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Luis Cea-Calvo,1 Ignacio Marín-Jiménez,2 Javier de Toro,3 María J Fuster-RuizdeApodaca,4,5 Gonzalo Fernández,1 Nuria Sánchez-Vega,1 Domingo Orozco-Beltrán6 1Medical Affairs Department, MSD Spain, Madrid, Spain; 2IBD Unit, Gastroenterology Department, Clinical Research Institute Gregorio Marañón (IiSGM), Gregorio Marañón University Hospital, Madrid, Spain; 3Rheumatology Department, A Coruña University Hospital, A Coruña, Spain; 4SEISIDA (Spanish AIDS Multidisciplinary Society), Madrid, Spain; 5Department of Social and Organizational Psychology, Universidad Nacional de Educación a Distancia (UNED), Madrid, Spain; 6Clinical Medicine Department, Miguel Hernandez University, San Juan de Alicante, SpainCorrespondence: Luis Cea-CalvoMedical Affairs Department, MSD Spain, Josefa Valcárcel 38, Madrid 28027, SpainTel +34 913210740Email luis.cea@merck.comPurpose: To investigate relationships between intentional and non-intentional non-adherence behaviors and patient experience with healthcare and beliefs in medications.Patients and Methods: This is a post hoc analysis of a cross-sectional anonymous survey distributed between May and September 2017 to patients with rheumatic disease, inflammatory bowel disease, HIV infection or diabetes mellitus from outpatient and primary care clinics in Spain. Patients answered five questions about non-adherence behaviors and completed questionnaires on their experience with healthcare (IEXPAC: Instrument to Evaluate the EXperience of PAtients with Chronic diseases) and beliefs about medicines (BMQ: Beliefs About Medicines Questionnaire).Results: Among 1530 respondents, 53% showed ≥ 1 non-adherence behavior; 35% had ≥ 1 non-intentional non-adherence behavior, and 33% had ≥ 1 intentional non-adherence behavior. Patients with HIV infection had the lowest frequency of intentional non-adherence behaviors. Non-intentional non-adherence was associated with patient beliefs (inversely with BMQ overall score) and patient experiences (inversely with IEXPAC Factor 3 sub-score, self-management). Intentional non-adherence was strongly associated with beliefs scores (directly with BMQ concerns and inversely with BMQ necessity sub-score) and inversely associated with HIV infection.Conclusion: The different associations of intentional and non-intentional non-adherence behaviors found in this study help to understand how patient experiences and beliefs influence medical non-adherence, and in the development of strategies for reducing non-adherence.Keywords: BMQ, chronic disease, IEXPAC, intentional behavior, medication adherence, patient beliefs

Carlos M González,1 Loreto Carmona,2 Javier de Toro,3 Enrique Batlle-Gualda,4 Antonio I Torralba,5 María J Arteaga,6 Luis Cea-Calvo6 1Department of Rheumatology, Gregorio Marañón Hospital, 2Instituto de Salud Musculoesquelética, Madrid, 3Department of Rheumatology, Hospital Universitario A Coruña, A Coruña, 4Department of Rheumatology, Hospital Universitario de Sant Joan d’Alacant, Alicante, 5Coordinadora Nacional de Artritis, 6Medical Affairs Department, Merck Sharp & Dohme, Madrid, Spain Objective: The aim of this study was to explore perceptions of patients with rheumatic diseases treated with subcutaneous (SC) biological drugs on the impact on daily life and satisfaction with current therapy, including preferred attributes. Methods: A survey was developed ad hoc by four rheumatologists and three patients, including Likert questions on the impact of disease and treatment on daily life and preferred attributes of treatment. Rheumatologists from 50 participating centers were instructed to handout the survey to 20 consecutive patients with rheumatoid arthritis (RA), axial spondyloarthritis (ax-SpA), or psoriatic arthritis (PsA) receiving SC biological drugs. Patients responded to the survey at home and sent it to a central facility by prepaid mail. Results: A total of 592 patients returned the survey (response rate: 59.2%), 51.4% of whom had RA, 23.8% had ax-SpA, and 19.6% had PsA. Patients reported moderate-to-severe impact of their disease on their quality of life (QoL) (51.9%), work/daily activities (49.2%), emotional well-being (41.0%), personal relationships (26.0%), and close relatives’ life (32.3%); 30%–50% patients reported seldom/never being inquired about these aspects by their rheumatologists. Treatment attributes ranked as most important were the normalization of QoL (43.6%) and the relief from symptoms (35.2%). The satisfaction with their current antirheumatic therapy was high (>80% were “satisfied” or “very satisfied”), despite moderate/severe impact of disease. Conclusion: Patients with rheumatic diseases on SC biological therapy perceive a high disease impact on different aspects of daily life, despite being highly satisfied with their treatment; the perception is that physicians do not frequently address personal problems. Normalization of QoL is the most important attribute of therapies to patients. Keywords: rheumatic diseases, quality of life, emotional well-being, biological drugs, patient’s satisfaction

