27 research outputs found
High temperature magnetic stabilization of cobalt nanoparticles by an antiferromagnetic proximity effect
Thermal activation tends to destroy the magnetic stability of small magnetic
nanoparticles, with crucial implications in ultra-high density recording among
other applications. Here we demonstrate that low blocking temperature
ferromagnetic (FM) Co nanoparticles (TB<70 K) become magnetically stable above
400 K when embedded in a high N\'eel temperature antiferromagnetic (AFM) NiO
matrix. The origin of this remarkable TB enhancement is due to a magnetic
proximity effect between a thin CoO shell (with low N\'eel temperature, TN; and
high anisotropy, KAFM) surrounding the Co nanoparticles and the NiO matrix
(with high TN but low KAFM). This proximity effect yields an effective AFM with
an apparent TN beyond that of bulk CoO, and an enhanced anisotropy compared to
NiO. In turn, the Co core FM moment is stabilized against thermal fluctuations
via core-shell exchange-bias coupling, leading to the observed TB increase.
Mean-field calculations provide a semi-quantitative understanding of this
magnetic- proximity stabilization mechanism
Mast cells impair melanoma cell homing and metastasis by inhibiting HMGA1 secretion
Mast cells; Melanoma; MetastasisMastòcits; Melanoma; MetàstasiMastocitos; Melanoma; MetástasisMetastatic disease is the major cause of death from cancer. From the primary tumour, cells remotely prepare the environment of the future metastatic sites by secreted factors and extracellular vesicles. During this process, known as pre-metastatic niche formation, immune cells play a crucial role. Mast cells are haematopoietic bone marrow-derived innate immune cells whose function in lung immune response to invading tumours remains to be defined. We found reduced melanoma lung metastasis in mast cell-deficient mouse models (Wsh and MCTP5-Cre-RDTR), supporting a pro-metastatic role for mast cells in vivo. However, due to evidence pointing to their antitumorigenic role, we studied the impact of mast cells in melanoma cell function in vitro. Surprisingly, in vitro co-culture of bone-marrow-derived mast cells with melanoma cells showed that they have an intrinsic anti-metastatic activity. Mass spectrometry analysis of melanoma-mast cell co-cultures secretome showed that HMGA1 secretion by melanoma cells was significantly impaired. Consistently, HMGA1 knockdown in B16-F10 cells reduced their metastatic capacity in vivo. Importantly, analysis of HMGA1 expression in human melanoma tumours showed that metastatic tumours with high HMGA1 expression are associated with reduced overall and disease-free survival. Moreover, we show that HMGA1 is reduced in the nuclei and enriched in the cytoplasm of melanoma metastatic lesions when compared to primary tumours. These data suggest that high HMGA1 expression and secretion from melanoma cells promote metastatic behaviour. Targeting HMGA1 expression intrinsically or extrinsically by mast cells actions reduce melanoma metastasis. Our results pave the way to the use of HMGA1 as anti-metastatic target in melanoma as previously suggested in other cancer types.US NIH (R01-CA169416); Children's Cancer and Blood Foundation; Feldestein Foundation; Melanoma Research Alliance; Nancy C. and Daniel P. Paduano Foundation; Starr Foundation; Translational NeTwork for the CLinical application of Extracellular Vesicle
Genetic study of atypical femoral fractures using exome sequencing in three affected sisters and three unrelated patients
Objectives: Atypical femoral fractures (AFF) are rare, often related to long-term bisphosphonate (BPs) tre- atment. Their pathogenic mechanisms are not precisely known and there is no evidence to identify patients with a high risk of AFF. The aim of this work is to study the genetic bases of AFFs. Material and methods: Whole-exome sequencing was carried out on 3 sisters and 3 unrelated additional patients, all treated with BPs for more than 5 years. Low frequency, potentially pathogenic variants sha- red by the 3 sisters, were selected, were selected and a network of gene and protein interactions was constructed with the data found. Results: We identified 37 rare variants (in 34 genes) shared by the 3 sisters, some not previously descri- bed. The most striking variant was the p.Asp188Tyr mutation in the enzyme geranylgeranyl pyrophos- phate synthase (encoded by the GGPS1 gene), from the mevalonate pathway and essential for osteoclast function. Another noteworthy finding was two mutations (one in the 3 sisters and one in an unrelated patient) in the CYP1A1 gene, involved in the metabolism of steroids. We identified other variants that could also be involved in the susceptibility to AFFs or in the underlying osteoporotic phenotype, such as those present in the SYDE2, NGEF, COG4 and FN1 genes. Conclusions: Our data are compatible with a model where the accumulation of susceptibility variants could participate in the genetic basis of AFFs
