645 research outputs found
Magnetic nanofibers for remotely triggered catalytic activity applied to the degradation of organic pollutants
This work reports on the fabrication and characterization of a novel type of electrospun magnetic nanofibers (MNFs), and their application as a magnetically-activable catalysts for degradation of organic pollutants. The magnetic stimulation capability for the catalytic action is provided by iron-manganese oxide (MnxFe2-xO4) magnetic nanoparticles (MNPs) embedded into electrospun polyacrylonitrile (PAN), which provides stability and chemical resistance. The MNPs (average size d = 40 ± 7 nm) were first obtained by a green and fast sonochemical route, and subsequently embedded into electrospun PAN nanofibers. The final MNFs showed an average diameter of 760 ± 150 nm, providing a superhydrophobic surface with contact angle (θc = 165°), as well as a considerable amount ( 50 % wt.) of embedded MNPs (Mn0.5Fe2.5O4), thermally stable up to temperatures of 330 °C. The catalytic Fe2+/3+/Mn2+/3+/4+ active centers on the MNPs of MNF’s surface could be remotely activated by alternating magnetic fields (AMF) to degrade the methyl blue (MB). Remarkable stability of the MNFs during heating under extreme pH conditions (3 80 %, after several cycles of reusing the same sample without any regeneration process. The capacity of these materials as a catalytic material with magnetic remote activation makes them appealing for those catalytic applications under conditions of darkness or restrained access, where photocatalytic reaction cannot be achieved
Simple Sonochemical Method to Optimize the Heating Efficiency of Magnetic Nanoparticles for Magnetic Fluid Hyperthermia
We developed a fast, single-step sonochemical strategy for the green manufacturing of magnetite (Fe3O4) magnetic nanoparticles (MNPs), using iron sulfate (FeSO4) as the sole source of iron and sodium hydroxide (Na(OH)) as the reducing agent in an aqueous medium. The designed methodology reduces the environmental impact of toxic chemical compounds and minimizes the infrastructure requirements and reaction times down to minutes. The Na(OH) concentration has been varied to optimize the final size and magnetic properties of the MNPs and to minimize the amount of corrosive byproducts of the reaction. The change in the starting FeSO4concentration (from 5.4 to 43.1 mM) changed the particle sizes from (20 ± 3) to (58 ± 8) nm. These magnetite MNPs are promising for biomedical applications due to their negative surface charge, good heating properties (˜324 ± 2 W/g), and low cytotoxic effects. These results indicate the potential of this controlled, easy, and rapid ultrasonic irradiation method to prepare nanomaterials with enhanced properties and good potential for use as magnetic hyperthermia agents
Sonochemical route for mesoporous silica-coated magnetic nanoparticles towards pH-triggered drug delivery system
This work reports a pH-triggered release system based on core@shell mesoporous magnetic nanoparticles (MNP@mSiO2) obtained using a simple and rapid ultrasound-assisted method. Performed characterization reveals magnetic cores of Fe2.9Mn0.1O4 (38 ± 6 nm) and specific loss power values adequate for hyperthermia (463 W/g), surrounded by a mesoporous silica shell (10 ± 2 nm) with large surface area (269 m2 g-1) functionalized with hydroxyl groups (-OH). MNP@mSiO2 were loaded with DOX and amino-silane grops, providing pH-triggered DOX release at acidic environments, driving by dipolar intermolecular interactions. The experimental DOX release kinetics at pH 5.5, 6.6 and 7.4 were determined and adjusted to Gompertz dissolution model (Nash–Sutcliffe efficiency coefficient (NSE>0.9)), where the only strongly pH-dependent variable is the percentage of DOX released. The pH-triggered response observed in the system was ~20% of the DOX loaded into the MNP@mSiO2 is released at pH 6.6 or 7.4, whereas up to 80 wt% is released at pH 5.5. Time to 50% of release and dissociation rate of the system remaining constant, suggesting no-pH influence on these parameters. The biological assays highlight negligible hemolytic effect and cytocompatibility of the hybrid material, pointing out the potential use of MNP@mSiO2 as a magnetic driven drug delivery system with pH-triggered drug release kinetics at acidic environments. These results probe the feasibility of sonochemical methods in the elaboration of biocompatible and controlled properties nanomaterials for drug release applications, with the advantage of accurately responses predictions by mathematical model and using minimal processing steps or laboratory equipment. © 2021 The Author
