Ionic Conductivity of a Lithium-Doped Deep Eutectic Solvent: Glass Formation and Rotation-Translation Coupling

Deep eutectic solvents with admixed lithium salts are considered as electrolytes in electrochemical devices, such as batteries or supercapacitors. Compared to eutectic mixtures of hydrogen-bond donors and lithium salts, their raw-material costs are significantly lower. Not much is known about glassy freezing and rotational-translation coupling of such systems. Here, we investigate these phenomena by applying dielectric spectroscopy to the widely studied deep eutectic solvent glyceline, to which 1 and 5 mol % LiCl were added. Our study covers a wide temperature range, including a deeply supercooled state. The temperature dependences of the detected dipolar reorientation dynamics and ionic direct current (dc) conductivity reveal the signatures of glassy freezing. In comparison to pure glyceline, the lithium admixture leads to a reduction of ionic conductivity, which is accompanied by a reduction of the rotational dipolar mobility. However, this reduction is much smaller than that for deep eutectic solvents (DESs), where one main component is lithium salt, which we trace back to the lower glass-transition temperatures of lithium-doped DESs. In contrast to pure glyceline, the ionic and dipolar dynamics become increasingly decoupled at low temperatures and obey a fractional Debye-Stokes-Einstein relation, as previously found in other glass-forming liquids. The obtained results demonstrate the relevance of decoupling effects and glass transition to the enhancement of the technically relevant ionic conductivity in such lithium-doped DESs.

Frontal alpha asymmetry is associated with chronic stress and depression, but not with somatoform disorders

Cardinal characteristics of somatoform disorders (SFDs) are worry of illness, and impaired affective processing. We used relative frontal alpha asymmetry (FAA), a method to measure functional lateralization of affective processing, to investigate psychobiological correlates of SFDs. With alpha activity being inversely related to cortical network activity, relative FAA refers to alpha activity on the right frontal lobe minus alpha activity on the left frontal lobe. Less relative left frontal activity, reflected by negative FAA scores, is associated with lower positive and greater negative affectivity, such as observed in depression. Due to its negative affective component (illness anxiety), we expected to find less relative left frontal activity pattern in SFDs, and positive associations with self-reported chronic stress and depression symptoms. We recorded resting-state EEG activity with 64 electrodes, placed in a 10-10 system in 26 patients with a primary SFD, 23 patients with a major depressive disorder and 25 healthy control participants. The groups did not differ in FAA. Nevertheless, across all participants, less relative left frontal activity was associated with chronic stress and depression symptoms. We concluded that FAA may not serve as an indicator of SFDs. As the relationship of FAA and depressive symptoms was fully mediated by chronic stress, future studies have to clarify whether the association between FAA and chronic stress may represent a shared underlying factor for the manifestation of mental health complaints, such as depression.

Translational and reorientational dynamics in carboxylic acid-based deep eutectic solvents

The glass formation and the dipolar reorientational motions in deep eutectic solvents (DESs) are frequently overlooked, despite their crucial role in defining the room-temperature physiochemical properties. To understand the effects of these dynamics on the ionic conductivity and their relation to the mechanical properties of the DES, we conducted broadband dielectric and rheological spectroscopy over a wide temperature range on three well-established carboxylic acid-based natural DESs. These are the eutectic mixtures of choline chloride with oxalic acid (oxaline), malonic acid (maline), and phenylacetic acid (phenylaceline). In all three DESs, we observe signs of a glass transition in the temperature dependence of their dipolar reorientational and structural dynamics, as well as varying degrees of motional decoupling between the different observed dynamics. Maline and oxaline display a breaking of the Walden rule near the glass-transition temperature, while the relation between the dc conductivity and dipolar relaxation time in both maline and phenylaceline is best described by a power law. The glass-forming properties of the investigated systems not only govern the orientational dipolar motions and rheological properties, which are of interest from a fundamental point of view, but they also affect the dc conductivity, even at room temperature, which is of high technical relevance.

