1,157 research outputs found

    Colloidal semiconductor/magnetic heterostructures based on iron-oxide-functionalized brookite TiO2 nanorods

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    A flexible colloidal seeded-growth strategy has been developed to synthesize all-oxide semiconductor/magnetic hybrid nanocrystals (HNCs) in various topological arrangements, for which the dimensions of the constituent material domains can be controlled independently over a wide range. Our approach relies on driving preferential heterogeneous nucleation and growth of spinel cubic iron oxide (IO) domains onto brookite TiO2 nanorods (b-TiO2) with tailored geometric parameters, by means of time-programmed delivery of organometallic precursors into a suitable TiO2-loaded surfactant environment. The b-TiO2 seeds exhibit size-dependent accessibility towards IO under diffusion-controlled growth regime, which allows attainment of HNCs individually made of a single b-TiO2 section functionalized with either one or multiple nearly spherical IO domains. In spite of the dissimilarity of the respective crystal-phases, the two materials share large interfacial junctions without significant lattice strain being induced across the heterostructures. The synthetic achievements have been supported by a systematic morphological, compositional and structural characterization of the as-prepared HNCs, offering a mechanistic insight into the specific role of the seeds in the control of heterostructure formation in liquid media. In addition, the impact of the formed b-TiO2/IO heterojunctions on the magnetic properties of IO has also been assessed

    Architectural Control of Seeded-Grown Magnetic−Semicondutor Iron Oxide−TiO2 Nanorod Heterostructures: The Role of Seeds in Topology Selection

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    A colloidal nonaqueous approach to semiconductor−magnetic hybrid nanocrystals (HNCs) with selectable heterodimer topologies and tunable geometric parameters is demonstrated. Brookite TiO2 nanorods, distinguished by a curved shape-tapered profile with richly faceted terminations, are exploited as substrate seeds onto which a single spherical domain of inverse spinel iron oxide can be epitaxially grown at either one apex or any location along their longitudinal sidewalls in a hot surfactant environment. The topologically controlled arrangement of the component material lattices, the crystallographic relationships holding between them, and strain distribution across individual heterostructures have been studied by combining X-ray diffraction and absorption techniques with high-resolution transmission electron microscopy investigations. Supported by such structural knowledge, the synthetic achievements are interpreted within the frame of various mechanistic models offering complementary views of HNC formation..

    Room Temperature In-plane <100> Magnetic Easy Axis for Fe3O4/SrTiO3(001):Nb Grown by Infrared PLD

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    We examine the magnetic easy-axis directions of stoichiometric magnetite films grown on SrTiO3:Nb by infrared pulsed-laser deposition. Spin-polarized low-energy electron microscopy reveals that the individual magnetic domains are magnetized along the in-plane film directions. Magneto-optical Kerr effect measurements show that the maxima of the remanence and coercivity are also along in-plane film directions. This easy-axis orientation differs from bulk magnetite and films prepared by other techniques, establishing that the magnetic anisotropy can be tuned by film growth.Comment: 3 pages, 3 figure

    Influence of the Human Development Index on the Maternal–Perinatal Morbidity and Mortality of Pregnant Women with SARS-CoV-2 Infection: Importance for Personalized Medical Care

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    This study (FIS-PI18/00912) was supported by the Instituto de Salud Carlos III (Plan Estatal de I + D + i 2013–2016) and cofinanced by the European Development Regional Fund ‘‘A way to achieve Europe’’ (ERDF) and B2017/BMD-3804 MITIC-CM.Coronavirus disease-19 (COVID-19) is perhaps the most worrisome pandemic in the 21st century, having entailed devastating consequences for the whole society during the last year. Different studies have displayed an existing association between pregnancy and COVID-19 severity due to the various physiological changes that occur during gestation. Recent data identified maternal country of origin as an important determinant of COVID-19 presentation in pregnant women. However, the explanation of this fact remains to be fully elucidated. Therefore, the purpose of this work is to analyze the possible relationship between Human Development Index (HDI) of maternal country of origin with the morbimortality of pregnant women and their newborns. Here, we conducted a multicentric, ambispective, observational case-control study (1:1 ratio) and compare with the HDI of each country (group 1—very high HDI, group 2—high HDI, group 3—medium HDI, and group 4—low HDI). In total, 1347 pregnant women with confirmed SARV-CoV-2 infection (cases) were enrolled, and each was paired with one control to give a total number of 2694 participants from 81 tertiary care centers. Among the women with SARS-CoV-2 infection, more cases were produced of perinatal mortality, overall maternal morbidity, COVID-19 maternal morbidity, C-sections, hypertensive maternal morbidity, and perinatal morbidity. Our results described an inverse association between HDI and maternofetal morbidity and mortality. Moreover, the countries with an HDI lower than 1 showed higher rates of patients with maternal COVID-19-related morbidity (6.0% vs. 2.4%, p < 0.001), a need for oxygen therapy (4.7% vs. 1.8%, p < 0.001), and maternal ICU admission (2.6% vs. 1.0%, p = 0.007). Compared to other risk factors such as overweight, obesity, preexisting and obstetric comorbidities, HDI emerged as an independent risk factor explaining much of the increased maternal–perinatal morbidity and mortality detected in our group of cases. Further research is needed to establish to confirm the real impact of this factor and its components on pregnancy outcomes.Depto. de Salud Pública y Materno - InfantilFac. de MedicinaTRUEUnión EuropeaComunidad de MadridInstituto de Salud Carlos IIIpu

    A pediatric regimen for adolescents and young adults with Philadelphia chromosome‐negative acute lymphoblastic leukemia: Results of the ALLRE08 PETHEMA trial

