bluuebunny/crossref_metadata_2025 huggingface dataset:
Gaining Community Entry with Survivors for Forensic Human Rights and Humanitarian Intervention
Authors: Kim Jaymelee , Elgerud Lucia , Tuller Hugh
Published: February 2022

As forensic humanitarian and forensic human rights anthropology has continued to evolve, an ongoing concern in the field is meaningful engagement with survivors and the imperative to do no harm. For forensic anthropologists attempting to engage in grassroots forensic intervention, unaffiliated with an international investigation, means for effectively accessing and engaging communities has not been widely discussed. Here, forensic anthropologists draw on multiple, cross-cultural contexts to discuss methods and techniques for introducing forensic partnerships to communities. To do this, the scientist must consider their positionality as well as that of the stakeholders, develop effective local relationships, and consider a community-grounded approach. This paper argues that drawing on broader cultural anthropological training, ultimately informs one’s ability to gain entry into at-risk and vulnerable communities while minimizing harm. To illustrate this point, examples are drawn from Canada, Uganda, Cyprus, and Somaliland.
Neuronal endolysosomal transport and lysosomal functionality in maintaining axonostasis
Authors: Roney Joseph C. , Cheng Xiu-Tang , Sheng Zu-Hang
Published: February 2022

Lysosomes serve as degradation hubs for the turnover of endocytic and autophagic cargos, which is essential for neuron function and survival. Deficits in lysosome function result in progressive neurodegeneration in most lysosomal storage disorders and contribute to the pathogenesis of aging-related neurodegenerative diseases. Given their size and highly polarized morphology, neurons face exceptional challenges in maintaining cellular homeostasis in regions far removed from the cell body where mature lysosomes are enriched. Neurons therefore require coordinated bidirectional intracellular transport to sustain efficient clearance capacity in distal axonal regions. Emerging lines of evidence have started to uncover mechanisms and signaling pathways regulating endolysosome transport and maturation to maintain axonal homeostasis, or “axonostasis,” that is relevant to a range of neurologic disorders. In this review, we discuss recent advances in how axonal endolysosomal trafficking, distribution, and lysosomal functionality support neuronal health and become disrupted in several neurodegenerative diseases.
Viscoelastic response of fluid trapped between two dissimilar van der Waals surfaces
Authors: Tendong E , Saha-Dasgupta T , Chakrabarti J
Published: February 2022

Employing grand canonical Monte-Carlo and molecular dynamics simulations, the viscoelastic response of trapped fluid under molecularly thin confinement by walls having different wall–fluid interaction strengths, is investigated. With increase in slit asymmetry, given by the ratio of interaction strengths of the wall having strong wall–fluid interaction to that of the wall with weak wall–fluid interaction, a crossover in effective density of the fluid film, from rarer (R) to denser (D) than the bulk density is observed. Upon increasing asymmetry further, the dense fluid (F) layers undergo bond-orientational (S) ordering. The variation of viscoelastic relaxation time with scaled asymmetry shows a universal behavior, independent of slit width, with two distinct regimes. Below a critical value of asymmetry, the viscoelastic relaxation time is a slowly varying function of asymmetry, comparable with the structural relaxation time. Beyond the critical asymmetry, on the other hand, viscoelastic response time shows a sharp increase upon increasing asymmetry, deviating markedly from the structural relaxation time. Interestingly the critical asymmetry value is found to correlate with R to D crossover. The microscopic origin of the two-regime universal behavior of viscoelastic response time is found to stem from the fact that below critical asymmetry, the overall viscoelastic behaviour of the slit is dominated by that of the fast relaxing layer close to the weakly attracting surface, while above the critical asymmetry, the relaxation behaviour is guided by the dense fluid layer adjacent to the strongly attracting wall. In vicinity of fluid to ordering transition, the loss and storage moduli merge for low frequencies as in gel-like mechanical behaviour. The storage modulus takes over the loss modulus in the phase co-existence region even before the long ranged order sets in. Our findings bear important implications for fluid transport in hetero-structured geometry in nanotechnology.
Localization phenomena and electronic transport in irradiated Aubry–André–Harper systems
Authors: Sarkar Manik , Maiti Santanu K , Dey Moumita
Published: February 2022

The role of light irradiation on electronic localization is critically investigated for the first time in a tight-binding lattice where site energies are modulated in the cosine form following the Aubry–André–Harper (AAH) model. The critical point of transition from delocalized-to-localized phase can be monitored selectively by regulating the light parameters that is extremely useful to have controlled electron transmission across the system. Starting with a strictly one-dimensional (1D) AAH chain, we extend our analysis considering a two-stranded ladder model which brings peculiar signatures in presence of irradiation. Unlike 1D system, AAH ladder exhibits a mixed phase (MP) zone where both extended and localized energy eigenstates co-exist. This is the fundamental requirement to have mobility edge in energy band spectrum. A mathematical description is given for decoupling the irradiated ladder into two effective 1D AAH chains. The underlying mechanism of getting a MP zone relies on the availability of two distinct critical points (CPs) of the decoupled chains, in presence of second-neighbor hopping between the two strands. Using a minimal coupling scheme the effect of light irradiation is incorporated following the Floquet–Bloch ansatz. The localization behaviors of different energy eigenstates are studied by calculating inverse participation ratio, and, are further explained in a more compact way by calculating two-terminal transmission probabilities together with average density of states. Finally, the decoupling procedure is extended for a more general multi-stranded AAH ladders where multiple CPs and thus multiple mobility edges are found. Our analysis may provide a new route of engineering localization properties in similar kind of other fascinating quasiperiodic systems.
A multi-institutional comparison of dosimetric data for a 0.35 T MR-linac
Authors: Khan Ahtesham Ullah , Lotey Rajiv , DeWerd Larry A , Yadav Poonam
Published: February 2022

