatics algorithms for the analysis and deciphering of interaction networks. Interactions influence the tissue regeneration process through expression of various molecules, including metabolites, integrins, junction proteins, ligands, receptors and proteins secreted into the extracellular space. The vascular network is viewed as a key player in the progression of digestive lesions, which are characterised by infiltration of a range of immune cells. A better characterisation of endothelium/immune cell interactions in suitable preclinical models, as well as in humans, may help to identify some promising therapeutic targets for the prediction, prevention or treatment of digestive toxicity after radiotherapy.
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Neoplasias , Lesões por Radiação , Humanos , Células Endoteliais , Endotélio Vascular/patologia , Neoplasias/patologia , Lesões por Radiação/patologia , FenótipoRESUMO
PURPOSE: Although attention deficit hyperactivity disorder (ADHD) has been associated with illicit stimulants use, less is known about their prospective association in university students. We aimed to examine the association between ADHD symptoms at inclusion and illicit stimulants use following 1 year among university students. METHODS: The i-Share cohort recruited French students from February 2013 to July 2020. The study included 4270 participants. The Adult ADHD Self-Report Scale (ASRS) was used to evaluate ADHD symptoms at inclusion. Illicit stimulants use was assessed at inclusion and 1 year after inclusion. Multivariable logistic regressions were conducted to assess the association between ADHD symptoms at inclusion and illicit stimulants use following 1 year. RESULTS: High levels of ADHD symptoms at inclusion were associated with a greater probability of illicit stimulants use following 1 year (adjusted OR: 2.42 (1.51-3.8)). The adjusted odds ratio was 2.7 (1.08-7.84) among participants who had used illicit stimulant at least once (continuation) and 2.25 (1.04-4.37) among participants who had never used illicit stimulants at inclusion (initiation). CONCLUSION: High levels of ADHD symptoms are a feature that may promote both initiation and continuation of illicit stimulants use among university students. Our findings suggest that university students with high levels of ADHD symptoms may benefit from screening to help identify those at risk of illicit stimulants use.
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Patients with deep and extensive wounds need urgent skin coverage to re-establish the cutaneous barrier that prevents life-threatening infections and dehydration. However, the current clinically-available skin substitutes intended for permanent coverage are limited in number, and a trade-off between production time and quality must be made. Here, we report the use of decellularized self-assembled dermal matrices to reduce by half the manufacturing process time of clinical-grade skin substitutes. These decellularized matrices can be stored for over 18 months and recellularized with patients' cells in order to generate skin substitutes that show outstanding histological and mechanical properties in vitro. Once grafted in mice, these substitutes persist over weeks with high graft take, few contraction events, and high stem cell content. These next-generation skin substitutes constitute a substantial advancement in the treatment of major burn patients, combining, for the first time, high functionality, rapid manufacturability and easy handling for surgeons and healthcare practitioners. Future clinical trials will be conducted to assess the advantages of these substitutes over existing treatments. STATEMENT OF SIGNIFICANCE: The number of patients in need for organ transplantation is ever-growing and there is a shortage in tissue and organ donors. In this study, we show for the first time that we can preserve decellularized self-assembled tissues and keep them in storage. Then, in only three weeks we can use them to produce bilayered skin substitutes that have properties very close to those of the native human skin. These findings therefore represent a major step forward in the field of tissue engineering and organ transplantation, paving the way toward a universal off-the-shelf biomaterial for tissue reconstruction and surgery that will be beneficial for many clinicians and patients.
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Pele Artificial , Humanos , Camundongos , Animais , Engenharia Tecidual , Pele/patologia , Transplante de Pele , Materiais BiocompatíveisRESUMO
Introduction: A highly efficacious and durable vaccine against malaria is an essential tool for global malaria eradication. One of the promising strategies to develop such a vaccine is to induce robust CD8+ T cell mediated immunity against malaria liver-stage parasites. Methods: Here we describe a novel malaria vaccine platform based on a secreted form of the heat shock protein, gp96-immunoglobulin, (gp96-Ig) to induce malaria antigen specific, memory CD8+ T cells. Gp96-Ig acts as an adjuvant to activate antigen presenting cells (APCs) and chaperone peptides/antigens to APCs for cross presentation to CD8+ T cells. Results: Our study shows that vaccination of mice and rhesus monkeys with HEK-293 cells transfected with gp96-Ig and two well-known Plasmodium falciparum CSP and AMA1 (PfCA) vaccine candidate antigens, induces liver-infiltrating, antigen specific, memory CD8+ T cell responses. The majority of the intrahepatic CSP and AMA1 specific CD8+ T cells expressed CD69 and CXCR3, the hallmark of tissue resident memory T cells (Trm). Also, we found intrahepatic, antigen-specific memory CD8+ T cells secreting IL-2, which is relevant for maintenance of effective memory responses in the liver. Discussion: Our novel gp96-Ig malaria vaccine strategy represents a unique approach to induce liver-homing, antigen-specific CD8+ T cells critical for Plasmodium liver-stage protection.
