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Non-volatile magnetic random-access memories (MRAMs), such as spin-transfer torque MRAM and next-generation spin-orbit torque MRAM, are emerging as key to enabling low-power technologies, which are expected to spread over large markets from embedded memories to the Internet of Things. Concurrently, the development and performances of devices based on two-dimensional van der Waals heterostructures bring ultracompact multilayer compounds with unprecedented material-engineering capabilities. Here we provide an overview of the current developments and challenges in regard to MRAM, and then outline the opportunities that can arise by incorporating two-dimensional material technologies. We highlight the fundamental properties of atomically smooth interfaces, the reduced material intermixing, the crystal symmetries and the proximity effects as the key drivers for possible disruptive improvements for MRAM at advanced technology nodes.
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Alphaviruses encode an error-prone RNA-dependent RNA polymerase (RdRp), nsP4, required for genome synthesis, yet how the RdRp functions in the complete alphavirus life cycle is not well-defined. Previous work using chikungunya virus has established the importance of the nsP4 residue cysteine 483 in replication. Given the location of residue C483 in the nsP4 palm domain, we hypothesized that other residues within this domain and surrounding subdomains would also contribute to polymerase function. To test this hypothesis, we designed a panel of nsP4 variants via homology modeling based on the coxsackievirus B3 3D polymerase. We rescued each variant in mammalian and mosquito cells and discovered that the palm domain and ring finger subdomain contribute to host-specific replication. In C6/36 cells, we found that while the nsP4 variants had replicase function similar to that of wild-type CHIKV, many variants presented changes in protein accumulation and virion production even when viral nonstructural and structural proteins were produced. Finally, we found that WT CHIKV and nsP4 variant replication and protein production could be enhanced in mammalian cells at 28°C, yet growing virus under these conditions led to changes in virus infectivity. Taken together, these studies highlight that distinct nsP4 subdomains are required for proper RNA transcription and translation, having major effects on virion production.
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Virus Chikungunya , ARN Polimerasa Dependiente del ARN , Virión , Replicación Viral , Virus Chikungunya/genética , Virus Chikungunya/metabolismo , Replicación Viral/fisiología , Animales , ARN Polimerasa Dependiente del ARN/metabolismo , ARN Polimerasa Dependiente del ARN/genética , Virión/metabolismo , Fiebre Chikungunya/virología , Fiebre Chikungunya/metabolismo , Humanos , Proteínas Virales/metabolismo , Proteínas Virales/genética , Proteínas no Estructurales Virales/metabolismo , Proteínas no Estructurales Virales/genética , Línea Celular , Dominios ProteicosRESUMEN
Burkitt lymphoma (BL) accounts for most pediatric non-Hodgkin lymphomas, being less common but significantly more lethal when diagnosed in adults. Much of the knowledge of the genetics of BL thus far has originated from the study of pediatric BL (pBL), leaving its relationship to adult BL (aBL) and other adult lymphomas not fully explored. We sought to more thoroughly identify the somatic changes that underlie lymphomagenesis in aBL and any molecular features that associate with clinical disparities within and between pBL and aBL. Through comprehensive whole-genome sequencing of 230 BL and 295 diffuse large B-cell lymphoma (DLBCL) tumors, we identified additional significantly mutated genes, including more genetic features that associate with tumor Epstein-Barr virus status, and unraveled new distinct subgroupings within BL and DLBCL with 3 predominantly comprising BLs: DGG-BL (DDX3X, GNA13, and GNAI2), IC-BL (ID3 and CCND3), and Q53-BL (quiet TP53). Each BL subgroup is characterized by combinations of common driver and noncoding mutations caused by aberrant somatic hypermutation. The largest subgroups of BL cases, IC-BL and DGG-BL, are further characterized by distinct biological and gene expression differences. IC-BL and DGG-BL and their prototypical genetic features (ID3 and TP53) had significant associations with patient outcomes that were different among aBL and pBL cohorts. These findings highlight shared pathogenesis between aBL and pBL, and establish genetic subtypes within BL that serve to delineate tumors with distinct molecular features, providing a new framework for epidemiologic, diagnostic, and therapeutic strategies.