Objective. A comparison of percent depth dose (PDD) curves, lateral beam profiles, output factors (OFs), multileaf collimator (MLC) leakage, and couch transmission factors was performed between ten institutes for a commercial 0.35 T MR-linac. Approach. The measured data was collected during acceptance testing of the MR-linac. The PDD curves were measured for the 3.32 × 3.32 cm2, 9.96 × 9.96 cm2, and 27.20 × 24.07 cm2 field sizes. The lateral beam profiles were acquired for a 27.20 × 24.07 cm2 field size using an ion chamber array and penumbra was defined as the distance between 80% of the maximum dose and 20% of the maximum dose after normalizing the profiles to the dose at the inflection points. The OFs were measured using solid-state dosimeters, whereas radiochromic films were utilized to measure radiation leakage through the MLC stacks. The relative couch transmission factors were measured for various gantry angles. The variation in the multi-institutional data was quantified using the percent standard deviation metric. Main results. Minimal variations (<1%) were found between the PDD data, except for the build-up region and the deeper regions of the PDD curve. The in-field region of the lateral beam profiles varied <1.5% between different institutions and a small variation (<0.7 mm) in penumbra was observed. A variation of <1% was observed in the OF data for field sizes above 1.66 × 1.66 cm2, whereas large variations were shown for small-field sizes. The average and maximum MLC leakage was calculated to be <0.3% and <0.6%, which was well below the international electrotechnical commission (IEC) leakage thresholds. The couch transmission was smallest for oblique beams and ranged from 0.83 to 0.87. Significance. The variation in the data was found to be relatively small and the different 0.35 T MR-linacs were concluded to have similar dosimetric characteristics.
Nature of ideal MHD instabilities as described by multi-region relaxed MHD
Authors: Kumar A , Nührenberg C , Qu Z , Hole M J , Doak J , Dewar R L , Hudson S R , Loizu J , Aleynikova K , Baillod A , Hezaveh H
Published: February 2022

In this work, the stepped pressure equilibrium code (SPEC) (Hudson et al 2012 Phys. Plasmas
19 112502), which computes the equilibria of the multi-region relaxed magnetohydrodynamic energy principle (MRxMHD), has been upgraded to determine the MRxMHD stability in toroidal geometry. A theoretical formalism for SPEC is obtained by relating the second variation of the MRxMHD energy functional to the Hessian matrix, enabling the prediction of magnetohydrodynamic (MHD) linear instabilities. Negative eigenvalues of this matrix imply instability. Further, we demonstrate our method on simplified test scenarios in both tokamak and stellarator magnetic topologies, with a systematic comparison study between the marginal stability prediction of the SPEC with the ideal MHD stability code packages CAS3D and MISHKA-1.
Modelling and theoretical understanding of the isotope effect from JET experiments in view of reliable predictions for deuterium-tritium plasmas
Authors: Garcia J , Casson F J , Bañón Navarro A , Bonanomi N , Citrin J , King D , Mantica P , Mariani A , Marin M , Mazzi S , Viezzer E
Published: February 2022

This is an overview of the theoretical understanding of the so-called isotope effect in JET hydrogen versus deuterium plasmas. Experimentally, weak to moderate deviations from naive GyroBohm scaling expectations are found for the core heat transport in L and H-modes. The physical mechanisms behind such deviations are analysed in the framework of the gyrokinetic theory. In the case of particle transport, isotope effects are mostly found in the plasma edge where the density is higher in deuterium than in hydrogen plasmas. In general, both the thermal energy and particle confinement increase with increasing main ion mass. A comparison of such results to expectations for deuterium-tritium plasmas in ITER is discussed.
Laser-based photonuclear production of medical isotopes and nuclear waste transmutation
Authors: Lobok M G , Brantov A V , Bychenkov V Yu
Published: February 2022

The results of complex simulations using PIC-GEANT4 (particle-in-cell and Monte-Carlo) codes based on the generation of a high-energy electron bunch by a short laser pulse propagating in a relativistic self-trapping regime in a near-critical plasma has been applied to assess the possibility of medical isotope production and nuclear waste transmutation. It has been demonstrated that a 10 Hz 30 fs 4 J laser pulse is well suited to the production of therapeutic amounts of several standard medical radionuclides (111In, 123I, 103Pd, 62Cu, 64Cu). The use of direct electron irradiation has an advantage over the use of bremsstrahlung gamma radiation from the converter due to the simplification of the production scheme without loss of radionuclide yield. The study of the transmutation of long-lived fusion products showed low efficiency and the need for preliminary isotope separation. Achieving as little as 10% reduction in the activity of a 10 g sample requires the continuous operation of the next-generation laser system at a high repetition rate (1 MHz–100 kHz) for (one to ten) years.
A grounded electrode beneath dielectric targets, including cancer cells, enhances the impact of cold atmospheric plasma jet
Authors: Schweigert Irina , Zakrevsky Dmitry , Milakhina Elena , Gugin Pavel , Biryukov Mikhail , Patrakova Ekaterina , Koval Olga
Published: February 2022