Cross-country migration linked to people who inject drugs challenges the long-term impact of national HCV elimination programmes
To the Editor:
As of 2018, the majority of Western European countries – including Spain – have lifted restrictions to therapy based on disease severity in the context of HCV infections.1 Long overdue, most national elimination programmes now also include access to care for people who inject drugs (PWID), 2 who are at the core of ongoing HCV transmission.3 Macías et al.4 have recently shown in this Journal that high viral cure rates can be achieved in this group, hereby providing evidence that targeting PWID in treatment programmes is worthwhile. However, the extent to which such national efforts can reduce the HCV burden not only depends on the uptake into care and treatment success rates, it is also determined by the relative importance of within-country transmission and virus importation from elsewhere.
As the chronic nature of most HCV infections hampers reliably reconstructing contact networks from patient interviews, virus genetic data can be a valuable alternative source of information for elucidating the geographic history of virus lineages (e.g. [5], [6]). Using such data, we have recently shown that for the most prevalent subtype among PWID in Spain (40%, 7), HCV1a, infections often link to infections abroad – in recent years >50% link to Western European countries, mostly European Union (EU) member states – as opposed to other infections ..
Friction, nanowear and corrosion properties of electroplated nickel surfaces after dual implantation of Cr+ and N2+ ions. Influence of the implantation energy of the N2+ ions
The lithium stellarator experiment. TJ-II as a benchmark
In the last years, lithium wall conditioning has been carried out in several fusion devices (Tokamaks, Compact Toruses) by different techniques, providing in many instances record values of plasma parameters and enhanced plasma reproducibility. Behind these findings are the low recycling, low contamination and non-coronal enhanced radiative power dissipation properties of Li. Stellarators are best suited for reactor concepts as far as they basically free from extreme thermal load events. However, the potential problem of impurity accumulation must be taken into account. Therefore, the use of low Z elements as PFC would be highly desirable. In the present work, the plasma performance of the TJ-II Heliac under Li-coated wall conditions with lithium is described. Compared to previous coatings, lithium has produced the best plasma performance to date, leading to the achievement of record values in plasma density and energy confinement. In the present work, the impact of the Li coating operation on reactor relevant issues, such as particle exhaust and retention, high-density operation, confinement characteristics and plasma wall interaction issues is stressed.На протязі останніх років обробку стінок літієм було проведено в кількох термоядерних установках (токамаки, компактні тори) з використанням різних методів, що забезпечило у багатьох випадках одержання плазми з рекордними параметрами та покращеним відтворенням результатів. Ці результати пов’язані з низьким рециклінгом, що властивий літію, слабким забрудненням плазми і підвищеним не корональним поглинанням випромінювання. Стеларатори краще за все підходять для концепції реактора, бо в них у принципі не може бути підвищених теплових навантажень. Але треба враховувати можливість накопичення домішок. Тому конче бажано в поверхнях, які повернені до плазми, використовувати елементи з низьким Z. В даній роботі описано експерименти по одержанню плазми в геліаку TJ-II в умовах покриття стінок літієм. Порівняно з покриттями, що використовувалися раніше, літій забезпечив одержання плазми з найкращими на даний час параметрами, дозволивши досягти рекордних значень гущини плазми та утримання енергії. Підкреслена важливість літієвого покриття для таких аспектів реактора, як втрати і затримування частинок, робота при високій гущині, характеристики утримання та взаємодія плазма-стінка.