International Guillain-Barré Syndrome Outcome Study (IGOS): protocol of a prospective observational cohort study on clinical and biological predictors of disease course and outcome in Guillain-Barré syndrome

Guillain-Barré syndrome (GBS) is an acute polyradiculoneuropathy with a highly variable clinical presentation, course, and outcome. The factors that determine the clinical variation of GBS are poorly understood which complicates the care and treatment of individual patients. The protocol of the ongoing International GBS Outcome Study (IGOS), a prospective, observational, multi-centre cohort study that aims to identify the clinical and biological determinants and predictors of disease onset, subtype, course and outcome of GBS is presented here. Patients fulfilling the diagnostic criteria for GBS, regardless of age, disease severity, variant forms, or treatment, can participate if included within two weeks after onset of weakness. Information about demography, preceding infections, clinical features, diagnostic findings, treatment, course and outcome is collected. In addition, cerebrospinal fluid and serial blood samples for serum and DNA is collected at standard time points. The original aim was to include at least 1000 patients with a follow-up of 1-3 years. Data are collected via a web-based data entry system and stored anonymously. IGOS started in May 2012 and by January 2017 included more than 1400 participants from 143 active centres in 19 countries across 5 continents. The IGOS data/biobank is available for research projects conducted by expertise groups focusing on specific topics including epidemiology, diagnostic criteria, clinimetrics, electrophysiology, antecedent events, antibodies, genetics, prognostic modelling, treatment effects and long-term outcome of GBS. The IGOS will help to standardize the international collection of data and biosamples for future research of GBS. ClinicalTrials.gov Identifier: NCT01582763

Systematic investigation of the elastic proton-deuteron differential cross section at intermediate energies

To investigate the importance of three-nucleon forces (3NF) systematically over a broad range of intermediate energies, the differential cross sections of elastic proton-deuteron scattering have been measured at proton bombarding energies of 108, 120, 135, 150, 170 and 190 MeV at center-of-mass angles between $30^\circ$ and $170^\circ$. Comparisons with Faddeev calculations show unambiguously the shortcomings of calculations employing only two-body forces and the necessity of including 3NF. They also show the limitations of the latest few-nucleon calculations at backward angles, especially at higher beam energies. Some of these discrepancies could be partially due to relativistic effects. Data at lowest energy are also compared with a recent calculation based on \chipt

Trauma mechanism and patient reported outcome in tibial plateau fractures with posterior involvement

Introduction: Posterior tibial plateau fractures (PTPF) have a high impact on functional outcome and the optimal treatment strategy is not well established. The goal of this study was to assess the relationship between trauma mechanism, fracture morphology and functional outcome in a large multicenter cohort and define possible strategies to improve the outcome. Methods: An international retrospective cohort study was conducted in five level-1 trauma centers. All consecutive operatively treated PTPF were evaluated. Preoperative imaging was reviewed to determine the trauma mechanism. Patient reported outcome was scored using the Knee injury and Osteoarthritis Outcome Score (KOOS). Results: A total of 145 tibial plateau fractures with posterior involvement were selected with a median follow-up of 32.2 months (IQR 24.1-43.2). Nine patients (6%) sustained an isolated posterior fracture. Seventy-two patients (49%) sustained a two-column fracture and three-column fractures were diagnosed in 64 (44%) patients. Varus trauma was associated with poorer outcome on the 'symptoms' (p = 0.004) and 'pain' subscales (p = 0.039). Delayed-staged surgery was associated with worse outcome scores for all subscales except 'pain'. In total, 27 patients (18%) were treated with posterior plate osteosynthesis without any significant difference in outcome. Conclusions: Fracture morphology, varus trauma mechanism and delayed-staged surgery (i.e. extensive soft-tissue injury) were identified as important prognostic factors on postoperative outcome in PTPF. In order to assess possible improvement of outcome, future studies with routine preoperative MRI to assess associated ligamentous injury in tibial plateau fractures (especially for varus trauma) are needed. (c) 2021 Elsevier B.V. All rights reserved

Diffusive and ballistic current spin-polarization in magnetron-sputtered L1o-ordered epitaxial FePt