The effect of the presence or absence of a grounded substrate beneath dielectric targets, including cancer cells, during exposure to the cold atmospheric plasma jet is studied in the experiments and in fluid model simulations for the discharge parameters typical for the medical applications. It is shown that the dynamics of streamers generated in each positive cycle of ac voltage depends on the grounded substrate position. The streamers approach the target more often if the grounded substrate is beneath the target, that provides more intensive plasma-target interaction. In this case, the measured spectrum of plasma jet emission near the target demonstrates much higher intensity compared to an electrically isolated target case. The calculated and measured discharge currents with time demonstrate a mismatch of frequencies of the ac voltage and current over the target. The viability of A431 human skin carcinoma and MX7 mouse rhabdomyosarcoma cells treated by cold atmospheric plasma jet with/without the grounded substrate is measured with MTT assay 24 h after. The results show an enhanced suppression of the cell viability when using the grounded substrate for both cell lines. Achieving effective death of tumor cells with a shorter irradiation time can be considered an advantage of using a grounded electrode beneath the bio target.
Radiation reaction-dominated regime of wakefield acceleration
Authors: Golovanov A A , Nerush E N , Kostyukov I Yu
Published: February 2022

We study electron acceleration in a plasma wakefield under the influence of the radiation-reaction force caused by the transverse betatron oscillations of the electron in the wakefield. Both the classical and the strong quantum-electrodynamic (QED) limits of the continuous radiation reaction are considered. For the constant accelerating force, we show that the amplitude of the oscillations of the QED parameter χ in the radiation-dominated regime reaches an equilibrium value determined only by the magnitude of the accelerating field, while the averaged over betatron oscillations radiation reaction force saturates at a value smaller than the accelerating force and thus is incapable of stopping acceleration. We find the parameters of the electron bunch and the plasma accelerator for which reaching such a regime is possible. We also study effects of the dephasing and the corresponding change of the accelerating force over the course of acceleration and conclude that the radiation-dominated regime is realized both in cases of single-stage acceleration with slow dephasing (usually corresponding to bunch-driven plasma accelerators) and multi-stage acceleration with fast dephasing (corresponding to the use of laser-driven accelerators).
Structural and optical properties of BaTiO3 modified cadmium alkali borate glasses
Authors: Chandra Sekhar Kotagiri , Shareefuddin Md , El-Denglawey A. , Saddeek Yasser B
Published: February 2022

Borate glasses Na2B4O7 – CdO – CuO- BaTiO3 have been manufactured by the traditional melt quenching method. The increment of BaTiO3 affects strictly the density and the molar volume of the glass samples. The spectroscopic investigations by FTIR and Raman spectra show that the glass network consists of different structural units of [BO3] and [BO4] along with [TiO4]. The elaborated investigations assume the glass former role of TiO2. These arguments depend on the transformation of [BO3] into [BO4] units, which result in a decrement in the magnitude of disorder in the glass structure. The compositional dependence on BaTiO3 reveals that the behavior of Urbach energy confirms the decrement of disorder and the trend of the optical band gap shows a decrement process with a priority to direct transitions. Moreover, EPR spectra revealed that the Cu2+ ions occupy the positions of elongated octahedral positions with tetragonal distortions.
Nonequilibrium effects of reactive flow based on gas kinetic theory*
Authors: Su Xianli , Lin Chuandong
Published: February 2022

How to accurately probe chemically reactive flows with essential thermodynamic nonequilibrium effects is an open issue. Via the Chapman–Enskog analysis, the local nonequilibrium particle velocity distribution function is derived from the gas kinetic theory. It is demonstrated theoretically and numerically that the distribution function depends on the physical quantities and derivatives, and is independent of the chemical reactions directly as the chemical time scale is longer than the molecular relaxation time. Based on the simulation results of the discrete Boltzmann model, the departure between equilibrium and nonequilibrium distribution functions is obtained and analyzed around the detonation wave. In addition, it has been verified for the first time that the kinetic moments calculated by summations of the discrete distribution functions are close to those calculated by integrals of their original forms.
Up/down-conversion luminescence of monoclinic Gd2O3:Er3+ nanoparticles prepared by laser ablation in liquid
Authors: Deng Hua-Wei , Chen Di-Hu
Published: February 2022

Multifunctional luminescent materials are attracting attention nowadays. In this work, monoclinic Gd2O3:Er3+ nanoparticles, which possess up-conversion luminescence and down-conversion luminescence properties, were successfully synthesized by laser ablation in liquid (LAL) technique. Up-conversion luminescence and down-conversion luminescence of monoclinic Gd2O3:Er3+ nanoparticles were got under the excitation of 980 nm and 379 nm, respectively. In addition, tunable luminescence was got. Furthermore, the cytotoxicity of the nanoparticles is low and the fluorescence of the nanoparticles in cell is also strong enough. The results indicate that the Gd2O3:Er3+ nanoparticles synthesized by LAL technique are promising candidates for bio-imaging or other fields that require controllable fluorescence.
Onion-structured transition metal dichalcogenide nanoparticles by laser fabrication in liquids and atmospheres
Authors: Zhou Le , Zhang Hongwen , Zhao Qian , Cai Weiping
Published: February 2022