В течение последних лет обработка стенок литием была проведена в нескольких термоядерных установках (токамаки, компактные торы) с использованием различных методов, что обеспечило во многих случаях получение плазмы с рекордными параметрами и улучшенной воспроизводимостью результатов. Эти результаты связаны со свойственными литию низким рециклингом, слабым загрязнением плазмы и повышенным не корональным поглощением излучения. Стеллараторы лучше всего подходят для концепции реактора, ибо у них в принципе не может быть повышенных тепловых нагрузок. Однако, необходимо учитывать возможность накопления примесей. Поэтому весьма желательно в поверхностях, обращённых к плазме, использовать элементы с низким Z. В настоящей работе описаны эксперименты по получению плазмы в гелиаке TJ-II в условиях покрытия стенок литием. По сравнению с покрытиями, которые использовались раньше, литий обеспечил получение плазмы с наилучшими в настоящее время параметрами, позволив достичь рекордных значений плотности плазмы и удержания энергии. Подчёркивается важность литиевого покрытия для таких аспектов реактора, как расход и удерживание частиц, работа при большой плотности, характеристики удержания и взаимодействие плазма-стенка
Exploring Health Science Students’ Notions on Organ Donation and Transplantation: A Multicenter Study
The knowledge acquired during university education about organ donation and transplantation (ODT) decisively influences the information future health professionals transmit. This is important in ODT where the participation of the general public is essential to obtain organs. Objective: To determine notions of Spanish medicine and nursing students on ODT and its relationship with attitude toward ODT. Methods and Design: and design. We conducted a sociologic, multicenter, and observational study. The population for our study consisted of medical and nursing students in Spanish universities. Our database was the Collaborative International Donor Project, stratified by geographic area and academic course. A validated questionnaire (PCID-DTO-RIOS) was self-administered and completed anonymously. Our sample consisted of 9598 medical and 10, 566 nursing students (99% confidence interval; precision of ±1%), stratified by geographic area and year of study. Results: The completion rate for our study was 90%. Only 20% (n=3640) of students thought their notions on ODT were good; 41% (n=7531) thought their notions were normal; 36% (n=6550) thought their notions were scarce. Comparing groups, there were differences between those who believed that their notions on ODT were good (44% nursing vs 56% medical students; P < .000), and those who believed it scarce (54% nursing vs 46% medical students; P < .000). Notions on ODT were related with attitude toward the donation of one''s own organs: those who considered their notions were good were more in favor then those who considered it scarce (88% vs 72%; P < .000). Conclusion: Only 20% of Spanish medical and nursing students thought their notions on ODT were good. Having good knowledge is related to a favorable attitude towards ODT. Receiving specific information on the subject could improve their knowledge about ODT during their training
Pathological response in a triple-negative breast cancer cohort treated with neoadjuvant carboplatin and docetaxel according to Lehmann's refined classification
Purpose: Triple-negative breast cancer (TNBC) requires the identification of reliable predictors of response to neoadjuvant chemotherapy (NACT). For this purpose, we aimed to evaluate the performance of the TNBCtype-4 classifier in a cohort of patients with TNBC treated with neoadjuvant carboplatin and docetaxel (TCb). Methods: Patients with TNBC were accrued in a nonrandomized trial of neoadjuvant carboplatin AUC 6 and docetaxel 75 mg/m2 for six cycles. Response was evaluated in terms of pathologic complete response (pCR, ypT0/is ypN0) and residual cancer burden by Symmans and colleagues. Lehmann's subtyping was performed using the TNBCtype online tool from RNAseq data, and germline sequencing of a panel of seven DNA damage repair genes was conducted. Results: Ninety-four out of the 121 patients enrolled in the trial had RNAseq available. The overall pCR rate was 44.7%. Lehmann subtype distribution was 34.0% BL1, 20.2% BL2, 23.4% M, 14.9% LAR, and 7.4% were classified as ERþ. Response to NACT with TCb was significantly associated with Lehmann subtype (P ¼ 0.027), even in multivariate analysis including tumor size and nodal involvement, with BL1 patients achieving the highest pCR rate (65.6%), followed by BL2 (47.4%), M (36.4%), and LAR (21.4%). BL1 was associated with a significant younger age at diagnosis and higher ki67 values. Among our 10 germline mutation carriers, 30% were BL1, 40% were BL2, and 30% were M. Conclusions: TNBCtype-4 is associated with significantly different pCR rates for the different subtypes, with BL1 and LAR displaying the best and worse responses to NACT, respectively