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Linfoma de Burkitt , Infecciones por Virus de Epstein-Barr , Linfoma de Células B Grandes Difuso , Niño , Humanos , Adulto , Linfoma de Burkitt/patología , Herpesvirus Humano 4 , Linfoma de Células B Grandes Difuso/patología , MutaciónRESUMEN
BACKGROUND: Plant diseases are driven by an intricate set of defense mechanisms counterbalanced by the expression of host susceptibility factors promoted through the action of pathogen effectors. In spite of their central role in the establishment of the pathology, the primary components of plant susceptibility are still poorly understood and challenging to trace especially in plant-fungal interactions such as in Fusarium head blight (FHB) of bread wheat. Designing a system-level transcriptomics approach, we leveraged the analysis of wheat responses from a susceptible cultivar facing Fusarium graminearum strains of different aggressiveness and examined their constancy in four other wheat cultivars also developing FHB. RESULTS: In this study, we describe unexpected differential expression of a conserved set of transcription factors and an original subset of master regulators were evidenced using a regulation network approach. The dual-integration with the expression data of pathogen effector genes combined with database mining, demonstrated robust connections with the plant molecular regulators and identified relevant candidate genes involved in plant susceptibility, mostly able to suppress plant defense mechanisms. Furthermore, taking advantage of wheat cultivars of contrasting susceptibility levels, a refined list of 142 conserved susceptibility gene candidates was proposed to be necessary host's determinants for the establishment of a compatible interaction. CONCLUSIONS: Our findings emphasized major FHB determinants potentially controlling a set of conserved responses associated with susceptibility in bread wheat. They provide new clues for improving FHB control in wheat and also could conceivably leverage further original researches dealing with a broader spectrum of plant pathogens.
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Fusarium , Triticum , Triticum/genética , Redes Reguladoras de Genes , AgresiónRESUMEN
The resistance of gram-negative bacteria to silver ions is mediated by a silver efflux pump, which mainly relies on a tripartite efflux complex SilCBA, a metallochaperone SilF and an intrinsically disordered protein SilE. However, the precise mechanism by which silver ions are extruded from the cell and the different roles of SilB, SilF, and SilE remain poorly understood. To address these questions, we employed nuclear magnetic resonance and mass spectrometry to investigate the interplay between these proteins. We first solved the solution structures of SilF in its free and Ag+-bound forms, and we demonstrated that SilB exhibits two silver binding sites in its N and C termini. Conversely to the homologous Cus system, we determined that SilF and SilB interact without the presence of silver ions and that the rate of silver dissociation is eight times faster when SilF is bound to SilB, indicating the formation of a SilF-Ag-SilB intermediate complex. Finally, we have shown that SilE does not bind to either SilF or SilB, regardless of the presence or absence of silver ions, further corroborating that it merely acts as a regulator that prevents the cell from being overloaded with silver. Collectively, we have provided further insights into protein interactions within the sil system that contribute to bacterial resistance to silver ions.
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Plata , Transporte Biológico , Iones/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Plata/metabolismoRESUMEN
Leg Ulcer (LU) pathophysiology is still not well understood in sickle cell anaemia (SCA). We hypothesised that SCA patients with LU would be characterised by lower microvascular reactivity. The aim of the present study was to compare the microcirculatory function (transcutaneous oxygen pressure (TcPO2) on the foot and laser Doppler flowmetry on the arm) and several blood biological parameters between nine SCA patients with active LU (LU+) and 56 SCA patients with no positive history of LU (LU-). We also tested the effects of plasma from LU+ and LU- patients on endothelial cell activation. We observed a reduction of the TcPO2 in LU+ compared to LU- patients. In addition, LU+ patients exhibited lower cutaneous microvascular vasodilatory capacity in response to acetylcholine, current and local heating compared to LU- patients. Inflammation and endothelial cell activation in response to plasma did not differ between the two groups. Among the nine patients from the LU+ group, eight were followed and six achieved healing in 4.4 ± 2.5 months. Among thus achieving healing, microvascular vasodilatory capacity in response to acetylcholine, current and local heating and TcPO2 improved after healing. In conclusion, microcirculatory function is impaired in patients with LU, and improves with healing.
