Intersectionality and public understandings of health inequity in England: learning from the views and experiences of young adults

OBJECTIVES

Attempts to reduce health inequities in England frequently prioritise some equity dimensions over others. Intersectionality highlights how different dimensions of inequity interconnect and are underpinned by historic and institutionalised power imbalances. We aimed to explore whether intersectionality could help us shed light on young adults' understanding of health inequities.

STUDY DESIGN

The study incorporatedqualitative thematic analysis of primary data.

METHODS

Online focus groups with young adults (n = 25) aged 18-30 living in three English regions (Greater London; South Yorkshire/Midlands; North-East England) between July 2020 and March 2021. Online semistructured interviews (n = 2) and text-based communication was conducted for participants unable to attend online groups.

RESULTS

Young adults described experiencing discrimination, privilege, and power imbalances driving health inequity and suggested ways to address this. Forms of inequity included cumulative, within group, interacting, and the experience of privilege alongside marginalisation. Young adults described discrimination occurring in settings relevant to social determinants of health and said it adversely affected health and well-being.

CONCLUSION

Intersectionality, with its focus on discrimination and identity, can help public health stakeholders engage with young adults on health equity. An upstream approach to improving health equity should consider multiple and intersecting forms of discrimination along with their cultural and institutional drivers.

An automated algorithm minimising ATP failure: re-initiation to enhance anti-tachycardia pacing efficacy

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Medical Research Council, UK

Background

Re-initiation is an important mechanism of anti-tachycardia pacing (ATP) failure, whereby VT is first terminated by the initial ATP application, before being re-initiated by successive pulses. Current ICD designs are able to measure and store electrograms (EGMs) for detecting and classifying arrhythmias, which contain information that may also be used during ATP application. Developing an algorithm that automatically processes EGMs during ATP, with the goal of detecting the initial VT termination and truncating subsequent ATP pulses (which has the potential to re-initiate), may thus increase ATP efficacy.

Purpose

To develop a proof-of-concept ATP detection algorithm: Early Termination Detection Algorithm (ETDA), to automatically sense the signs of early VT termination and cease further ATP pulses based on real-time sensed EGMs from implanted devices.

Methods

A cohort of 7 porcine infarcted ventricular computational models were subject to virtual induction protocols to induce sustained VTs. Functional model properties were adjusted to provide 73 unique VT episodes (260≤VT cycle length (CL)≤480ms). For each episode, burst ATP was delivered from typical pacing sites near the right ventricle (RV) septum to evaluate its efficacy. The ATP failures and their failure mechanisms were identified, accordingly. During ATP application, five common sensing EGM vectors from implanted devices were recovered from simulations including can-to-Superior vena cava (SVC) coil, can-to-RV ring, SVC coil-to-RV coil ring, RV coil tip-to-RV coil ring and LV coil at the lateral base-to-RV tip. Our proposed ETDA utilises those EGMs for VT termination detection. Specifically, correlation coefficients (CCs) of the EGMs between two successive ATP pulses were calculated and averaged to identify sudden changes in EGM morphology that indicate VT termination (Fig A). A discriminating threshold on the CCs was chosen by comparing all re-initiation cases with detailed analysis of the actual VT termination time observed from simulation results. ETDA was then applied to all cases to identify initial termination and improvement in efficacy.

Results

Before ETDA application, ATP terminated 42 cases (58%, Fig C), with re-initiation attributing to 11 (35%) of ATP failures. Application of ETDA accurately detected VT termination in 91% of re-initiated cases, 90% of terminated cases and 81% of not-terminated cases (Fig B), which enhanced the overall ATP efficacy to 71% (P=0.08) (Fig C).

Conclusions

The real-time EGMs measured from standard ICD/CRT-D devices may be used to improve ATP efficacy through an approach such as ETDA. ETDA detects signs of early termination automatically in real time which enables identification of successful VT termination, truncating subsequent pulses that may re-initiate the VT, which enhances overall ATP efficacy.

In silico study of anti-tachycardia pacing efficacy optimisation through scar-targeted stimulation

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Medical Research Council, UK

Background

Anti-tachycardia pacing (ATP) is a reliable electrotherapy to painlessly terminate ventricular tachycardia (VT). However, ATP is often ineffective, particularly for fast VTs, which is often due to the inability of paced wavefronts to reach the re-entrant circuit, because of functional or anatomical barriers. It is thought that efficacy may be enhanced by optimised delivery closer to the re-entrant circuit driving the VT.

Purpose

To quantitatively assess the dependence of ATP efficacy upon different delivery locations with respect to the re-entrant circuit.