Perceptions of patients with rheumatic diseases on the impact on daily life and satisfaction with their medications: RHEU-LIFE, a survey to patients treated with subcutaneous biological products [Corrigendum] González CM, Carmona L, de Toro J, et al. Patient Prefer Adherence. 2017;11:1243–1252.On page 1245, Results; Response rate and sample description section, the second sentence “The mean age of the respondents was 41.7 years (SD 13.1), and 57.6% of them were females” should read “The mean age of the respondents was 51.7 years (SD 13.1), and 57.6% of them were females”.Read the original article

We report on a comparative study of the exchange bias effect and magnetic properties of Ni-NiO nanoparticulate systems synthesized by the chemical reduction of NiCl2 solution of two different molar concentrations--1M (high) and 0.05M (low)--followed by annealing of the dried precipitate in the temperature range 400-600 °C in air. Interestingly, the samples derived from the low molarity solution have higher Ni content and larger crystallite size than those prepared from their high molarity counterparts. These molarity dependent features subsequently modulate the magnitude of the exchange bias field in the samples, which is found to be absent or small in the 0.05M series, but of moderate value in the 1M samples. The different physical attributes of the particles derived from different concentrations of Ni-precursor solution are explained by invoking different nucleation kinetics and supersaturation degrees surrounding the viable growing nucleus. Furthermore, an observed increase of exchange bias with increasing annealing temperature, in contrast to the reported agglomeration of particles on annealing and subsequent reduction in bias magnitude, has been explained in correlation to the Ni-NiO interface density. [ABSTRACT FROM AUTHOR]

We report magnetic and exchange bias studies on Ni-NiO nanoparticulate systems synthesized by a two-step process, namely, chemical reduction of a Ni salt followed by air annealing of the dried precipitate in the temperature range 400-550 °C. Size of Ni and NiO crystallites as estimated from X-ray diffraction line broadening ranges between 10.5-13.5 nm and 2.3-4 nm, respectively. The magneto-thermal plots (M-T) of these bi-magnetic samples show a well developed peak in the vicinity of 130K. This has been identified as the superparamagnetic blocking temperature "TB" of NiO. Interestingly, all samples exhibit exchange bias even above their respective NiO blocking temperatures, right up to 300K, the maximum temperature of measurement. This is in contrast to previous reports since exchange bias requires the antiferromagnetic NiO to have a stable direction of its moment in order to pin the ferromagnet (Ni) magnetization, whereas such stability is unlikely above TB since the NiO is superparamagnetic, its moment flipping under thermal activation. Our observation is elucidated by taking into account the core-shell morphology of the Ni-NiO nanoparticles whereby clustering of some of these nanoparticles connects their NiO shells to form extended continuous regions of NiO, which because of their large size remain blocked at T > TB, with thermally stable spins capable of pinning the Ni cores and giving rise to exchange bias. The investigated samples may thus be envisaged as being constituted of both isolated core-shell Ni-NiO nanoparticles as well as clustered ones, with TB denoting the blocking temperature of the NiO shell of the isolated particles. [ABSTRACT FROM AUTHOR]

Exchange bias (EB) effects linked to surface spin freezing (SSF) are commonly found in iron oxide nanoparticles, while signatures of SSF in low-field temperature-dependent magnetization curves have been much less frequently reported. Here, we present magnetic properties of dense assemblies of similar-sized (∼8 nm diameter) particles synthesized by a magnetite (sample S1) and a maghemite (sample S2) method, and the influence of long-term (4 year) sample aging under ambient conditions on these properties. The size of the EB field of the different sample (fresh or aged) states is found to correlate with (a) whether a low-temperature hump feature signaling the SSF transition is detected in out-of-phase ac susceptibility or zero-field-cooled (ZFC) dc magnetization recorded at low field and with (b) the prominence of irreversibility between FC and ZFC curves recorded at high field. Sample S1 displays a lower magnetization than S2, and it is in S1 where the largest SSF effects are found. These effects are significantly weakened by aging but remain larger than the SSF effects in S2, where the influence of aging is considerably smaller. A non-saturating component due to spin disorder in S1 also weakens with aging, accompanied by, we infer, an increase in the superspin and the radius of the ordered nanoparticle cores. X-ray diffraction and Mössbauer spectroscopy provide indication of maghemite-like stoichiometry in both aged samples as well as thicker disordered particle shells in aged-S1 relative to aged-S2 (crystallographically-disordered and spin-disordered according to diffraction and Mössbauer, respectively). The pronounced diminution in SSF effects with aging in S1 is attributed to a (long-term) transition, caused by ambient oxidation, from magnetite-like to maghemite-like stoichiometry, and a concomitant softening of the spin-disordered shell anisotropy. We assess the impact of this anisotropy on the nature of the blocking of the nanoparticle superspins. [ABSTRACT FROM AUTHOR]