Since the discovery of transition metal dichalcogenide (TMDC) nanoparticles (NPs) with the onion-like structure, many efforts have been made to develop their fabrication methods. Laser fabrication (LF) is one of the most promising methods to prepare onion-structured TMDC (or OS-TMDC) NPs due to its green, flexible, and scalable syntheses. In this mini-review article, we systematically introduce various laser-induced OS-TMDC (especially the OS-MoS2) NPs, their formation mechanism, properties, and applications. The preparation routes mainly include laser ablation in liquids and atmospheres, and laser irradiation in liquids. The various formation mechanisms are then introduced based on the different preparation routes, to describe the formations of the corresponding OS-NPs. Finally, some interesting properties and novel applications of these NPs are briefly demonstrated, and a short outlook is also given. This review could help to understand the progress of the laser-induced OS-TMDC NPs and their applications.
Collider search of light dark matter model with dark sector decay *
Authors: Cheng Yu , Liao Wei , Yan Qi-Shu
Published: February 2022

We explore the possibility that the dark matter relic density is not produced by a thermal mechanism directly, but by the decay of other heavier dark-sector particles which themselves can be produced by the thermal freeze-out mechanism. Using a concrete model with light dark matter from dark sector decay, we study the collider signature of the dark sector particles associated with Higgs production processes. We find that future lepton colliders could be a better place to probe the signature of this kind of light dark matter model than hadron colliders such as LHC. Also, we find that a Higgs factory with center-of-mass energy 250 GeV has a better potential to resolve the signature of this kind of light dark matter model than a Higgs factory with center-of-mass energy 350 GeV.
Scalar Pre-potentials for Spinor and Tensor Fields on Spacetime
Authors: Tucker R. W. , Walton T. J.
Published: February 2022

We review a technique for solving a class of classical linear partial diferential systems of relevance to physics in Minkowski spacetime. All the equations are amenable to analysis in terms of complex solutions in the kernel of the scalar Laplacian and a complexifed Hertz potential. The complexifcation prescription ensures the existence of regular physical solutions with chirality and propagating, non-singular, pulse-like characteristics that are bounded in all three spatial dimensions. The technique is applied to the source-free Maxwell, Bopp-Landé-Podolsky and linearised Einstein feld systems, and particular solutions are used for constructing classical models describing single-cycle laser pulses and a mechanism is discussed for initiating astrophysical jets. Our article concludes with a brief introduction to spacetime Cliford algebra ideals that we use to represent spinor felds. We employ these to demonstrate how the same technique used for tensor felds enables one to construct new propagating, chiral, non-singular, pulse-like spinor solutions to the massless Dirac equation in Minkowski spacetime.
Host oligodendrogliopathy and α-synuclein strains dictate disease severity in multiple system atrophy
Authors: Torre-Muruzabal Teresa , Van der Perren Anke , Coens Audrey , Gelders Géraldine , Janer Anna Barber , Camacho-Garcia Sara , Klingstedt Therése , Nilsson Peter , Stefanova Nadia , Melki Ronald , Baekelandt Veerle , Peelaerts Wouter
Published: February 2022

Multiple system atrophy is a progressive neurodegenerative disease with prominent autonomic and motor features. During early stages, different subtypes of the disease are distinguished by their predominant parkinsonian or cerebellar symptoms, reflecting its heterogeneous nature. The pathognomonic feature of multiple system atrophy is the presence of α-synuclein (αSyn) protein deposits in oligodendroglial cells. αSyn can assemble in specific cellular or disease environments and form αSyn strains with unique structural features, but the ability of αSyn strains to propagate in oligodendrocytes remains elusive.

Recently, it was shown that αSyn strains with related conformations exist in the brains of patients. Here, we investigated whether different αSyn strains can influence multiple system atrophy progression in a strain-dependent manner. To this aim, we injected two recombinant αSyn strains (fibrils and ribbons) in multiple system atrophy transgenic mice and found that they determined disease severity in multiple system atrophy via host-restricted and cell-specific pathology in vivo.

αSyn strains significantly impact disease progression in a strain-dependent way via oligodendroglial, neurotoxic and immune-related mechanisms. Neurodegeneration and brain atrophy were accompanied by unique microglial and astroglial responses and the recruitment of central and peripheral immune cells. The differential activation of microglial cells correlated with the structural features of αSyn strains both in vitro and in vivo. Spectral analysis showed that ribbons propagated oligodendroglial inclusions that were structurally distinct from those of fibrils, with resemblance to oligodendroglial inclusions, in the brains of patients with multiple system atrophy.