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BACKGROUND: Aging, characterized by a slow and progressive alteration of cognitive functions, is associated with gut microbiota dysbiosis, low-grade chronic inflammation, as well as increased oxidative stress and neurofunctional alterations. Some nutrients, such as polyphenols, carotenoids, and omega (ω)-3 (n-3), are good candidates to prevent age-related cognitive decline, because of their immunomodulatory, antioxidant, and neuroprotective properties. OBJECTIVES: The objective of this study was to demonstrate the preventive effect of a combination of plant extracts (PE) containing Memophenol™ (grapes and blueberries polyphenols) and a patented saffron extract (saffron carotenoids and safranal) and ω-3 on cognitive function in a mouse model of accelerated aging and to understand the biological mechanisms involved. METHODS: We used an accelerated-aging model by injecting 3-mo-old male C57Bl6/J mice with D-galactose for 8 wk, during which they were fed with a balanced control diet and supplemented or not with PE and/or ω-3 (n = 15-16/group). Short-term memory was evaluated by Y-maze test, following analyses of hippocampal and intestinal RNA expressions, brain fatty acid and oxylipin amounts, and gut microbiota composition (16S rRNA gene sequencing). Statistical analyses were performed (t test, analysis of variance, and Pearson correlation). RESULTS: Our results showed that oral administration of PE, ω-3, or both (mix) prevented hippocampus-dependent short-term memory deficits induced by D-galactose (P < 0.05). This effect was accompanied by the modulation of gut microbiota, altered by the treatment. PE and the mix increased the expression of antioxidative and neurogenesis markers, such as catalase and doublecortin, in hippocampus (P < 0.05 for both). Moreover, ω-3 and the mix showed a higher ω-3 amounts (P < 0.05) and EPA-derived 18- hydroxyeicosapentaenoic acid (P < 0.001) in prefrontal cortex. These changes may contribute to the improvement in memory. CONCLUSIONS: These results suggest that the mix of PE and ω-3 could be more efficient at attenuating age-related cognitive decline than individual supplementations because it targeted, in mice, the different pathways impaired with aging.
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OBJECTIVE AND DESIGN: Neuroinflammation is a protective mechanism but can become harmful if chronic and/or unregulated, leading to neuronal damage and cognitive alterations. Limiting inflammation and promoting resolution could be achieved with nutrients such as grapes and blueberries polyphenols, saffron carotenoids, and omega-3, which have anti-inflammatory and proresolutive properties. METHODS: This study explored the impact of 18-day supplementation with plant extracts (grape, blueberry and saffron), omega-3 or both (mix) on neuroinflammation induced by lipopolysaccharide (LPS, 250 µg/kg) in 149 mice at different time points post-LPS treatment (30 min, 2 h, 6 h). Inflammatory, oxidative and neuroprotective gene expression; oxylipin quantification; and fatty acid composition were analyzed at each time point. PCA analysis was performed with all these biomarkers. RESULTS: Mix supplementation induced changes in the resolution of inflammation. In fact, the production of proinflammatory mediators in the hippocampus started earlier in the supplemented group than in the LPS group. Pro-resolving mediators were also found in higher quantities in supplemented mice. These changes were associated with increased hippocampal antioxidant status at 6 h post-LPS. CONCLUSIONS: These findings suggest that such dietary interventions with plant extracts, and omega-3 could be beneficial in preventing neuroinflammation and, consequently, age-related cognitive decline. Further research is needed to explore the effects of these supplements on chronic inflammation in the context of aging.