Methods

A cohort of 7 porcine ventricular infarct computational models were generated based on in vivo magnetic resonance imaging. Rapid-pacing protocols were applied to the cohort to induce VTs. Functional model parameters were adjusted to produce 73 episodes of sustained monomorphic VT, including 32 fast VTs (cycle length (CL)≤320ms) and 41 slow VTs (320ms-<VTCL≤<VTCL≤>480ms). Burst ATP (2 sequences of 8 pulses at 88% of VTCL) was separately delivered from 3 locations proximal to the re-entrant circuit (along the RV septum), specifically within the critical isthmus (CI), and at the Exit and Entrance sites, along with 3 locations distal to the circuit (lateral/posterior LV), based on multipolar implanted devices with LV epicardial leads, constituting 438 virtual scenarios and efficacy compared (Fig A).

Results

ATP efficacy was significantly higher for slow VTs than for fast VTs (65% vs 46%, P=0.00004) (Fig B). Separate analysis of slow VT cases revealed that delivering from distal locations to the re-entrant circuit was significantly more effective than delivering from proximal locations (72% vs 59%, P=0.04). However, for fast VT cases, the trend was reversed with proximal application (41%) being more effective than distal application (51%, P=0.15) (Fig B). Moreover, individual analysis on specific proximal locations revealed that in slow VT cases, delivering at the Exit site of VT was significantly less efficient than delivering at the Entrance site (46% vs 73%, P=0.01), with a similar (although non-significant) trend also being seen for fast VTs (44% vs 53%, P=0.5) (Fig C). Moreover, for fast VT cases, ATP delivery within the CI was overall the most effective (56%) than all other locations while this trend was not seen in slow VT cases.

Conclusions

ATP delivery proximal to the re-entrant circuit improves efficacy in fast VTs, but less so in slow VTs, where delivering from distal sites is superior. Specifically, for fast VTs, ATP delivery within the CI is the most effective. This work suggests that real-time alteration in applied ATP delivery site choice in a multipolar device (guided by the sensed VT rate by the device prior to therapy delivery) may be beneficial. Combined with the state-of-art leadless pacing technology, this also provides a clinical opportunity for patient-specific ATP delivery configuration and programming.

In-silico optimisation of ICD defibrillation efficacy by modifying lead/can configurations using a cohort of high-resolution whole-torso heart models

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Medical Research Council, UK

Background

ICD is an effective direct therapy against VT/VF by applying a strong electrical shock across the heart between the shocking coil and can. Conventionally, patients will have a shocking coil inside the right ventricle (RV) and a can at the upper left chest. However, due to infections or other conditions, the can may need to place towards the right chest. The placement of the RV coil may also vary in different cases, for example avoiding scar. However, it is unclear how defibrillation efficacy may be altered by these unavoidable modifications to conventional lead/can configurations and whether optimisation may be possible.

Purpose

To compare defibrillation efficacy of modifications of ICD configurations in a cohort of whole-torso models.

Methods

A cohort of 15 whole torso models was generated from high resolution CT data and contrast CT cardiac scans, including 5 dilated cardiomyopathy (DCM), 5 hypertrophic cardiomyopathy (HCM) and 5 structurally normal patients (Fig A). Transvenous ICDs were represented by a shocking coil inside the RV (near apex) and a (ground) can at the upper left chest as default settings. Configurations were then varied by moving the can to the right chest, moving the RV coil up the mid-septum or adding extra grounds (Superior Vena Cava (SVC) coil, coronary sinus (CS) coil (Fig A)). Defibrillation-strength shocks were applied to all models (Fig B). DFTs and mean electrical field were evaluated across the whole heart as well as specific LV, RV, RV insertion regions, along with overall impedance.

Results

Shifting the can from left to right significantly increased DFT for the whole heart (23 J vs 15 J, P=0.03) and LV (25 J vs 17 J, P=0.03) (Fig C) and reduced the mean electrical field. Moving the RV coil further up the septum did not significantly alter DFT (Fig D), but did reduce mean electrical field for all regions and reduce impedance significantly. Additional separate coils significantly reduced DFT for all regions (Fig D) by increasing mean electrical field, whilst adding both coils significantly reduced DFT the most (whole heart: 15 J vs 6 J, P=0.03) (Fig E). Impedance was increased significantly by adding SVC coil, but reduced significantly by adding CS coil. Adding both coils increased impedance slightly.

Conclusions

Although a right-sided can increases DFT by over 50%, additional leads (grounds) may mitigate this increase by increasing mean electrical field. Moving the RV coil closer to the mid-septum reduces DFT slightly, but also reduces mean electrical field and impedance significantly.