ARIA 2016 : Care pathways implementing emerging technologies for predictive medicine in rhinitis and asthma across the life cycle
The Allergic Rhinitis and its Impact on Asthma (ARIA) initiative commenced during a World Health Organization workshop in 1999. The initial goals were (1) to propose a new allergic rhinitis classification, (2) to promote the concept of multi-morbidity in asthma and rhinitis and (3) to develop guidelines with all stakeholders that could be used globally for all countries and populations. ARIA-disseminated and implemented in over 70 countries globally-is now focusing on the implementation of emerging technologies for individualized and predictive medicine. MASK [MACVIA (Contre les Maladies Chroniques pour un Vieillissement Actif)-ARIA Sentinel NetworK] uses mobile technology to develop care pathways for the management of rhinitis and asthma by a multi-disciplinary group and by patients themselves. An app (Android and iOS) is available in 20 countries and 15 languages. It uses a visual analogue scale to assess symptom control and work productivity as well as a clinical decision support system. It is associated with an inter-operable tablet for physicians and other health care professionals. The scaling up strategy uses the recommendations of the European Innovation Partnership on Active and Healthy Ageing. The aim of the novel ARIA approach is to provide an active and healthy life to rhinitis sufferers, whatever their age, sex or socio-economic status, in order to reduce health and social inequalities incurred by the disease.Peer reviewe
ARIA 2016: Care pathways implementing emerging technologies for predictive medicine in rhinitis and asthma across the life cycle
The Allergic Rhinitis and its Impact on Asthma (ARIA) initiative commenced during a World Health Organization workshop in 1999. The initial goals were (1) to propose a new allergic rhinitis classification, (2) to promote the concept of multi-morbidity in asthma a
Erratum to: Scaling up strategies of the chronic respiratory disease programme of the European Innovation Partnership on Active and Healthy Ageing (Action Plan B3: Area 5)
Correlation between work impairment, scores of rhinitis severity and asthma using the MASK-air (R) App
Background In allergic rhinitis, a relevant outcome providing information on the effectiveness of interventions is needed. In MASK-air (Mobile Airways Sentinel Network), a visual analogue scale (VAS) for work is used as a relevant outcome. This study aimed to assess the performance of the work VAS work by comparing VAS work with other VAS measurements and symptom-medication scores obtained concurrently. Methods All consecutive MASK-air users in 23 countries from 1 June 2016 to 31 October 2018 were included (14 189 users; 205 904 days). Geolocalized users self-assessed daily symptom control using the touchscreen functionality on their smart phone to click on VAS scores (ranging from 0 to 100) for overall symptoms (global), nose, eyes, asthma and work. Two symptom-medication scores were used: the modified EAACI CSMS score and the MASK control score for rhinitis. To assess data quality, the intra-individual response variability (IRV) index was calculated. Results A strong correlation was observed between VAS work and other VAS. The highest levels for correlation with VAS work and variance explained in VAS work were found with VAS global, followed by VAS nose, eye and asthma. In comparison with VAS global, the mCSMS and MASK control score showed a lower correlation with VAS work. Results are unlikely to be explained by a low quality of data arising from repeated VAS measures. Conclusions VAS work correlates with other outcomes (VAS global, nose, eye and asthma) but less well with a symptom-medication score. VAS work should be considered as a potentially useful AR outcome in intervention studies.Peer reviewe
Allergic Rhinitis and its Impact on Asthma (ARIA) Phase 4 (2018) : Change management in allergic rhinitis and asthma multimorbidity using mobile technology