A comparative study of the structure and magnetic properties of Ni nanoparticles (20–80 nm) prepared by the chemical reduction of NiCl2 solution of four different concentrations is reported. The concentration of the NiCl2 solution has a profound influence on the room temperature (300 K) magnetic state of the resulting Ni nanoparticles, even though all four samples show the same x-ray diffraction (XRD) pattern, i.e., have the same crystal structure (tetragonal, as proposed by us). It is found that samples obtained from lower concentration solutions (0.1 and 0.5M) show a linear response with magnetic field while those obtained from higher concentration ones (1 and 2M) have a ferromagnetic component at 300 K. This difference in magnetic behavior has been attributed to the possible presence of fcc (face centered cubic) Ni cores in the particles of higher molarity samples, which therefore leads to strong interparticle dipolar interactions in them. The strong interactions, together with the magnetocrystalline anisotropy of the cores, present a significant barrier to the relaxation of core moments in these samples, giving rise to their blocked state even above 300 K, as evident from the irreversibility in the field cooled (FC) and zero field cooled (ZFC) curves, which starts right from the measuring temperature of 390 K. Intriguing features in the form of a sharp peak at 20 K and a hump at 12 K are observed in the ZFC curve of all samples, signaling magnetic transitions at these temperatures. Appreciably high magnetization values are also seen in the M-H plots at 5 K. The presence of these low temperature features irrespective of sample molarity indicates that the low temperature magnetic states of the samples, in contrast to their room temperature states, are independent of the concentration of the NiCl2 solution. [ABSTRACT FROM AUTHOR]

A nanogranular Co–CoO/Ag system (with core-shell/matrix structure), synthesized by reactive cosputtering, has been subjected to thermal treatments at progressively higher temperatures. The exchange-bias onset temperature increases in close correlation with the average superparamagnetic blocking temperature of the magnetic particles. This behavior, together with the nonmonotonic evolution of the exchange-bias field, is explained in terms of two structural relaxation processes previously characterized in simple Co/Ag granular alloys: (i) segregation of Co solute atoms from the Ag-rich matrix, and (ii) particle coarsening. [ABSTRACT FROM AUTHOR]

We present magnetic characterization of two series of samples grown by reactive sputtering of Co and Ag: (i) thin films obtained by cosputtering of these metals at different oxygen pressures, and (ii) Co/Ag multilayer films deposited with fixed Co layer thickness (1.1 nm) and oxygen pressure (2×10-5 mbar), and varying Ag layer thickness tAg. For certain preparation conditions the samples obtained with both synthesis methods consist of a dispersion of core-shell Co–CoO nanoparticles embedded in a Ag matrix. Regarding series (i), it is remarkable that the interesting core-shell/matrix structure, suggested by exchange-bias and giant magnetoresistance properties, could be achieved using the simple one-step technique of reactive cosputtering. In series (ii), the exchange-bias and coercivity fields strongly depend on the spacer layer thickness for tAg<4 nm, and then become roughly thickness independent. A discontinuous-continuous transition in the silver layers with increasing tAg, similar to that observed in a previous study, is hypothesized as the origin of the behavior in both fields. [ABSTRACT FROM AUTHOR]

The combination of Mössbauer spectroscopy and magnetization measurements is demonstrated to be efficient in the determination of the phases responsible for the glassy magnetic dynamics of the highly disordered alloy Fe[sub 35]Al[sub 50]B[sub 15] produced by mechanical alloying. Its spin-glass behavior is apparent from the FC-ZFC magnetization irreversibility, the thermoremanent magnetization, and the slightly frequency-dependent peak in the temperature dependence of the ac susceptibility. Furthermore, the maximum at T[sub p] ≈ 22 K in the real component of the ac susceptibility is accompanied by a sudden onset of the imaginary component. The fit of the frequency dependence of T[sub p] to the critical slowing down law yielded a critical exponent z v = 8 ± 1. However, Mössbauer spectroscopy uncovered the existence of two different Fe environments, of which only the minor one freezes at low temperatures into a distribution of magnetic sextets. This result, combined with the superparamagnetic behavior detected at moderate fields, allowed us to ascribe the spin glass behavior to the presence of interacting, very fine, ferromagnetic clusters (estimated size ∼ 1 nm). The origin of this nanoscale compositional heterogeneity is argued to be related to regions of partially unalloyed Fe. The conclusions are contrasted with other mechanically alloyed systems with reported spin glass behavior or compositional inhomogeneity. [ABSTRACT FROM AUTHOR]

We report the observation of spin-glass-like features in a Fe[sub 61]Re[sub 30]Cr[sub 9] sample obtained after high energy milling for 460 h. X-ray diffraction showed a broad nanocrystalline peak. The zero-field-cooled and field-cooled magnetization curves exhibited a clear irreversibility, the former showing a relatively sharp maximum for low fields at T[sub max]approx. 60 K. In addition, the temperature dependence of the magnetic AC susceptibility (χ[sub ac]) also showed a peak at approximately the same temperature. The frequency sensitivity of such maximum (p=ΔT[sub max]/T[sub max]Δ log wapprox. 0.02) is small compared to that of typical superparamagnets. However, we discuss the insufficiency of this set of phenomena to assert the existence of a true spin-glass transition and propose the blocking of interacting ferromagnetic nanoparticles as the origin of the observed behavior. The effect of annealing, rendered into nanocrystallite growth, on the χ[sub ac] maximum is studied in an attempt to test this explanation. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]