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BACKGROUND: Evidence is needed to understand factors that influence child development and caregiving experiences, especially in marginalized contexts, to inform the development and implementation of early childhood development (ECD) interventions. This study explores caregiving practices for young children in an urban informal settlement with Kenyans and embedded refugees, and identifies factors shaping these caregiving experiences, to inform the design and development of potentially appropriate ECD interventions. METHODS: A qualitative formative study, which included 14 focus group discussions (n = 125 participants), and 13 key informant interviews was conducted between August and October 2018. Purposive sampling approaches were used to select a diverse range of respondents including caregivers of children below three years of age and stakeholders of Kenyan nationality and refugees. Data were analysed using a thematic approach and the Nurturing Care Framework was used as an interpretative lens. RESULTS: There was a fusion of traditional, religious and modern practices in the care for young children, influenced by the caregivers' culture, and financial disposition. There were mixed views/practices on nutrition for young children. For example, while there was recognition of the value for breastfeeding, working mothers, especially in the informal economy, found it a difficult practice. Stimulation through play was common, especially for older children, but gaps were identified in aspects such as reading, and storytelling in the home environment. Some barriers identified included the limited availability of a caregiver, insecurity, and confined space in the informal settlement, all of which made it difficult for children to engage in play activities. Physical and psychological forms of discipline were commonly mentioned, although few caregivers practiced and recognized the need for using non-violent approaches. Some overarching challenges for caregivers were unemployment or unstable sources of income, and, particularly for refugee caregivers, their legal status. CONCLUSION: These findings point to the interplay of various factors affecting optimal caregiving for young children in an urban informal settlement with Kenyans and refugees. Integrated ECD interventions are needed for such a mixed population, especially those that strive to anchor along caregivers' social support system, co-designed together with community stakeholders, that ideally focus on parent skills training promoting nurturing care and economic empowerment.
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Cuidadores , Desarrollo Infantil , Grupos Focales , Investigación Cualitativa , Refugiados , Humanos , Kenia , Refugiados/psicología , Preescolar , Femenino , Masculino , Cuidadores/psicología , Lactante , AdultoRESUMEN
2D materials offer the ability to expose their electronic structure to manipulations by a proximity effect. This could be harnessed to craft properties of 2D interfaces and van der Waals heterostructures in devices and quantum materials. We explore the possibility to create an artificial spin polarized electrode from graphene through proximity interaction with a ferromagnetic insulator to be used in a magnetic tunnel junction (MTJ). Ferromagnetic insulator/graphene artificial electrodes were fabricated and integrated in MTJs based on spin analyzers. Evidence of the emergence of spin polarization in proximitized graphene layers was observed through the occurrence of tunnel magnetoresistance. We deduced a spin dependent splitting of graphene's Dirac band structure (â¼15 meV) induced by the proximity effect, potentially leading to full spin polarization and opening the way to gating. The extracted spin signals illustrate the potential of 2D quantum materials based on proximity effects to craft spintronics functionalities, from vertical MTJs memory cells to logic circuits.
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Despite screening programmes, numerous clinical studies and new breast imaging techniques, breast cancer incidence for women continues to rise. The arrival of predictive and personalized medicine could clearly redefine our screening recommendations. One promising approach to improving screening would be to use tools to predict the risk of developing breast cancer, including polygenic risk scores (PRS). This approach will enable us to offer women risk-based screening by adapting the frequency, type and age of screening. This article reviews some definitions of the PRS and breast cancer screening. We also explain the risk assessment models that have been developed and the various studies underway on personalized screening.
Malgré les programmes de dépistage, les nombreuses études cliniques et les nouvelles techniques d'imagerie mammaire, l'incidence du cancer du sein chez la femme continue à augmenter. L'arrivée de la médecine prédictive et personnalisée pourrait clairement redéfinir nos recommandations de dépistage. Une des approches prometteuses pour améliorer le dépistage serait d'utiliser les outils de prédiction du risque de développer un cancer du sein en incluant les scores de risques polygéniques (PRS). Cette approche permettra de proposer aux femmes un dépistage basé sur le risque en adaptant la fréquence des examens ainsi que le type et l'âge du début du dépistage. Cet article reprend quelques définitions concernant le PRS et le dépistage du cancer sein. Nous allons passer en revue les modèles de prédiction de risque qui ont été développés et les différentes études en cours sur le dépistage personnalisé.