Allergic Rhinitis and its Impact on Asthma (ARIA) has evolved from a guideline by using the best approach to integrated care pathways using mobile technology in patients with allergic rhinitis (AR) and asthma multimorbidity. The proposed next phase of ARIA is change management, with the aim of providing an active and healthy life to patients with rhinitis and to those with asthma multimorbidity across the lifecycle irrespective of their sex or socioeconomic status to reduce health and social inequities incurred by the disease. ARIA has followed the 8-step model of Kotter to assess and implement the effect of rhinitis on asthma multimorbidity and to propose multimorbid guidelines. A second change management strategy is proposed by ARIA Phase 4 to increase self-medication and shared decision making in rhinitis and asthma multimorbidity. An innovation of ARIA has been the development and validation of information technology evidence-based tools (Mobile Airways Sentinel Network [MASK]) that can inform patient decisions on the basis of a self-care plan proposed by the health care professional.Peer reviewe
Adherence to treatment in allergic rhinitis using mobile technology. The MASK Study
Background: Mobile technology may help to better understand the adherence to treatment. MASK-rhinitis (Mobile Airways Sentinel NetworK for allergic rhinitis) is a patient-centred ICT system. A mobile phone app (the Allergy Diary) central to MASK is available in 22 countries. Objectives: To assess the adherence to treatment in allergic rhinitis patients using the Allergy Diary App. Methods: An observational cross-sectional study was carried out on all users who filled in the Allergy Diary from 1 January 2016 to 1 August 2017. Secondary adherence was assessed by using the modified Medication Possession Ratio (MPR) and the Proportion of days covered (PDC) approach. Results: A total of 12143 users were registered. A total of 6949 users reported at least one VAS data recording. Among them, 1887 users reported >= 7 VAS data. About 1195 subjects were included in the analysis of adherence. One hundred and thirty-six (11.28%) users were adherent (MPR >= 70% and PDC = 70% and PDC = 1.50) and 176 (14.60%) were switchers. On the other hand, 832 (69.05%) users were non-adherent to medications (MPR Conclusion and clinical relevance: Adherence to treatment is low. The relative efficacy of continuous vs on-demand treatment for allergic rhinitis symptoms is still a matter of debate. This study shows an approach for measuring retrospective adherence based on a mobile app. This also represents a novel approach for analysing medication-taking behaviour in a real-world setting.Peer reviewe
Magnetically-actuated mesoporous nanowires for enhanced heterogeneous catalysis
We study the optimization of the catalytic properties of entirely magnetic Co–Pt compact and mesoporous nanowires of different diameters (25–200 nm) by using magnetic actuation. The nanowires are a single-entity, robust, magnetic-catalyst with a huge catalytically-active surface area. We show that apart from conventional parameters, like the size and morphology of the nanowires, other factors can be optimized to enhance their catalytic activity. In particular, given the magnetic character of the nanowires, rotating magnetic fields are a very powerful approach to boost the performance of the catalyst. In particular, the magnetic field induces them to act as nano-stirrers, improving the local flow of material towards the active sites of the catalyst. We demonstrate the versatility of the procedure by optimizing (i) the degradation of different types of pollutants (4-nitrophenol and methylene blue) and (ii) hydrogen production. For example, by using as little as 0.1 mg mL−1 of 25 nm wide Co–Pt mesoporous nanowires (with ∼3 nm pore size) as catalysts, kinetic normalized constants knor as high as 20,667 and 21,750 s−1 g−1 for 4-nitrophenol and methylene blue reduction, respectively, are obtained. In addition, activity values for hydrogen production from borohydride are as high as 25.0 L H2 g−1 min−1, even at room temperature. These values outperform any current state-of-the-art proposed catalysis strategies for water remediation reactions by at least 10-times and are superior to most advanced approaches to generate hydrogen from borohydride. The recyclability of the nanowires together with the simplicity of the synthetic method makes this approach (using not only Co–Pt, but also other mesoporous magnetic catalysts) very appealing for very diverse types of catalytic applications. </p