We report on the structural, magnetic, and electron transport properties of a L1o-ordered epitaxial iron-platinum alloy layer fabricated by magnetron-sputtering on a MgO(001) substrate. The film studied displayed a long range chemical order parameter of S~0.90, and hence has a very strong perpendicular magnetic anisotropy. In the diffusive electron transport regime, for temperatures ranging from 2 K to 258 K, we found hysteresis in the magnetoresistance mainly due to electron scattering from magnetic domain walls. At 2 K, we observed an overall domain wall magnetoresistance of about 0.5 %. By evaluating the spin current asymmetry alpha = sigma_up / sigma_down, we were able to estimate the diffusive spin current polarization. At all temperatures ranging from 2 K to 258 K, we found a diffusive spin current polarization of > 80%. To study the ballistic transport regime, we have performed point-contact Andreev-reflection measurements at 4.2 K. We obtained a value for the ballistic current spin polarization of ~42% (which compares very well with that of a polycrystalline thin film of elemental Fe). We attribute the discrepancy to a difference in the characteristic scattering times for oppositely spin-polarized electrons, such scattering times influencing the diffusive but not the ballistic current spin polarization.Comment: 22 pages, 13 figure

Does serous tubal intraepithelial carcinoma (STIC) metastasize?:The clonal relationship between STIC and subsequent high-grade serous carcinoma in BRCA1/2 mutation carriers several years after risk-reducing salpingo-oophorectomy

Objective: The majority of high-grade serous carcinomas (HGSC) of the ovary, fallopian tube, and peritoneum arise from the precursor lesion called serous tubal intraepithelial carcinoma (STIC). It has been postulated that cells from STICs exfoliate into the peritoneal cavity and give rise to peritoneal HGSC several years later. While co-existent STICs and HGSCs have been reported to share similarities in their mutational profiles, clonal relationship between temporally distant STICs and HGSCs have been infrequently studied and the natural history of STICs remains poorly understood. Methods: We performed focused searches in two national databases from the Netherlands and identified a series of BRCA1/2 germline pathogenic variant (GPV) carriers (n = 7) who had STIC, and no detectable invasive carcinoma, at the time of their risk-reducing salpingo-oophorectomy (RRSO), and later developed peritoneal HGSC. The clonal relationship between these STICs and HGSCs was investigated by comparing their genetic mutational profile by performing next-generation targeted sequencing. Results: Identical pathogenic mutations and loss of heterozygosity of TP53 were identified in the STICs and HGSCs of five of the seven patients (71%), confirming the clonal relationship of the lesions. Median interval for developing HGSC after RRSO was 59 months (range: 24–118 months). Conclusion: Our results indicate that cells from STIC can shed into the peritoneal cavity and give rise to HGSC after long lag periods in BRCA1/2 GPV carriers, and argues in favor of the hypothesis that STIC lesions may metastasize.</p

Does serous tubal intraepithelial carcinoma (STIC) metastasize?:The clonal relationship between STIC and subsequent high-grade serous carcinoma in BRCA1/2 mutation carriers several years after risk-reducing salpingo-oophorectomy

Objective: The majority of high-grade serous carcinomas (HGSC) of the ovary, fallopian tube, and peritoneum arise from the precursor lesion called serous tubal intraepithelial carcinoma (STIC). It has been postulated that cells from STICs exfoliate into the peritoneal cavity and give rise to peritoneal HGSC several years later. While co-existent STICs and HGSCs have been reported to share similarities in their mutational profiles, clonal relationship between temporally distant STICs and HGSCs have been infrequently studied and the natural history of STICs remains poorly understood. Methods: We performed focused searches in two national databases from the Netherlands and identified a series of BRCA1/2 germline pathogenic variant (GPV) carriers (n = 7) who had STIC, and no detectable invasive carcinoma, at the time of their risk-reducing salpingo-oophorectomy (RRSO), and later developed peritoneal HGSC. The clonal relationship between these STICs and HGSCs was investigated by comparing their genetic mutational profile by performing next-generation targeted sequencing. Results: Identical pathogenic mutations and loss of heterozygosity of TP53 were identified in the STICs and HGSCs of five of the seven patients (71%), confirming the clonal relationship of the lesions. Median interval for developing HGSC after RRSO was 59 months (range: 24–118 months). Conclusion: Our results indicate that cells from STIC can shed into the peritoneal cavity and give rise to HGSC after long lag periods in BRCA1/2 GPV carriers, and argues in favor of the hypothesis that STIC lesions may metastasize.</p