This study, therefore, shows that the multiple system atrophy phenotype is governed by both the nature of the αSyn strain and the host environment and that by injecting αSyn strains into an animal model of the disease, a more comprehensive phenotype can be established.
p70S6 kinase regulates oligodendrocyte differentiation and is active in remyelinating lesions
Authors: Benardais Karelle , Ornelas Isis M. , Fauveau Melissa , Brown Tanya L. , Finseth Lisbet T. , Panic Radmila , Deboux Cyrille , Macklin Wendy B. , Wood Teresa L. , Nait-Oumesmar Brahim
Published: February 2022

The p70 ribosomal S6 kinases (p70 ribosomal S6 kinase 1 and p70 ribosomal S6 kinase 2) are downstream targets of the mechanistic target of rapamycin signalling pathway. p70 ribosomal S6 kinase 1 specifically has demonstrated functions in regulating cell size in Drosophila and in insulin-sensitive cell populations in mammals. Prior studies demonstrated that the mechanistic target of the rapamycin pathway promotes oligodendrocyte differentiation and developmental myelination; however, how the immediate downstream targets of mechanistic target of rapamycin regulate these processes has not been elucidated. Here, we tested the hypothesis that p70 ribosomal S6 kinase 1 regulates oligodendrocyte differentiation during developmental myelination and remyelination processes in the CNS. We demonstrate that p70 ribosomal S6 kinase activity peaks in oligodendrocyte lineage cells at the time when they transition to myelinating oligodendrocytes during developmental myelination in the mouse spinal cord. We further show p70 ribosomal S6 kinase activity in differentiating oligodendrocytes in acute demyelinating lesions induced by lysophosphatidylcholine injection or by experimental autoimmune encephalomyelitis in mice. In demyelinated lesions, the expression of the p70 ribosomal S6 kinase target, phosphorylated S6 ribosomal protein, was transient and highest in maturing oligodendrocytes. Interestingly, we also identified p70 ribosomal S6 kinase activity in oligodendrocyte lineage cells in active multiple sclerosis lesions. Consistent with its predicted function in promoting oligodendrocyte differentiation, we demonstrate that specifically inhibiting p70 ribosomal S6 kinase 1 in cultured oligodendrocyte precursor cells significantly impairs cell lineage progression and expression of myelin basic protein. Finally, we used zebrafish to show in vivo that inhibiting p70 ribosomal S6 kinase 1 function in oligodendroglial cells reduces their differentiation and the number of myelin internodes produced. These data reveal an essential function of p70 ribosomal S6 kinase 1 in promoting oligodendrocyte differentiation during development and remyelination across multiple species.
CircRNA_Maml2 promotes the proliferation and migration of intestinal epithelial cells after severe burns by regulating the miR-93-3p/FZD7/Wnt/β-catenin pathway
Authors: Zhang Wenwen , Liao Yu , Lou Jiaqi , Zhuang Mengmeng , Yan Hao , Li Qi , Deng Yuequ , Xu Xiaohu , Wen Dandan , Sun Yong
Published: February 2022

Background

Circular RNA (circRNA) plays key regulatory roles in the development of many diseases. However the biological functions and potential molecular mechanisms of circRNA in the injury and repair of intestinal mucosa in mice after severe burns are yet to be elucidated.

Methods

Cell counting kit-8 (CCK-8), 5-ethynyl-2′-deoxyuridine (EdU), wound healing and transwell assays were used to detect cell proliferation and migration ability. Real-time quantitative PCR was used to identify the expression of circRNA, microRNA and messenger RNA. Nuclear and cytoplasmic separation experiments were employed to perceive the location of circRNA_Maml2. Finally, in vitro and in vivo experiments were conducted to study the repairing effect of circRNA_Maml2 on the intestinal mucosa of mice after severe burns.

Results

When compared with the control group, the expression of circRNA_Maml2 was significantly reduced in the severe burn group. Furthermore, overexpression of circRNA_Maml2 promoted the proliferation and migration of CT26.wt cells in vivo and the repair of damaged intestinal mucosa in vitro. CircRNA_Maml2 acted as a sponge adsorption molecule for miR-93-3p to enhance the expression of frizzled class receptor 7 and activate the downstream Wnt/β-catenin pathway, thereby promoting the repair of the intestinal mucosa.

Conclusions

Our findings demonstrate that circRNA_Maml2 regulates the miR-93-3p/FZD7/Wnt/β-catenin pathway and promotes the repair of damaged intestinal mucosa. Hence, circRNA_Maml2 is a potential therapeutic target to promote intestinal mucosal repair.
Sex-dependent multimodal response profiles to psychosocial stress
Authors: Kuhn Leandra , Noack Hannes , Wagels Lisa , Prothmann Anna , Schulik Anna , Aydin Ece , Nieratschker Vanessa , Derntl Birgit , Habel Ute
Published: February 2022

Introduction

Sex differences in stress reactions are often reported in the literature. However, the sex-dependent interplay of different facets of stress is still not fully understood. Particularly in neuroimaging research, studies on large samples combining different indicators of stress remain scarce.

Materials and Methods

In a functional magnetic resonance imaging study, a sample of 140 healthy participants (67 females using oral contraceptives) underwent a standardized stress induction protocol, the ScanSTRESS. During the experiment, salivary cortisol and subjective ratings were obtained at multiple time points and heart rate was recorded.

Results

Sex differences emerged in different facets of the stress response:Women reacted with enhanced subjective feelings of stress and increases in heart rate, while men showed more pronounced neural activation in stress-related brain regions such as the inferior frontal gyrus and insula. Subjective feelings of stress and (para) hippocampal activity were negatively related in women,whereas a slightly positive association was observed in men.