Perpendicularly magnetized Co/Pd-based magneto-resistive heterostructures on flexible substrates

Flexible magneto-resistive heterostructures have received a great deal of attention over the past few years as they allow for new product paradigms that are not possible with conventional rigid substrates. While the progress and development of systems with longitudinal magnetic anisotropy on non-planar substrates has been remarkable, flexible magneto-resistive heterostructures with perpendicular magnetic anisotropy (PMA) have never been studied despite the possibility to obtain additional functionality and improved performance. To fill this gap, flexible PMA Co/Pd-based giant magneto-resistive (GMR) spin-valve stacks were prepared by using an innovative transfer-and-bonding strategy exploiting the low adhesion of a gold underlayer to SiO _x /Si(100) substrates. The approach allows overcoming the limits of the direct deposition on commonly used polymer substrates, whose high surface roughness and low melting temperature could hinder the growth of complex heterostructures with perpendicular magnetic anisotropy. The obtained PMA flexible spin-valves show a sizeable GMR ratio (∼1.5%), which is not affected by the transfer process, and a high robustness against bending as indicated by the slight change of the magneto-resistive properties upon bending, thus allowing for their integration on curved surfaces and the development of a novel class of advanced devices based on flexible magneto-resistive structures with perpendicular magnetic anisotropy. Besides endowing the family of flexible electronics with PMA magneto-resistive heterostructures, the exploitation of the results might apply to high temperature growth processes and to the fabrication of other functional and flexible multilayer materials engineered at the nanoscale.

Epilepsy with auditory features: Contribution of known genes in 112 patients

Epilepsy with Auditory Features (EAF) is a focal epilepsy syndrome mainly of unknown aetiology. LGI1 and RELN have been identified as the main cause of Autosomal Dominant EAF and anecdotally reported in non-familial cases. Pathogenic variants in SCN1A and DEPDC5 have also been described in a few EAF probands belonging to families with heterogeneous phenotypes and incomplete penetrance. We aimed to estimate the contribution of these genes to the disorder by evaluating the largest cohort of EAF. We included 112 unrelated EAF cases (male/female: 52/60) who underwent genetic analysis by next-generation sequencing (NGS) techniques. Thirty-three (29.5%) were familial cases. We identified a genetic diagnosis for 8% of our cohort, including pathogenic/likely pathogenic variants (4/8 novel) in LGI1 (2.7%, CI: 0.6-7.6); RELN (1.8%; CI: 0.2-6.3); SCN1A (2.7%; CI: 0.6-7.6) and DEPDC5 (0.9%; CI 0-4.9).This study shows that the contribution of each of the known genes to the overall disorder is limited and that the genetic background of EAF is still largely unknown. Our data emphasize the genetic heterogeneity of EAF and will inform the diagnosis and management of individuals with this disorder.

First-phase ejection fraction predicts response to cardiac resynchronization therapy and adverse outcomes

Background

Cardiac Resynchronization Therapy (CRT) is an important therapeutic treatment for chronic heart failure. However, even in carefully selected cases up to 40% of patient fail to respond. First-phase ejection fraction (EF1), the ejection fraction up to the time of maximal ventricular contraction, is a novel and more sensitive echocardiographic measure of early systolic function.

Purpose

We examined the value of EF1, to predict response to CRT and clinical outcomes after CRT.

Methods

We analysed echocardiograms from 197 patients who underwent CRT between 2009 and 2018 and were followed to determine clinical outcomes.

Results

Volumetric response rate (reduction in end-systolic volume ≥15%) was 92.3% vs. 12.1%, for those with EF1 in the highest vs. lowest tertiles (p<0.001). A cut-off value of 11.9% for EF1 had >85% sensitivity and specificity for prediction of response to CRT; on multivariate logistic regression analysis incorporating previously defined predictors, EF1 was the strongest predictor of response (OR: 1.563, 95% CI: 1.371–1.782, p<0.001) (table 1). EF1 was also the strongest predictor of a clinical composite score (OR: 1.115, 95% CI: 1.044–1.191, p=0.001). Improvement in EF1 at 6 months after CRT implantation (6.5±5.8% vs 1.8±4.3% in responders vs. non-responders, p<0.001) was the best predictor of heart failure re-hospitalization and death after median follow-up of 29.2 months (HR: 0.819, 95% CI:0.765–0.876, p<0.001).

Conclusion

EF1 is a promising marker to identify patients likely to respond to CRT and most likely provides a measure of myocardial viability that determines response.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): British Heart Foundation, Wellcome/EPSRC Centre for Medical Engineering

Stress levels among workers: an observational study

Introduction

While some stress is a common part of everyday work for most people, higher or prolonged levels of stress might be harmful. Work-related stress is becoming a study subject because of its important implications: it is related to coronary heart disease and health in general and it also influences employee satisfaction and productivity. Because of this, workers should be aware of their stress levels in order to prevent disease and increase performance levels. Therefore, the aim of our study was to evaluate stress levels among employees.