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Neoplasias de la Mama , Detección Precoz del Cáncer , Medicina Preventiva , Humanos , Neoplasias de la Mama/genética , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/prevención & control , Femenino , Detección Precoz del Cáncer/métodos , Medición de Riesgo , Medicina Preventiva/métodos , Herencia Multifactorial , Predisposición Genética a la Enfermedad , Puntuación de Riesgo GenéticoRESUMEN
Abnormal retention of mitochondria in mature red blood cells (RBC) has been recently reported in sickle cell anemia (SCA) but their functionality and their role in the pathophysiology of SCA remain unknown. The presence of mitochondria within RBC was determined by flow cytometry in 61 SCA patients and ten healthy donors. Patients were classified according to the percentage of mature RBC with mitochondria contained in the whole RBC population: low (0-4%), moderate (>4% and <8%), or high level (>8%). RBC rheological, hematological, senescence and oxidative stress markers were compared between the three groups. RBC senescence and oxidative stress markers were also compared between mature RBC containing mitochondria and those without. The functionality of residual mitochondria in sickle RBC was measured by high-resolution respirometry assay and showed detectable mitochondrial oxygen consumption in sickle mature RBC but not in healthy RBC. Increased levels of mitochondrial reactive oxygen species were observed in mature sickle RBC when incubated with Antimycin A versus without. In addition, mature RBC retaining mitochondria exhibited greater levels of reactive oxygen species compared to RBC without mitochondria, as well as greater Ca2+, lower CD47 and greater phosphatidylserine exposure. Hematocrit and RBC deformability were lower, and the propensity of RBC to sickle under deoxygenation was higher, in the SCA group with a high percentage of mitochondria retention in mature RBC. This study showed the presence of functional mitochondria in mature sickle RBC, which could favor RBC sickling and accelerate RBC senescence, leading to increased cellular fragility and hemolysis.
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Anemia de Células Falciformes , Hemólisis , Humanos , Especies Reactivas de Oxígeno , Eritrocitos , Estrés Oxidativo , MitocondriasRESUMEN
KEY MESSAGE: Multi-trial genome wide association study of plasticity indices allow to detect QTLs specifically involved in the genotype x water availability interaction. Concerns regarding high maize yield losses due to increasing occurrences of drought events are growing, and breeders are still looking for molecular markers for drought tolerance. However, the genetic determinism of traits in response to drought is highly complex and identification of causal regions is a tremendous task. Here, we exploit the phenotypic data obtained from four trials carried out on a phenotyping platform, where a diversity panel of 254 maize hybrids was grown under well-watered and water deficit conditions, to investigate the genetic bases of the drought response in maize. To dissociate drought effect from other environmental factors, we performed multi-trial genome-wide association study on well-watered and water deficit phenotypic means, and on phenotypic plasticity indices computed from measurements made for six ecophysiological traits. We identify 102 QTLs and 40 plasticity QTLs. Most of them were new compared to those obtained from a previous study on the same dataset. Our results show that plasticity QTLs cover genetic regions not identified by QTLs. Furthermore, for all ecophysiological traits, except one, plasticity QTLs are specifically involved in the genotype by water availability interaction, for which they explain between 60 and 100% of the variance. Altogether, QTLs and plasticity QTLs captured more than 75% of the genotype by water availability interaction variance, and allowed to find new genetic regions. Overall, our results demonstrate the importance of considering phenotypic plasticity to decipher the genetic architecture of trait response to stress.