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Vacinas Antimaláricas , Malária Falciparum , Malária , Humanos , Proteínas de Choque Térmico/metabolismo , Células HEK293 , Linfócitos T CD8-Positivos , Imunoglobulinas/metabolismo , Antígenos de Protozoários , Malária/prevenção & controle , Malária/metabolismoRESUMO
The nutritional value, heavy metal content and lipid quality of five marine fishes from, Cameroon coast were be investigated. Fish samples from Ilisha africana, Sardinella, maderensis, Cyprinus carpio, Arius parkii and Ethmalosa fimbriata were collected at, the Douala sea port, carried to the laboratory, washed with distilled water and, processed. Proximal composition, minerals, lipid quality and heavy metal analyses, were performed using AOAC standard methods. Results show that proteins (18.43%), and lipids (3.69%) contents were higher in Ilisha africana. Cyprinus carpio had the, highest ash content (4.59%). Contents of minerals and heavy metals were found as, follows: P > Mg > K > Ca > Na > Fe > Zn > Cu > Mn and Hg > Pb > Cd > As. Oils extracted from C. carpio, A. parkii and E. fimbriata were semi-siccative while those of I. africana and S. maderensis were siccative. Thus, these fish species are good sources of proteins and, minerals that can be used for managing mineral deficiencies in humans and animals.
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The long-term success of intraosseous transcutaneous amputation prostheses (ITAPs) mainly relies on dermal attachment of skin cells to the implant. Otherwise, bacteria can easily penetrate through the interface between the implant and the skin. Therefore, infection at this implant/skin interface remains a significant complication in orthopedic surgeries in which these prostheses are required. Two main strategies were investigated to prevent these potential infection problems which consist in either establishing a strong sealing at the skin/implant interface or on eradicating infections by killing bacteria. In this work, two adhesion peptides, either KRGDS or KYIGSR and one antimicrobial peptide, Magainin 2 (Mag 2), were covalently grafted via phosphonate anchor arms to the surface of the Ti6Al4V ELI (extra low interstitials) material, commonly used to manufacture ITAPs. X-ray photoelectron spectroscopy, contact angle, and confocal microscopy analyses enabled to validate the covalent and stable grafting of these three peptides. Dermal fibroblasts cultures on bare Ti6Al4V ELI surfaces and functionalized ones displayed a good cell adhesion and proliferation on all samples. However, cell spreading and viability appeared to be improved on grafted surfaces, especially for those conjugated with KRGDS and Mag 2. Moreover, the dermal sheet attachment, was significantly higher on surfaces functionalized with Mag 2 as compared to the other surfaces. Therefore, the surface functionalization with the antimicrobial peptide Mag 2 seems to be the best approach for the targeted application, as it could play a dual role, inducing a strong skin adhesion while limiting infections on Ti6Al4V ELI materials.
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Próteses e Implantes , Titânio , Titânio/química , Adesão Celular , Peptídeos , Amputação Cirúrgica , Peptídeos Antimicrobianos , Propriedades de SuperfícieRESUMO
Temporal-lobe epilepsy in humans is often associated with widespread, synchronized neuron firing that co-occurs with traveling waves in local field potential. These traveling waves generate stochastic oscillations in a time series of microelectrode voltage, and previous work has deemed it informative for traveling-wave analysis to study the mean periodicity. This manuscript reveals that: a) mean voltage (i.e., traveling-wave periodicity) adequately explains the observed voltage periodicity only for a select few time intervals during seizure; and b) mean voltage has a 7 Hz cosine-series representation indicative of a nonlinear system response given alpha-rhythm input. The a) result implies that residual noise should be modelled explicitly, while b) motivates a departure from the conventional plane-wave modeling regime in source-localization efforts. The 7 Hz fundamental frequency is unsurprising given the relative transparency of the brain to 14 Hz alpha rhythms in neurophysiological diseases (14 Hz being a subharmonic frequency of the 7 Hz signal).
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The self-assembled skin substitute (SASS) is an autologous bilayered skin substitute designed by our academic laboratory, the Laboratoire d'Organogenèse Expérimentale (LOEX) to offer definitive treatment for patients lacking donor sites (unwounded skin) to cover their burn wounds. This product shows skin-like attributes, such as an autologous dermal and epidermal layer, and is easily manipulable by the surgeon. Its development stems from the need for skin replacement in high total body surface area burned survivors presenting few donor sites for standard split-thickness skin grafting. This review aims to present the history, successes, challenges, and current therapeutic indications of this skin substitute. We review the product's development history, before discussing current production techniques, as well as clinical use. The progression observed since the initial SASS production technique described in 1999, up to the most recent technique expresses significant advances made in the technical aspect of our product, such as the reduction of the production time. We then explore the efficacy and benefits of SASS over existing skin substitutes and discuss the outcomes of a recent study focusing on the successful treatment of 14 patients. Moreover, an ongoing cross-Canada study is further assessing the product's safety and efficacy. The limitations and technical challenges of SASS are also discussed.