Methods

We conducted an observational study in collaboration with Anteo, an onlus society based in Biella which employs more than 1000 workers. The first step of our study ran from December 2019 to February 2020, and included 300 workers. Informed consent was gathered trough structure chiefs prior to the intervention. We administered an online questionnaire based on the Kessler Psychological Distress Scale (K10) for screening than, subjects with a high perceived stress level were invited for a personal interview with our medical and psychological staff.

Results

The response rate was 31% with 94 questionnaires completed by the end of February 2020. 80% of respondents were women (75 out of 94). 17% of the employees presented a moderate to high level of stress (16 total, 72% women). Only 5% of workers presented a high level of stress (4 total, 50% women). All Patients presenting a high level of perceived stress went through medical and psychological evaluation, which confirmed the results in 88% cases (14 out of 16).

Conclusions

Our study evidenced that workers are often exposed to high levels of stress, which can influence health, everyday life as well as productivity. The introduction of stress management programs in companies could improve workers health and productivity having a positive impact on one's health, company productivity and society in general.

Key messages

The introduction of stress management programs might improve workers health and productivity. The introduction of stress management programs might have a positive impact on one’s health, company productivity and society in general.

The Netherlands

Background

While the literature on the relationship between populist radical right (PRR) parties and public health is still relatively scarce, early evidence suggests that PRR parties and their exclusionary policy agenda could be a threat to population health and health equity. The aim of this case study is to take a closer look at the standpoints and influence of the Dutch Party for Freedom (PVV) on national health and healthcare policies. The PVV is considered the main PRR party in the Netherlands and has been part of the 2010-2012 center-right coalition government.

Methods

This case study was informed by various information sources including academic literature, publicly available data, party manifestos and other statements issued by the PVV, coalition agreements, newspaper articles and interviews.

Results

Two key characteristics of PRR parties can be identified in relation to the PVV's standpoints on health and healthcare: authoritarianism (believing in the value of obeying and valuing authority) and nativism (believing that there is an ethnically united people with a territory). This is, for example, exemplified through strong support for the expansion of home and elderly care, while simultaneously opposing free, non-acute healthcare for refugees and asylum seekers who have not (yet) financially contributed to the healthcare system.

Conclusions

Health and healthcare are generally not priority issues for the PVV, whose political agenda tends to focus on immigration and law and order. While the party takes a leftist position on some aspects of the healthcare system, a nativist rhetoric remains present.

Defensive practices among non-medical health professionals: An overview of the scientific literature

INTRODUCTION

Defensive medicine (DM) is used when a doctor deviates from good practices to prevent complaints from patients or caregivers. This is a structured phenomenon that may not only affect the physician, but all healthcare personnel. The aim of this review was to determine whether DM is also performed by Non-Medical Health Professionals (NMHP), and the reasons, features, and effects of NMHP-DM.

MATERIALS AND METHODS

The review was conducted according to PRISMA guidelines, and specific inclusion criteria were used to search for relevant documents published up to 12 April 2018 in the main biomedical databases.

RESULTS

A total of 91 potentially relevant studies were identified. After the removal of duplicates, 72 studies were screened for eligibility, separately by two of the authors. Finally, 14 qualitative and quantitative studies were considered relevant for the purpose of the present review. These last studies were assessed for their methodological quality.

CONCLUSIONS

NMHP-DM is quite similar to DM practiced by doctors, and is mainly caused by fear of litigation. Midwives and nursing personnel practiced both active and passive DM, such as over-investigation, over-treatment, and avoidance of high-risk patients. NMHP-DM could increase risks for patient health, costs, risk of burnout for healthcare employees. Further studies are needed to better understand prevalence and features of NMHP-DM in all health professional fields, in order to apply appropriate preventive strategies to contrast DM among health care personnel.

Finite magnetic relaxation in x-space magnetic particle imaging: Comparison of measurements and ferrohydrodynamic models

Magnetic Particle Imaging (MPI) is an emerging tomographic imaging technology that detects magnetic nanoparticle tracers by exploiting their non-linear magnetization properties. In order to predict the behavior of nanoparticles in an imager, it is possible to use a non-imaging MPI relaxometer or spectrometer to characterize the behavior of nanoparticles in a controlled setting. In this paper we explore the use of ferrohydrodynamic magnetization equations for predicting the response of particles in an MPI relaxometer. These include a magnetization equation developed by Shliomis (Sh) which has a constant relaxation time and a magnetization equation which uses a field-dependent relaxation time developed by Martsenyuk, Raikher and Shliomis (MRSh). We compare the predictions from these models with measurements and with the predictions based on the Langevin function that assumes instantaneous magnetization response of the nanoparticles. The results show good qualitative and quantitative agreement between the ferrohydrodynamic models and the measurements without the use of fitting parameters and provide further evidence of the potential of ferrohydrodynamic modeling in MPI.