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Agua , Zea mays , Zea mays/genética , Estudio de Asociación del Genoma Completo , Sitios de Carácter Cuantitativo , Genotipo , Fenotipo , SequíasRESUMEN
OBJECTIVES: To develop a visual ensemble selection of deep convolutional neural networks (CNN) for 3D segmentation of breast tumors using T1-weighted dynamic contrast-enhanced (T1-DCE) MRI. METHODS: Multi-center 3D T1-DCE MRI (n = 141) were acquired for a cohort of patients diagnosed with locally advanced or aggressive breast cancer. Tumor lesions of 111 scans were equally divided between two radiologists and segmented for training. The additional 30 scans were segmented independently by both radiologists for testing. Three 3D U-Net models were trained using either post-contrast images or a combination of post-contrast and subtraction images fused at either the image or the feature level. Segmentation accuracy was evaluated quantitatively using the Dice similarity coefficient (DSC) and the Hausdorff distance (HD95) and scored qualitatively by a radiologist as excellent, useful, helpful, or unacceptable. Based on this score, a visual ensemble approach selecting the best segmentation among these three models was proposed. RESULTS: The mean and standard deviation of DSC and HD95 between the two radiologists were equal to 77.8 ± 10.0% and 5.2 ± 5.9 mm. Using the visual ensemble selection, a DSC and HD95 equal to 78.1 ± 16.2% and 14.1 ± 40.8 mm was reached. The qualitative assessment was excellent (resp. excellent or useful) in 50% (resp. 77%). CONCLUSION: Using subtraction images in addition to post-contrast images provided complementary information for 3D segmentation of breast lesions by CNN. A visual ensemble selection allowing the radiologist to select the most optimal segmentation obtained by the three 3D U-Net models achieved comparable results to inter-radiologist agreement, yielding 77% segmented volumes considered excellent or useful. KEY POINTS: ⢠Deep convolutional neural networks were developed using T1-weighted post-contrast and subtraction MRI to perform automated 3D segmentation of breast tumors. ⢠A visual ensemble selection allowing the radiologist to choose the best segmentation among the three 3D U-Net models outperformed each of the three models. ⢠The visual ensemble selection provided clinically useful segmentations in 77% of cases, potentially allowing for a valuable reduction of the manual 3D segmentation workload for the radiologist and greatly facilitating quantitative studies on non-invasive biomarker in breast MRI.
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Neoplasias de la Mama , Procesamiento de Imagen Asistido por Computador , Humanos , Femenino , Procesamiento de Imagen Asistido por Computador/métodos , Redes Neurales de la Computación , Mama/patología , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Imagen por Resonancia Magnética/métodosRESUMEN
OBJECTIVES: To evaluate the association between pretreatment MRI descriptors and breast cancer (BC) pathological complete response (pCR) to neoadjuvant chemotherapy (NAC). MATERIALS AND METHODS: Patients with BC treated by NAC with a breast MRI between 2016 and 2020 were included in this retrospective observational single-center study. MR studies were described using the standardized BI-RADS and breast edema score on T2-weighted MRI. Univariable and multivariable logistic regression analyses were performed to assess variables association with pCR according to residual cancer burden. Random forest classifiers were trained to predict pCR on a random split including 70% of the database and were validated on the remaining cases. RESULTS: Among 129 BC, 59 (46%) achieved pCR after NAC (luminal (n = 7/37, 19%), triple negative (n = 30/55, 55%), HER2 + (n = 22/37, 59%)). Clinical and biological items associated with pCR were BC subtype (p < 0.001), T stage 0/I/II (p = 0.008), higher Ki67 (p = 0.005), and higher tumor-infiltrating lymphocytes levels (p = 0.016). Univariate analysis showed that the following MRI features, oval or round shape (p = 0.047), unifocality (p = 0.026), non-spiculated margins (p = 0.018), no associated non-mass enhancement (p = 0.024), and a lower MRI size (p = 0.031), were significantly associated with pCR. Unifocality and non-spiculated margins remained independently associated with pCR at multivariable analysis. Adding significant MRI features to clinicobiological variables in random forest classifiers significantly increased sensitivity (0.67 versus 0.62), specificity (0.69 versus 0.67), and precision (0.71 versus 0.67) for pCR prediction. CONCLUSION: Non-spiculated margins and unifocality are independently associated with pCR and can increase models performance to predict BC response to NAC. CLINICAL RELEVANCE STATEMENT: A multimodal approach integrating pretreatment MRI features with clinicobiological predictors, including tumor-infiltrating lymphocytes, could be employed to develop machine learning models for identifying patients at risk of non-response. This may enable consideration of alternative therapeutic strategies to optimize treatment outcomes. KEY POINTS: ⢠Unifocality and non-spiculated margins are independently associated with pCR at multivariable logistic regression analysis. ⢠Breast edema score is associated with MR tumor size and TIL expression, not only in TN BC as previously reported, but also in luminal BC. ⢠Adding significant MRI features to clinicobiological variables in machine learning classifiers significantly increased sensitivity, specificity, and precision for pCR prediction.