Discussion

These results provide further insight in the sex-specific stress response patterns. Moreover, they emphasize the role of the hippocampus in the regulation of the stress response. This paves the way for the identification of sex-dependent vulnerability factors that can, in the future, be implemented in the prevention and treatment of stress-related disorders.
Go V.I.R.A.L.: Social Media Engagement Strategies in Infectious Diseases
Authors: Langford Bradley J , Laguio-Vila Maryrose , Gauthier Timothy P , Shah Aditya
Published: February 2022

Social media has emerged as a tool to facilitate communication and dissemination of information for both patients and healthcare professionals. We describe 3 social media engagement strategies used to reach a broad and diverse audience on the topics of infectious diseases and antimicrobial stewardship, including the use of memes, a clue-based knowledge assessment quiz, and a personality quiz. We describe a novel acronym “VIRAL” to guide engaging social media strategies in healthcare, including eye catching Visuals, Interactive content, showing Respect and empathy for the audience, Adapting to new technology, and making Learning fun.
Markers of Systemic Inflammation in Acute Attacks of Ulcerative Colitis: What Level of C-reactive Protein Constitutes Severe Colitis?
Authors: Croft Anthony , Lord Anton , Radford-Smith Graham
Published: February 2022

Background and Aims

The erythrocyte sedimentation rate [ESR] as a component of the Truelove and Witts Criteria [TWC] is the traditional inflammatory marker used for the assessment of ulcerative colitis [UC] activity. However, the C-reactive protein [CRP] is preferentially used in contemporary clinical practice. We aimed to determine the equivalent CRP cut-off for an ESR of  >30 mm/h in patients presenting with acute severe UC.

Methods

Clinical and pathological data were prospectively collected from 163 presentations of severe UC. A CRP cut-off corresponding to an ESR of  >30 mm/h was determined using confusion matrices. A validation cohort of 128 presentations was prospectively collected and analysed.

Results

A CRP cut-off of ≥12 mg/L generated an 85% positive predictive value [PPV] with a sensitivity of 95% and an accuracy of 82% for having a paired ESR of  >30 mm/h. There were no statistically significant differences between groups determined by the traditional ESR versus the new CRP-based criterion in the presenting faecal calprotectin, Mayo endoscopic subscore, or the rates of intravenous corticosteroid therapy failure and colectomy-by-discharge. Applying the CRP  ≥12 mg/L criterion to a validation cohort of 128 presentations generated a PPV of 83% and a sensitivity of 94%.

Conclusions

The proposed CRP  ≥12 mg/L cut-off is an inclusive, sensitive, and very practical alternative to ESR as part of the TWC for defining UC presentation severity. It demonstrated similar performance characteristics to the classical ESR criterion when used for the assessment of acute UC disease activity. These findings were confirmed in a validation cohort.
A previously undescribed pathogenic variant in FBN1 gene causing Marfan syndrome: a case report
Authors: Suliman Asem , Yan Weiang , Yamashita Michael H , Krentz Anthony D , Mhanni Aizeddin , Garber Philip J
Published: February 2022

Background

Marfan syndrome (MFS) is an autosomal dominant multisystem connective tissue disorder with increased risk of aortopathy with a high risk of subsequent life-threatening aortic dissection. Diagnosing this condition is reliant on recognizing clinical features and genetic testing for confirming diagnosis, using the revised Ghent criteria.

Case summary

We identified a 49-year-old patient who presented with dyspnoea, with Marfan syndrome (MFS) and a previously unreported variant in the fibrillin-1 gene (FBN1), designated c.7016G>C. Prior to identifying the new gene variant, this patient did not meet the revised Ghent criteria for MFS diagnosis. We present clinical and molecular evidence supporting the likely pathogenic nature of this variant, leading to earlier therapy and intervention.

Discussion

The discovery of a new pathogenic gene will expand the current aortopathy and MFS database and may lead to more informed clinical management decisions for the timing and nature of interventions.
The association between urinary sodium concentration (UNa) and outcomes of acute heart failure: a systematic review and meta-analysis
Authors: Khorramshahi Bayat Maryam , Ngo Linh , Mulligan Andrew , Chan Wandy , McKenzie Scott , Hay Karen , Ranasinghe Isuru
Published: February 2022

Aims

Urinary sodium concentration (UNa) is a simple test advocated to assess diuretics efficacy and predict outcomes in acute heart failure (AHF). We performed a systematic review and meta-analysis to examine the association of UNa with outcomes of AHF.

Methods and results

We searched Embase and Medline for eligible studies that reported the association between UNa and outcomes of urinary output, weight loss, worsening renal function, length of hospital stay, re-hospitalization, worsening heart failure, and all-cause mortality in AHF. Nineteen observational studies out of 1592 screened records were included. For meta-analyses of outcomes, we grouped patients into high vs. low UNa, with most studies defining high UNa as >48–65 mmol/L. In the high UNa group, pooled data showed a higher urinary output (mean difference 502 mL, 95% CI 323–681, P < 0.01), greater weight loss (mean difference 1.6 kg, 95% CI 0.3–2.9, P = 0.01), and a shorter length of stay (mean difference −1.4 days, 95% CI −2.8 to −0.1, P = 0.03). There was no significant difference in worsening kidney function (OR 0.54, 95% CI 0.25–1.16, P = 0.1). Due to the small number of studies, we did not report pooled estimates for re-hospitalization and worsening heart failure. High UNa was associated with lower odds of 30-day (OR 0.27; 95% CI 0.14–0.49, P < 0.01), 90-day (OR 0.39,95% CI 0.25–0.59, P < 0.01) and 12-month (OR 0.35; 95% CI 0.20–0.61, P < 0.01) mortality.