The determinants of defensive medicine in Italian hospitals: The impact of being a second victim

BACKGROUND

Defensive medicine affects healthcare systems worldwide. The concerns and perception about medical liability could lead practitioners to practise defensive medicine. Second victim is a healthcare worker involved in an unanticipated adverse patient event. The role of being second victim and the other possible determinants for defensive medicine is mostly unclear.

OBJECTIVE

To study the condition of being second victim as a possible determinants of defensive medicine among Italian hospital physicians.

DESIGN, SETTING AND PARTICIPANTS

A secondary analysis of the database of the national survey study on the prevalence and the costs of defensive medicine in Italy that was carried out between April 2014 and June 2014 in 55 Italian hospitals was performed for this study. The demographic section of the questionnaire was selected including the physician's age, gender, specialty, activity volume, grade and the variable being a second victim after an adverse event.

RESULTS

A total sample of 1313 physicians (87.5% response rate) was used in the data analyses. Characteristics of the participants included a mean age 49.2 of years and 19.4 average years of experience. The most prominent predictor for practising defensive medicine was the physicians' experience of being a second victim after an adverse event (OR=1.88; 95%CI, 1.38-2.57). Other determinants included age, years of experience, activity volume and risk of specialty.

CONCLUSIONS

Malpractice reform, effective support to second victims in hospitals together with a systematic use of evidence-based clinical guidelines, emerged as possible recommendations for reducing defensive medicine.

Electric field control of magnetic properties and electron transport in BaTiO₃-based multiferroic heterostructures

In this paper, we report on a purely electric mechanism for achieving the electric control of the interfacial spin polarization and magnetoresistance in multiferroic tunneling junctions. We investigate micrometric devices based on the Co/Fe/BaTiO3/La0.7Sr0.3MnO3 heterostructure, where Co/Fe and La0.7Sr0.3MnO3 are the magnetic electrodes and BaTiO3 acts both as a ferroelectric element and tunneling barrier. We show that, at 20 K, devices with a 2 nm thick BaTiO3 barrier present both tunneling electroresistance (TER = 12   ±   0.1%) and tunneling magnetoresistance (TMR). The latter depends on the direction of the BaTiO3 polarization, displaying a sizable change of the TMR from  -0.32   ±   0.05% for the polarization pointing towards Fe, to  -0.12   ±   0.05% for the opposite direction. This is consistent with the on-off switching of the Fe magnetization at the Fe/BaTiO3 interface, driven by the BaTiO3 polarization, we have previously demonstrated in x-ray magnetic circular dichroism experiments.

GLYOXALASE I A111E, PARAOXONASE 1 Q192R AND L55M POLYMORPHISMS IN ITALIAN PATIENTS WITH SPORADIC CEREBRAL CAVERNOUS MALFORMATIONS: A PILOT STUDY

It is already known that the conditions of increased oxidative stress are associated to a greater susceptibility to vascular malformations including cerebral cavernous malformations (CCMs). These are vascular lesions of the CNS characterized by abnormally enlarged capillary cavities that can occur sporadically or as a familial autosomal dominant condition with incomplete penetrance and variable clinical expression attributable to mutations in three different genes: CCM1(Krit1), CCM2 (MGC4607) and CCM3 (PDCD10). Polymorphisms in the genes encoding for enzymes involved in the antioxidant systems such as glyoxalase I (GLO I) and paraoxonase I (PON I) could influence individual susceptibility to the vascular malformations. A single nucleotide polymorphism was identified in the exon 4 of GLO 1 gene that causes an amino acid substitution of Ala for Glu (Ala111Glu). Two common polymorphisms have been described in the coding region of PON1, which lead to glutamine → arginine substitution at 192 (Q192R) and a leucine → methionine substitution at 55 (L55M). The polymorphisms were characterized in 59 patients without mutations in the CCM genes versus 213 healthy controls by PCR/RFLP methods using DNA from lymphocytes. We found that the frequency of patients carrying the GLO1 A/E genotype among the case group (56%) was four-fold higher than among the controls (14.1%). In the cohort of CCM patients, an increase in the frequency of PON192 Q/R genotype was observed (39% in the CCM group versus 3.7% in the healthy controls). Similarly, an increase was observed in the proportion of individuals with the genotype R/R in the disease group (5%) in respect to the normal healthy cohort (0.5%). Finally, the frequency of the PON55 heterozygotes L/M genotype was 29% in patients with CCMs and 4% in the healthy controls. The same trend was observed in PON55 homozygous M/M genotype frequency (CCMs 20% vs controls 10%). The present study aimed to investigate the possible association of GLO1 A111E, PON1 Q192R and L55M polymorphisms with the risk of CCMs. We found that individuals with the GLO1 A /E genotype, PON192/QR-RR genotypes and PON55/LM-MM genotypes had a significantly higher risk of CCMs compared with the other genotypes. However, because CCM is a heterogeneous disease, other additional factors might be involved in the initiation and progression of CCM disease.