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Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Terapia Neoadyuvante , Estudios Retrospectivos , Imagen por Resonancia Magnética , Resultado del Tratamiento , Edema/etiologíaRESUMEN
Silver has been used for its antimicrobial properties to fight infection for thousands of years. Unfortunately, some Gram-negative bacteria have developed silver resistance causing the death of patients in a burn unit. The genes responsible for silver resistance have been designated as the sil operon. Among the proteins of the sil operon, SilE has been shown to play a key role in bacterial silver resistance. Based on the limited information available, it has been depicted as an intrinsically disordered protein that folds into helices upon silver ion binding. Herein, this work demonstrates that SilE is composed of 4 clearly identified helical segments in the presence of several silver ions. The combination of analytical and biophysical techniques (NMR spectroscopy, CD, SAXS, HRMS, CE-ICP-MS, and IM-MS) reveals that SilE harbors four strong silver binding sites among the eight sites available. We have also further evidenced that SilE does not adopt a globular structure but rather samples a large conformational space from elongated to more compact structures. This particular structural organization facilitates silver binding through much higher accessibility of the involved His and Met residues. These valuable results will advance our current understanding of the role of SilE in the silver efflux pump complex mechanism and will help in the future rational design of inhibitors to fight bacterial silver resistance.
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Antiinfecciosos , Plata , Humanos , Plata/química , Dispersión del Ángulo Pequeño , Farmacorresistencia Bacteriana/genética , Difracción de Rayos X , Antiinfecciosos/farmacologíaRESUMEN
Ten years ago, trans-gender people were looking for respectful and safe accompaniment. It was in this context of difficulty in finding answers that the Maison Dispersée de Santé de Lille began to set up a support service. The approach was immediately anchored in the gender transition pathway within primary care medicine, i.e. in access to local care. Caregivers and users, we build together our practice of health and care by meeting, debating, listening and sharing individual and collective expertise. Thus, we have gradually built a rigorous and non-rigid framework of a global, bio-psycho-social accompaniment that takes into account experiential learning. This framework must take into account the health of each individual in order to propose, follow and adapt a hormone replacement treatment. It allows for the accompaniment of physical changes, possible pre-existing psychological suffering or that which appears during the transition, as well as the upheaval of one's place in society. People with gender variations need medical support because they are part of a social reality that leads to this demand. The prevalence of transidentity has long been underestimated and this need has also been underestimated. Our experience of more than ten years of accompanying transitions of women and men in this context shows the feasibility of transitions in primary care within the French system of care and medico social support.
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Cuidadores , Apoyo Social , Masculino , Humanos , Femenino , Retroalimentación , Estudios de Seguimiento , Cuidadores/psicología , Atención Primaria de SaludRESUMEN
The aim of this study was to (1) analyze blood viscosity, red blood cell (RBC) deformability, and aggregation in hospitalized patients with Coronavirus disease 19 (COVID-19); (2) test the associations between impaired blood rheology and blood coagulation; and (3) test the associations between impaired blood rheology and several indicators of clinical severity. A total of 172 patients with COVID-19, hospitalized in COVID-unit of the Internal Medicine Department (Lyon, France) participated in this study between January and May 2021. Clinical parameters were collected for each patient. Routine hematological/biochemical parameters, blood viscosity, RBC deformability and aggregation, and RBC senescence markers were measured on the first day of hospitalization. A control group of 38 healthy individuals was constituted to compare the blood rheological and RBC profile. Rotational thromboelastography was performed in 76 patients to study clot formation dynamics. Our study demonstrated that patients with COVID-19 had increased blood viscosity despite lower hematocrit than healthy individuals, as well as increased RBC aggregation. In-vitro experiments demonstrated a strong contribution of plasma fibrinogen in this RBC hyper-aggregation. RBC aggregation correlated positively with clot firmness, negatively with clot formation time, and positively with the length of hospitalization. Patients with oxygen supplementation had higher RBC aggregation and blood viscosity than those without, and patients with pulmonary lesions had higher RBC aggregation and enhanced coagulation than those without. This study is the first to demonstrate blood hyper-viscosity and RBC hyper-aggregation in a large cohort of patients with COVID-19 and describe associations with enhanced coagulation and clinical outcomes.