Conclusion

High UNa after diuretic administration is associated with higher urinary output, greater weight loss, shorter length of stay, and lower odds of death. UNa is a promising marker of diuretic efficacy in AHF which should be confirmed in randomized trials.
Use of extracorporeal membrane oxygenation in non-elective major thoracic surgery for infectious lung abscess
Authors: Schweigert Michael , Dubecz Attila , Giraldo Ospina Carlos F , Spieth Peter , Almeida Ana Beatriz , Richter Torsten , Witzigmann Helmut , Stein Hubert J
Published: February 2022

OBJECTIVES

Extracorporeal membrane oxygenation (ECMO) support for elective cardiothoracic surgery is well established. In contrast, there are not much data regarding the usefulness and outcome of ECMO in non-elective major lung resections for infectious lung abscess.

METHODS

All patients undergoing non-elective major lung surgery for infectious lung abscess at 5 centres in Germany, UK and Spain were enrolled in a prospective database. Malignant disorders and intrathoracic complications of other procedures were excluded.

RESULTS

There were 127 patients. The median age was 59 years (interquartile range 18.75). The mean Charlson index of comorbidity was 2.83 (standard deviation 2.57). Surgical procedures were lobectomy (89), pneumectomy (20) and segmentectomy (18). ECMO was used for 10 patients (pneumectomy 2, lobectomy 8) and several more received pre-ECMO treatment. Mortality was 17/127. Intraoperatively no ECMO-associated complications were encountered. EMCO [1/10 vs 16/117; odds ratio (OR): 0.70, 95% confidence interval (CI) 0.08–5.91, P = 0.74] and the extent of pulmonary resection were not associated with higher mortality. Preoperative sepsis (OR: 17.84, 95% CI 2.29–139.28, P < 0.01), preoperative air leak (OR: 13.12, 95% CI 4.10–42.07, P < 0.001), acute renal failure (OR: 7.00, 95% CI 2.19–22.43, P < 0.01) and Charlson index of comorbidity ≥3 (OR: 10.83, 95% CI 2.36–49.71, P < 0.01) were associated with significantly higher mortality.

CONCLUSIONS

The application of ECMO is widening the possibilities for successful surgical management of infectious, non-malignant lung abscesses. Particularly, patients with marginal functional operability benefit from the availability and readiness to use ECMO. Mortality is determined by the burden of pre-existent comorbidity, severe sepsis and septic shock.
Efficacy and safety of proton pump inhibitors versus histamine-2 receptor blockers in the cardiac surgical population: insights from the PEPTIC trial
Authors: van Diepen Sean , Coulson Tim , Wang Xiaoming , Opgenorth Dawn , Zuege Danny J , Harris Jo , Agyemang Malik , Niven Daniel J , Bellomo Rinaldo , Wright Stephen E , Young Paul J , Bagshaw Sean M ,   for the PEPTIC study investigators and the ANZICS Clinical Trials Group
Published: February 2022

OBJECTIVES

The comparative effectiveness and safety of proton pump inhibitors (PPIs) versus histamine-2 receptor blockers for stress ulcer prophylaxis in the cardiac surgical intensive care unit population is uncertain. Although the Proton Pump Inhibitors versus Histamine-2 Receptor Blockers for Ulcer Prophylaxis Therapy in the Intensive Care Unit (PEPTIC) trial reported a higher risk of mortality in the PPI arm with no difference in gastrointestinal bleeding, detailed information on surgical variables and clinically relevant surgical subgroups was not available.

METHODS

The analysis included all Canadian cardiac surgery patients enrolled in the PEPTIC trial. Data were electronically linked using unique patient identifiers to a clinical information system. Outcomes of interest included in-hospital mortality, gastrointestinal bleeding, Clostridium difficile infections, ventilator-associated conditions and length of stay.

RESULTS

We studied 823 (50.6%) randomized to PPIs and 805 (49.4%) to histamine-2-receptor blockers. In the intention-to-treat analysis, there were no differences in hospital mortality [PPI: 4.3% vs histamine-2 receptor blockers: 4.8%, adjusted odds ratio (aOR) 0.97, 95% confidence interval (CI) 0.55–1.70], gastrointestinal bleeding (3.9% vs 4.8%, aOR 1.09, 95% CI 0.66–1.81), C. difficile infections (0.9% vs 0.1%, aOR 0.18, 95% CI 0.02–1.59), ventilator-associated conditions (1.6% vs 1.7%, aOR 0.92, 95% CI 0.85–1.00) or median length of stay (9.2 vs 9.8 days, adjusted risk ratio 1.06, 85% CI 0.99–1.13). No significant treatment differences were observed among subgroups of interest or per-protocol populations.

CONCLUSIONS

In a secondary analysis of cardiac surgery patients enrolled in the PEPTIC trial in Canada, no differences in effectiveness or safety were observed between use of PPIs and histamine-2 receptor blockers for stress ulcer prophylaxis.