Recent progress in ferrofluids research: novel applications of magnetically controllable and tunable fluids

Ferrofluids are suspensions of magnetic nanoparticles that have the attractive feature of being controlled by applied magnetic fields. Ferrofluids have been studied for decades in an ever growing number of applications that take advantage of their response to applied magnetic fields. Here, we provide a summary of recent advances in established and emerging applications of ferrofluids, including applications in optics, sensors, actuators, seals, lubrication, and static/dynamic magnetically driven assembly of structures.

Electric control of magnetism at the Fe/BaTiO₃ interface

Interfacial magnetoelectric coupling is a viable path to achieve electrical writing of magnetic information in spintronic devices. For the prototypical Fe/BaTiO₃ system, only tiny changes of the interfacial Fe magnetic moment upon reversal of the BaTiO₃ dielectric polarization have been predicted so far. Here, by using X-ray magnetic circular dichroism in combination with high resolution electron microscopy and first principles calculations, we report on an undisclosed physical mechanism for interfacial magnetoelectric coupling in the Fe/BaTiO₃ system. At this interface, an ultrathin oxidized iron layer exists, whose magnetization can be electrically and reversibly switched on-off at room-temperature by reversing the BaTiO₃ polarization. The suppression / recovery of interfacial ferromagnetism results from the asymmetric effect that ionic displacements in BaTiO₃ produces on the exchange coupling constants in the interfacial oxidized Fe layer. The observed giant magnetoelectric response holds potential for optimizing interfacial magnetoelectric coupling in view of efficient, low-power spintronic devices.

Obtaining the structure factors for an epitaxial film using Cu X-ray radiation

Determining atomic positions in thin films by X-ray diffraction is, at present, a task reserved for synchrotron facilities. Here an experimental method is presented which enables the determination of the structure factor amplitudes of thin films using laboratory-based equipment (Cu Kα radiation). This method was tested using an epitaxial 130 nm film of CuMnAs grown on top of a GaAs substrate, which unlike the orthorhombic bulk phase forms a crystal structure with tetragonal symmetry. From the set of structure factor moduli obtained by applying this method, the solution and refinement of the crystal structure of the film has been possible. The results are supported by consistent high-resolution scanning transmission electron microscopy and stoichiometry analyses.

Spinal and bulbar muscular atrophy: pathogenesis and clinical management

Spinal and bulbar muscular atrophy, or Kennedy's disease, is an X-linked motor neuron disease caused by polyglutamine repeat expansion in the androgen receptor. The disease is characterised by weakness, atrophy and fasciculations in the limb and bulbar muscles. Affected males may have signs of androgen insensitivity, such as gynaecomastia and reduced fertility. Neurophysiological studies are typically consistent with diffuse denervation atrophy, and serum creatine kinase is usually elevated 2-5 times above normal. Progression of the disease is slow, and the focus of spinal and bulbar muscular atrophy (SBMA) management is to prevent complications.

Prognostic factors and outcome of Epstein-Barr virus DNAemia in high-risk recipients of allogeneic stem cell transplantation treated with preemptive rituximab

AIMS AND METHODS

This study assessed incidence, predictive factors, and outcome of Epstein-Barr virus (EBV) DNAemia in 100 recipients of allogeneic hematopoietic stem cell transplant. A total of 68 patients received anti-thymocyte globulin before unrelated grafts.

RESULTS

Cumulative incidence of high-load EBV DNAemia defined by levels >10,000 copies/mL was 14% at 12 months. In multivariate analysis, a CD4+ T-lymphocyte count >50 μL at day +30 was the only factor significantly associated with a reduced risk of high-load EBV DNAemia. Thirteen of 16 patients with high viral loads were preemptively treated with rituximab and achieved EBV DNA negativity. Three patients had already developed post-transplant lymphoproliferative disorder (PTLD) at the time of detection of high EBV DNA loads, and they obtained complete response after rituximab infusions and chemotherapy. Patients with high EBV DNA load had a significantly higher transplant-related mortality (TRM) compared with patients with negative or low viral load (54% vs. 16%, P = 0.009) and a trend to lower overall survival (55% vs. 29%, P = 0.060).

CONCLUSION

We conclude that CD4+ cell count at day +30 is a predictive factor for EBV DNAemia and may help identify patients requiring closer monitoring. Although only 3% of patients progressed to PTLD and were all successfully managed, EBV reactivation was associated with higher TRM, mainly because of infections.