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Viscosidad Sanguínea , COVID-19/sangre , Agregación Eritrocitaria , Eritrocitos/patología , Adulto , Anciano , Coagulación Sanguínea , COVID-19/diagnóstico , COVID-19/patología , Deformación Eritrocítica , Humanos , Persona de Mediana Edad , SARS-CoV-2/aislamiento & purificaciónRESUMEN
BACKGROUND: Community engagement is crucial for the design and implementation of community-based early childhood development (ECD) programmes. This paper aims to share key components and learnings of a community engagement process for an integrated ECD intervention. The lessons shared are drawn from a case study of urban informal settlement with embedded refugees in Nairobi, Kenya. METHODS: We conducted three stakeholder meetings with representatives from the Ministry of Health at County and Sub-County, actors in the ECD sector, and United Nations agency in refugee management, a transect walk across five villages (Ngando, Muslim, Congo, Riruta and Kivumbini); and, six debrief meetings by staff from the implementing organization. The specific steps and key activities undertaken, the challenges faced and benefits accrued from the community engagement process are highlighted drawing from the implementation team's perspective. RESULTS: Context relevant, well-planned community engagement approaches can be integrated into the five broad components of stakeholder engagement, formative research, identification of local resources, integration into local lives, and shared control/leadership with the local community. These can yield meaningful stakeholder buy-in, community support and trust, which are crucial for enabling ECD programme sustainability. CONCLUSION: Our experiences underscore that intervention research on ECD programmes in urban informal settlements requires a well-planned and custom-tailored community engagement model that is sensitive to the needs of each sub-group within the community to avoid unintentionally leaving anyone out.
Asunto(s)
Refugiados , Preescolar , Humanos , Kenia , Liderazgo , Evaluación de Programas y Proyectos de Salud , ConfianzaRESUMEN
OBJECTIVES: The Veterans Administration (VA) Mobility Screening and Solutions Tool (VA MSST) was developed to screen a patient's safe mobility level 'in the moment' and provide clinical decision support related to the use of safe patient handling and mobility (SPHM) equipment. This evidence-based flowchart tool is a common language tool that enables any healthcare worker at any time to accurately measure and communicate patient mobility and transfer equipment needs across disciplines and settings. METHODS: The VA MSST has four levels and differentiates between the need for powered and non-powered equipment depending on the patient's independence. Subject matter experts wrote scenarios for interrater reliability and validity testing. The initial VA MSST draft iteration was reviewed by 163 VA staff (mostly physical therapists and occupational therapists) amongst simulation scenarios and provided content validity, and additional insight and suggestions. Revisions were made to create the final VA MSST which was evaluated by over 200 healthcare workers from varied disciplines (including medical doctors, advanced practice registered nurses, registered nurses, licensed practical nurses, certified nursing assistants, occupational therapists, physical therapists, speech therapists, radiology and ultrasound technicians, etc.). An instruction video and eighteen scenario videos were embedded in an online survey. The survey intended to demonstrate the interrater reliability and validity (concurrent and construct) of the VA MSST. Over 500 VA staff (raters) received a survey invitation via email. RESULTS: Raters (N = 230) from multiple disciplines and healthcare settings independently screened patient mobility status for each of 18 scenarios using the VA MSST. The raters were diverse in their age and years of experience. The estimated interrater reliability (IRR) for VA MSST was excellent and statistically significant with an estimated Krippendorff's alpha (ICC (C, k)) of 0.998 [95% CI: 0.996-0.999]. Eighty-two percent of raters reported that overall VA MSST instructions were clear or very clear and understandable. VA MSST ratings made by technicians and nursing assistants group correlated strongly (r = 0.99, p < 0.001) with the 'gold standard' (experienced physical therapists), suggesting a high concurrent validity of the tool. The VA MSST significantly discriminated between the different levels of patient mobility required for safe mobilization as intended (each difference, p < 0.0001); this suggests a good construct validity. CONCLUSIONS: The VA MSST is an evidence-based flowchart screening and decision support tool that demonstrates excellent interrater reliability across disciplines and settings. VA MSST has strong face and content validity, as well as good concurrent and construct validity.