A new test of the construct validity of the CarerQol instrument: measuring the impact of informal care giving

Purpose: Most economic evaluations of health care programmes do not consider the effects of informal care, while this could lead to suboptimal policy decisions. This study investigates the construct validity of the CarerQol instrument, which measures and values carer effects, in a new population of informal caregivers. Methods: A questionnaire was distributed by mail (n = 1,100, net response rate = 21%) to regional informal care support centers throughout the Netherlands. Two types of construct validity, i.e., convergent and clinical validity, have been analyzed. Convergent validity was assessed with Spearman's correlation coefficients and multivariate correlation between the burden dimensions (CarerQol-7D) and the valuation component (CarerQol-VAS) of the CarerQol. Additionally, convergent validity was analyzed with Spearman's correlation coefficients between the CarerQol and other measures of subjective caregiver burden (SRB, PU). Clinical validity was evaluated with multivariate correlation between CarerQol-VAS and CarerQol-7D, characteristics of caregivers, care recipients and care situation among the whole sample of caregivers and subgroups. Results: The positive (negative) dimensions of CarerQol-7D were positively (negatively) related to CarerQol-VAS, and almost all had moderate strength of convergent validity. CarerQol-VAS was positively associated with PU and negatively with SRB. The CarerQol-VAS reflects differences in important background characteristics of informal care: type of relationship, age of the care recipient and duration of care giving were associated with higher CarerQol-VAS scores. These results confirmed earlier tests of the construct validity of the CarerQol. Furthermore, the dimensions of CarerQol-7D significantly explained differences in CarerQol-VAS scores among subgroups of carers. Conclusion: Notwithstanding the limitations of our study, such as the low response rate, this study shows that the CarerQol provides a valid means to measure carer effects for use in economic evaluations. Future research should derive a valuation set for the CarerQol and further address the instrument's content validity, sensitivity and reliability

Ferromagnetic Liquid Thin Films Under Applied Field

Theoretical calculations, computer simulations and experiments indicate the possible existence of a ferromagnetic liquid state, although definitive experimental evidence is lacking. Should such a state exist, demagnetization effects would force a nontrivial magnetization texture. Since liquid droplets are deformable, the droplet shape is coupled with the magnetization texture. In a thin-film geometry in zero applied field, the droplet has a circular shape and a rotating magnetization texture with a point vortex at the center. We calculate the elongation and magnetization texture of such ferromagnetic thin film liquid droplet confined between two parallel plates under a weak applied magnetic field. The vortex stretches into a domain wall and exchange forces break the reflection symmetry. This behavior contrasts qualitatively and quantitatively with the elongation of paramagnetic thin films.Comment: 10 pages, 4 figures, Submitted to Phys. Rev.

Measurement of the Gamow-Teller Strength Distribution in 58Co via the 58Ni(t,3He) reaction at 115 MeV/nucleon

Electron capture and beta decay play important roles in the evolution of pre-supernovae stars and their eventual core collapse. These rates are normally predicted through shell-model calculations. Experimentally determined strength distributions from charge-exchange reactions are needed to test modern shell-model calculations. We report on the measurement of the Gamow-Teller strength distribution in 58Co from the 58Ni(t,3He) reaction with a secondary triton beam of an intensity of ~10^6 pps at 115 MeV/nucleon and a resolution of \~250 keV. Previous measurements with the 58Ni(n,p) and the 58Ni(d,2He) reactions were inconsistent with each other. Our results support the latter. We also compare the results to predictions of large-scale shell model calculations using the KB3G and GXPF1 interactions and investigate the impact of differences between the various experiments and theories in terms of the weak rates in the stellar environment. Finally, the systematic uncertainties in the normalization of the strength distribution extracted from 58Ni(3He,t) are described and turn out to be non-negligible due to large interferences between the dL=0, dS=1 Gamow-Teller amplitude and the dL=2, dS=1 amplitude.Comment: 14 pages, 8 figure