Diet quality index as a predictor of treatment efficacy in overweight and obese adolescents: The EVASYON study
Background & aim: A diet quality index (DQI) is a tool that provides an overall score of an individual''s dietary intake when assessing compliance with food-based dietary guidelines. A number of DQIs have emerged, albeit their associations with health-related outcomes are debated. The aim of the present study was to assess whether adherence to dietary intervention, and the overall quality of the diet, can predict body composition changes. Methods: To this purpose, overweight/obese adolescents (n = 117, aged: 13–16 years; 51 males, 66 females) were recruited into a multi-component (diet, physical activity and psychological support) family-based group treatment programme. We measured the adolescents’ compliance and body composition at baseline and after 2 months (intensive phase) and 13 months (extensive phase) of follow-up. Also, at baseline, after 6 months, and at the end of follow-up we calculated the DQI. Results: Global compliance with the dietary intervention was 37.4% during the intensive phase, and 14.3% during the extensive phase. Physical activity compliance was 94.1% at 2-months and 34.7% at 13months and psychological support compliance were growing over the intervention period (10.3% intensive phase and 45.3% during extensive phase). Adolescents complying with the meal frequency criteria at the end of the extensive phase had greater reductions in FMI z-scores than those did not complying (Cohen''s d = 0.53). A statistically significant association was observed with the diet quality index. DQI-A variation explained 98.1% of BMI z-score changes and 95.1% of FMI changes. Conclusions: We conclude that assessment of changes in diet quality could be a useful tool in predicting body composition changes in obese adolescents involved in a diet and physical activity intervention programme backed-up by psychological and family support
Influence of the length of hospitalisation in post-discharge outcomes in patients with acute heart failure: Results of the LOHRCA study
Objective: To investigate the relationship between length of hospitalisation (LOH) and post-discharge outcomes in acute heart failure (AHF) patients and to ascertain whether there are different patterns according to department of initial hospitalisation.
Methods: Consecutive AHF patients hospitalised in 41 Spanish centres were grouped based on the LOH (15 days). Outcomes were defined as 90-day post-discharge all-cause mortality, AHF readmissions, and the combination of both. Hazard ratios (HRs), adjusted by chronic conditions and severity of decompensation, were calculated for groups with LOH >6 days vs. LOH <6 days (reference), and stratified by hospitalisation in cardiology, internal medicine, geriatrics, or short-stay units.
Results: We included 8563 patients (mean age: 80 (SD = 10) years, 55.5% women), with a median LOH of 7 days (IQR 4–11): 2934 (34.3%) had a LOH 15 days. The 90-day post-discharge mortality was 11.4%, readmission 32.2%, and combined endpoint 37.4%. Mortality was increased by 36.5% (95%CI = 13.0–64.9) when LOH was 11–15 days, and by 72.0% (95%CI = 42.6–107.5) when >15 days. Conversely, no differences were found in readmission risk, and the combined endpoint only increased 21.6% (95%CI = 8.4–36.4) for LOH >15 days. Stratified analysis by hospitalisation departments rendered similar post-discharge outcomes, with all exhibiting increased mortality for LOH >15 days and no significant increments in readmission risk.
Conclusions: Short hospitalisations are not associated with worse outcomes. While post-discharge readmissions are not affected by LOH, mortality risk increases as the LOH lengthens. These findings were similar across hospitalisation departments
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