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    Background: Pediatric-based or -inspired trials have improved the prognosis of adolescents and young adults (AYA) with Philadelphia chromosome-negative (Ph-neg) acute lymphoblastic leukemia (ALL). Methods: This study reports the results of treatment of the ALLRE08 trial, a full pediatric trial for AYA aged 15-30 years with standard-risk (SR) ALL. Results: From 2008 to 2018, 89 patients (38 adolescents [15-18 years] and 51 young adults [YA, 19-30 years], median age: 20 [15-29] years) were enrolled in the ALLRE08 trial. The complete response (CR) was 95%. Twenty-two patients were transferred to a high-risk (HR) protocol because of poor marrow response on day 14 (n = 20) or high-level of end-induction minimal residual response (MRD ≥ 0.25%, n = 2). Cumulative incidence of relapse (CIR) at 5 years was 35% (95%CI: 23%-47%), with significant differences between adolescents and YA: 13% (4%-28%) vs 52% (34%-67%), P = .012. No treatment-related mortality was observed in 66/66 patients following the ALLRE08 trial vs 3/23 patients moved to a HR trial. The estimated 5-year overall survival (OS) was 74% (95%CI: 63%-85%), with significantly higher rates for adolescents vs YA: 87% (95%CI: 74%-100%) vs 63% (46%-80%), P = .021. Although CIR or OS were lower in patients who were transferred to a HR trial, the differences were not statistically significant (CIR: 34% [21%-47%] vs 37% [14%-61%]; OS: 78% [66%-90%] vs 61% [31%;91%]). Conclusion: A full pediatric trial is feasible and effective for AYA with Ph-neg, SR-ALL, with better results for adolescents than for YA. Outcome of patients with poor early response rescued with a HR trial was not significantly inferior

    A pediatric regimen for adolescents and young adults with Philadelphia chromosome-negative acute lymphoblastic leukemia : Results of the ALLRE08 PETHEMA trial

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    Altres ajuts: Supported in part by grants from Fundació La Caixa and CIBERONC (JMHR and AO).Pediatric-based or -inspired trials have improved the prognosis of adolescents and young adults (AYA) with Philadelphia chromosome-negative (Ph-neg) acute lymphoblastic leukemia (ALL). This study reports the results of treatment of the ALLRE08 trial, a full pediatric trial for AYA aged 15-30 years with standard-risk (SR) ALL. From 2008 to 2018, 89 patients (38 adolescents [15-18 years] and 51 young adults [YA, 19-30 years], median age: 20 [15-29] years) were enrolled in the ALLRE08 trial. The complete response (CR) was 95%. Twenty-two patients were transferred to a high-risk (HR) protocol because of poor marrow response on day 14 (n = 20) or high-level of end-induction minimal residual response (MRD ≥ 0.25%, n = 2). Cumulative incidence of relapse (CIR) at 5 years was 35% (95%CI: 23%-47%), with significant differences between adolescents and YA: 13% (4%-28%) vs 52% (34%-67%), P = .012. No treatment-related mortality was observed in 66/66 patients following the ALLRE08 trial vs 3/23 patients moved to a HR trial. The estimated 5-year overall survival (OS) was 74% (95%CI: 63%-85%), with significantly higher rates for adolescents vs YA: 87% (95%CI: 74%-100%) vs 63% (46%-80%), P = .021. Although CIR or OS were lower in patients who were transferred to a HR trial, the differences were not statistically significant (CIR: 34% [21%-47%] vs 37% [14%-61%]; OS: 78% [66%-90%] vs 61% [31%;91%]). A full pediatric trial is feasible and effective for AYA with Ph-neg, SR-ALL, with better results for adolescents than for YA. Outcome of patients with poor early response rescued with a HR trial was not significantly inferior. A full pediatric trial is feasible and effective for adolescent and young adults with acute lymphoblastic leukemia, with better results for adolescents than for young adults. The outcome of patients showing poor early response was not significantly inferior than that observed for good responders after being transferred to a high-risk trial

    Lymphangioleiomyomatosis biomarkers linked to lung metastatic potential and cell stemness

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    Lymphangioleiomyomatosis (LAM) is a rare lung-metastasizing neoplasm caused by the proliferation of smooth muscle-like cells that commonly carry loss-of-function mutations in either the tuberous sclerosis complex 1 or 2 (TSC1 or TSC2) genes. While allosteric inhibition of the mechanistic target of rapamycin (mTOR) has shown substantial clinical benefit, complementary therapies are required to improve response and/or to treat specific patients. However, there is a lack of LAM biomarkers that could potentially be used to monitor the disease and to develop other targeted therapies. We hypothesized that the mediators of cancer metastasis to lung, particularly in breast cancer, also play a relevant role in LAM. Analyses across independent breast cancer datasets revealed associations between low TSC1/2 expression, altered mTOR complex 1 (mTORC1) pathway signaling, and metastasis to lung. Subsequently, immunohistochemical analyses of 23 LAM lesions revealed positivity in all cases for the lung metastasis mediators fascin 1 (FSCN1) and inhibitor of DNA binding 1 (ID1). Moreover, assessment of breast cancer stem or luminal progenitor cell biomarkers showed positivity in most LAM tissue for the aldehyde dehydrogenase 1 (ALDH1), integrin-ß3 (ITGB3/CD61), and/or the sex-determining region Y-box 9 (SOX9) proteins. The immunohistochemical analyses also provided evidence of heterogeneity between and within LAM cases. The analysis of Tsc2-deficient cells revealed relative over-expression of FSCN1 and ID1; however, Tsc2-deficient cells did not show higher sensitivity to ID1-based cancer inhibitors. Collectively, the results of this study reveal novel LAM biomarkers linked to breast cancer metastasis to lung and to cell stemness, which in turn might guide the assessment of additional or complementary therapeutic opportunities for LAM
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