Clinical management of thyroid nodules with indeterminate cytology: our institutional experience using SIAPEC cytological criteria and V600-BRAF test

BACKGROUND

We evaluated the diagnostic accuracy of thyroid FNAC, integrated with V600E - BRAF mutational study. Herein, we report our experience using the SIAPEC cytological morphological criteria.

METHODS

From September 2009 to December 2010, we performed ultrasound-guided fine needle aspiration cytology (FNAC) on 124 patients with clinical evidence of a thyroid nodule, classifying the results in five cytological categories, according to Italian Society of Pathology and Cytology (SIAPEC) consensus conference morphological criteria. In patients with indeterminate (Tir3), suggestive of malignancy (Tir4) or positive for malignancy specimens (Tir5), we obtained a new biopsy in order to study V600E BRAF status. Patients with a diagnosis of Tir2 were assessed every six months with follow-up in the subsequent years. Patients with cytological diagnosis of Tir3, Tir4 and Tir5 underwent thyroid surgical resection with histological assessment of the lesion. Cyto-histological correlation was evaluated.

RESULTS

We obtained the following results: Tir2 = 103 (83.1%), Tir3 = 14 (11.3%), Tir4 = 2 (1.6%); Tir5 = 5 (4%). B-RAF mutation was found on 1 Tir3, 1 Tir4 and 2 Tir5. Thyroidectomy was performed on 17 patients classified as Tir3, Tir4 and Tir5. The diagnostic specificity of FNB was of 94.5%, a sensitivity of 100%, a predictive value positive for neoplasia of 77.7 % and a predictive value of malignancy of 61.7%.

CONCLUSIONS

Diagnostic accuracy of cytology can be improved through the study of mutational status of BRAF gene. These additional evaluations are well studied, easy to perform and could enter in the current diagnostic procedures to optimize clinical management of thyroid nodular disease.

All-nanoparticle concave diffraction grating fabricated by self-assembly onto magnetically-recorded templates

Using the enormous magnetic field gradients present near the surface of magnetic recording media, we assemble diffraction gratings with lines consisting entirely of self-assembled magnetic nanoparticles that are transferred to flexible polymer thin films. These nanomanufactured gratings have line spacings programmed with commercial magnetic recording and are inherently concave with radii of curvature controlled by varying the polymer film thickness. This manufacturing approach offers a low-cost alternative for realizing concave gratings and more complex optical materials assembled with single-nanometer precision.

Growth of ultrathin epitaxial Fe/MgO spin injector on (0, 0, 1) (Ga, Mn)As

We have grown an ultrathin epitaxial Fe/MgO bilayer on (Ga, Mn)As by e-beam evaporation in UHV. The system structure has been investigated by high resolution transmission electron microscopy (TEM) experiments which show that the Fe and MgO films, covering completely the (Ga, Mn)As, grow with the epitaxial relationship Fe[100](001) [parallel] MgO[110](001) [parallel] (Ga,Mn)As[110](001). The magnetic reversal process, studied by the magneto-optical Kerr effect (MOKE) at room temperature, demonstrates that the iron is ferromagnetic and possesses a cubic anisotropy, confirming the epitaxy relationship found with TEM. Resistivity measurements across the barrier display a non-Ohmic behavior characterized by cubic conductance as a function of the applied voltage suggesting tunneling-dominated transport across the barrier.

Efficacy and safety of peripheral blood stem cell mobilization and collection: a single-center experience in 190 allogeneic donors

BACKGROUND

In the past two decades peripheral blood stem cells (PBSCs) have increasingly replaced marrow as stem cells source for allogeneic transplantation. The PBSC donation initially applied only to related donors; later, due to the safety of the procedure, it was extended to unrelated donors.

STUDY DESIGN AND METHODS

We have retrospectively collected data regarding mobilization, collection, and short- and long-term follow-up of 190 consecutive donors, 174 related and 16 unrelated. All donors followed a standard protocol for mobilization and underwent at least one PBSC collection. Follow-up in related donors was performed every 4 months in the first year and then annually, with no time limits, while unrelated donors were monitored for 10 years.

RESULTS

All 190 donors completed the established mobilization protocol. The mobilizing capacity was significantly greater in males and in donors less than 60 years old. No case of major toxicity by granulocyte-colony-stimulating factor was found, nor thromboembolic events. The total dose of CD34+/recipient (median 5.8×10(6)/kg recipient/body weight) was statistically correlated with age, CD34+ before and after mobilization, and collection efficiency. Compliance to follow-up was 66%, with a significant difference between related and unrelated (63% vs. 100%, p=0.03). During follow-up no significant abnormalities in hematologic variables or hematologic malignancies were reported.