Clinical trial registration number

anzctr.org.au identifier: ACTRN12616000481471.
Intensity of Grandparent Caregiving, Health, and Well-Being in Cultural Context: A Systematic Review
Authors: Chan Athena C Y , Lee Sun-Kyung , Zhang Jingchen , Banegas Jasmine , Marsalis Scott , Gewirtz Abigail H
Published: February 2022

Background and Objectives

Grandparents are key resources in grandchildren care globally. However, mixed findings indicated that multiple role engagement may enhance well-being and bring demands on grandparent caregivers in different contexts. This systematic review examines the association between the intensity of grandparent caregiving and their health and well-being (i.e., physical, mental, cognitive, and life satisfaction) by continent and country/region.

Research Design and Methods

Systematic searches were conducted in 4 databases. Peer-reviewed articles with quantitative designs published between 1990 and November 2021 were identified. A rigorous selection process was followed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The studies were critically appraised, and their results were narratively synthesized.

Results

Sixty-five articles from 29 countries/regions were included. Findings suggested a concave curvilinear relationship between the intensity of grandparent caregiving and their health and well-being, with the optimal caregiving intensity varying across sociocultural contexts. In Europe, Oceania, the Middle East, and South America, providing supplementary or occasional care seems beneficial for grandparents’ health and well-being, especially supporting dual-earner families. In East Asia, economic resources appear to buffer the adverse effect of primary care on grandparents’ well-being. In the United States, findings vary across ethnicity/race.

Discussion and Implications

Collectively, the intensity of grandparent caregiving, health, and well-being is complicated by grandparents’ roles in the family and cultural differences. Acknowledging the bidirectional relationship between well-being and grandparents’ capacity for providing care, the well-being as outcome is a limitation. Despite so, this systematic review calls for culturally-tailored family programs to support grandparent caregiving.
Sexuality-based stigma and access to care: intersecting perspectives between healthcare providers and men who have sex with men in HIV care centres in Senegal
Authors: Ndione Albert Gautier , Procureur Fanny , Senne Jean-Noël , Cornaglia Francesca , Gueye Khady , Ndour Cheikh Tidiane , Lépine Aurélia
Published: February 2022

Men who have sex with men (MSM) in Senegal face a challenging socio-legal context, marked by homophobia and the illegality of homosexuality. In addition, human immunodeficiency virus (HIV) prevalence among MSM is 27.6%, 46 times greater than the one in the general population (0.5%). Nevertheless, access to healthcare by MSM may be hampered by stigmatizing attitudes from health facility staff (medical and non-medical). This article describes the health facility staff/MSM relationship and analyses its effects on access to healthcare by MSM. The data used were collected through a field survey based on observations and qualitative interviews conducted in 2019 and 2020 with 16 MSM, 1 non-governmental organization (NGO) staff and 9 healthcare providers in Dakar (the capital city) and Mbour (secondary city on the West Coast) hospitals. The data were subject to a thematic analysis assisted by the ATLAS software. The relationship between MSM and healthcare providers is ambiguous. On the one hand, healthcare providers are torn between their professional duty to treat MSM and the cost of being stigmatized by other colleagues. Therefore, they often limit their empathy with MSM within the hospital context. On the other hand, MSM, trusting in the confidentiality of healthcare providers, feel safe in the care pathway. However, we identify the following stigmatizing factors limiting access to care include (1) fear of meeting a relative, (2) difficult relationships with non-medical support staff (mainly security guards), (3) HIV status disclosure and (4) potential conflicts with other MSM. This study is unique as it includes non-medical staff in its respondents. It shows that hospitals are divided into several areas, based on the stigma perceived by MSM. It is important to map out MSM’s care trajectories and spaces and to identify all types of staff working within them, including non-medical staff, and enrol them in stigma reduction interventions.
Choroidal endothelial and macrophage gene expression in atrophic and neovascular macular degeneration
Authors: Voigt Andrew P , Mullin Nathaniel K , Mulfaul Kelly , Lozano Lola P , Wiley Luke A , Flamme-Wiese Miles J , Boese Erin A , Han Ian C , Scheetz Todd E , Stone Edwin M , Tucker Budd A , Mullins Robert F
Published: February 2022

The human choroid is a heterogeneous, highly vascular connective tissue that dysfunctions in age-related macular degeneration (AMD). In this study, we performed single-cell RNA sequencing on 21 human choroids, 11 of which were derived from donors with early atrophic or neovascular AMD. Using this large donor cohort, we identified new gene expression signatures and immunohistochemically characterized discrete populations of resident macrophages, monocytes/inflammatory macrophages and dendritic cells. These three immune populations demonstrated unique expression patterns for AMD genetic risk factors, with dendritic cells possessing the highest expression of the neovascular AMD-associated MMP9 gene. Additionally, we performed trajectory analysis to model transcriptomic changes across the choroidal vasculature, and we identified expression signatures for endothelial cells from choroidal arterioles and venules. Finally, we performed differential expression analysis between control, early atrophic AMD, and neovascular AMD samples, and we observed that early atrophic AMD samples had high expression of SPARCL1, a gene that has been shown to increase in response to endothelial damage. Likewise, neovascular endothelial cells harbored gene expression changes consistent with endothelial cell damage and demonstrated increased expression of the sialomucins CD34 and ENCM, which were also observed at the protein level within neovascular membranes. Overall, this study characterizes the molecular features of new populations of choroidal endothelial cells and mononuclear phagocytes in a large cohort of AMD and control human donors.