CONCLUSION

Our study allowed us to define the PBSC donation as "a safe procedure for the donors," with short- and long-term effects limited to a small percentage of donors and "effective for the recipient," due to the dose of collected CD34+, adequate for transplantation in almost all recipients.

Oscillatory shear response of dilute ferrofluids: predictions from rotational Brownian dynamics simulations and ferrohydrodynamics modeling

Ferrofluids are colloidal suspensions of magnetic nanoparticles that exhibit normal liquid behavior in the absence of magnetic fields but respond to imposed magnetic fields by changing their viscosity without loss of fluidity. The response of ferrofluids to constant shear and magnetic fields has received a lot of attention, but the response of ferrofluids to oscillatory shear remains largely unexplored. In the present work we used rotational Brownian dynamics to study the dynamic properties of ferrofluids with thermally blocked nanoparticles under oscillatory shear and constant magnetic fields. Comparisons between simulations and modeling using the ferrohydrodynamics equations were also made. Simulation results show that, for small rotational Péclet number, the in-phase and out-of-phase components of the complex viscosity depend on the magnitude of the magnetic field and frequency of the shear, following a Maxwell-like model with field-dependent viscosity and characteristic time equal to the field-dependent transverse magnetic relaxation time of the nanoparticles. Comparison between simulations and the numerical solution of the ferrohydrodynamic equations shows that the oscillatory rotational magnetoviscosity for an oscillating shear field obtained using the kinetic magnetization relaxation equation quantitatively agrees with simulations for a wide range of Péclet number and Langevin parameter but has quantitative deviations from the simulations at high values of the Langevin parameter. These predictions indicate an apparent elastic character to the rheology of these suspensions, even though we are considering the infinitely dilute limit in which there are negligible particle-particle interactions and, as such, chains do not form. Additionally, an asymptotic analytical solution of the ferrohydrodynamics equations, valid for Pe<<2, was used to demonstrate that the Cox-Merz rule applies for dilute ferrofluids under conditions of small shear rates. At higher shear rates the Cox-Merz rule ceases to apply.

The natural history of spinocerebellar ataxia type 1, 2, 3, and 6: a 2-year follow-up study

OBJECTIVE

To obtain quantitative data on the progression of the most common spinocerebellar ataxias (SCAs) and identify factors that influence their progression, we initiated the EUROSCA natural history study, a multicentric longitudinal cohort study of 526 patients with SCA1, SCA2, SCA3, or SCA6. We report the results of the 1- and 2-year follow-up visits.

METHODS

As the primary outcome measure we used the Scale for the Assessment and Rating of Ataxia (SARA, 0-40), and as a secondary measure the Inventory of Non-Ataxia Symptoms (INAS, 0-16) count.

RESULTS

The annual increase of the SARA score was greatest in SCA1 (2.18 ± 0.17, mean ± SE) followed by SCA3 (1.61 ± 0.12) and SCA2 (1.40 ± 0.11). SARA progression in SCA6 was slowest and nonlinear (first year: 0.35 ± 0.34, second year: 1.44 ± 0.34). Analysis of the INAS count yielded similar results. Larger expanded repeats and earlier age at onset were associated with faster SARA progression in SCA1 and SCA2. In SCA1, repeat length of the expanded allele had a similar effect on INAS progression. In SCA3, SARA progression was influenced by the disease duration at inclusion, and INAS progression was faster in females.

CONCLUSIONS

Our study gives a comprehensive quantitative account of disease progression in SCA1, SCA2, SCA3, and SCA6 and identifies factors that specifically affect disease progression.

Magnetoviscosity in dilute ferrofluids from rotational brownian dynamics simulations

Ferrofluids are suspensions of magnetic nanoparticles which respond to imposed magnetic fields by changing their viscosity without losing their fluidity. Prior work on modeling the behavior of ferrofluids has focused on using phenomenological suspension-scale continuum equations. A disadvantage of this approach is the controversy surrounding the equation describing the rate of change of the ferrofluid magnetization, the so-called magnetization relaxation equation. In this contribution the viscosity of dilute suspensions of spherical magnetic nanoparticles suspended in a Newtonian fluid and under applied shear and constant magnetic fields is studied through rotational brownian dynamics simulations. Simulation results are compared with the predictions of suspension-scale models based on three magnetization relaxation equations. Excellent agreement is observed between simulation results and the predictions of an equation due to Martsenyuk, Raikher, and Shliomis. Good qualitative agreement is observed with predictions of other equations, although these models fail to accurately predict the magnitude and shear rate dependence of the magnetic-field-dependent effective viscosity. Finally, simulation results over a wide range of conditions are collapsed into master curves using a Mason number defined based on the balance of hydrodynamic and magnetic torques.