Rotational dynamics, ionic conductivity, and glass formation in a ZnCl2-based deep eutectic solvent

Glass formation and reorientational motions are widespread but often-neglected features of deep eutectic solvents although both can be relevant for the technically important ionic conductivity at room temperature. Here, we investigate these properties for two mixtures of ethylene glycol and ZnCl2, which were recently considered superior electrolyte materials for application in zinc-ion batteries. For this purpose, we employed dielectric spectroscopy performed in a broad temperature range, extending from the supercooled state at low temperatures up to the liquid phase around room temperature and beyond. We find evidence for a relaxation process arising from dipolar reorientation dynamics, which reveals the clear signatures of glassy freezing. This freezing also governs the temperature dependence of the ionic dc conductivity. We compare the obtained results with those for deep eutectic solvents that are formed by the same hydrogen-bond donor, ethylene glycol, but by two different salts, choline chloride and lithium triflate. The four materials reveal significantly different ionic and reorientational dynamics. Moreover, we find varying degrees of decoupling of rotational dipolar and translational ionic motions, which can partly be described by a fractional Debye-Stokes-Einstein relation. The typical glass-forming properties of these solvents strongly affect their room-temperature conductivity.

Games, hormones, and "dark" personalities: Dark tetrad and the effects of violent gaming on aggression, cortisol, and testosterone

We investigated how playing a violent versus non-violent video game affects cortisol and testosterone levels, whether these hormonal changes increase implicit aggressive cognition, and whether so-called Dark Tetrad personality traits (i.e., Machiavellianism, psychopathy, narcissism, everyday sadism) moderate these effects. Fifty-four men played either a violent or a non-violent video game for 25 min. Participants provided salivary samples at the beginning of the experiment (T1), after 25 min of gameplay (T2), and 20 min after gameplay ended (T3). In the violent condition, participants showed a significant decrease in cortisol levels (T1 to T2) and a significant negative trend in cortisol levels from T1 to T3. Moreover, higher Machiavellianism scores were related to a significantly stronger decrease in cortisol (T1 to T2) in this condition. In the non-violent condition, however, participants with higher scores in Machiavellianism had a higher increase in cortisol (T1 to T2). In contrast to changes in hormonal levels, there were no significant effects on implicit aggressive cognition. The present findings illustrate the complex interplay between personality, hormones, and game content, thus further specifying current notions on the effects of violent video games. Playing a violent video game can have a stress-reducing calming effect depending on personality traits such as Machiavellianism and the psychological need satisfaction associated with it. Also, the fact that VVG exposure was not automatically accompanied by an aggression-increasing effect proves that simple cause-effect models are not sufficiently specified without taking the underlying mechanisms into account.

Development and initial validation of a self-report measure to assess eating disorder-specific interoceptive perception

Interoceptive deficits-particularly with respect to the perception of emotions, hunger, and satiety-constitute important targets for intervention in eating disorders (EDs). Suitable self-report measures to identify these deficits, however, are lacking. We, therefore, developed and validated a multidimensional questionnaire to assess eating disorder-specific interoceptive perception (EDIP) in terms of the ability to perceive and discriminate between emotions, hunger, and satiety. In two independent samples with a total of 2058 individuals (22.74% with self-reported EDs), exploratory and confirmatory factor analyses revealed a four-factor solution of the EDIP Questionnaire (EDIP-Q) with the subscales Emotions, Hunger, Satiety, and Discrimination. The EDIP-Q has sound psychometric properties and was related to convergent questionnaires but unrelated to divergent self-report measures, supporting its construct validity. Participants with self-reported EDs had significantly lower EDIP-Q scores compared to participants without self-reported ED diagnosis. While individuals with self-reported anorexia nervosa (AN), bulimia nervosa (BN), and binge-eating disorder (BED) report similar difficulties in perceiving emotions, participants with BN and BED report greater difficulties in perceiving satiety and differentiating between hunger and emotional states compared to participants with AN. In contrast, individuals with AN report higher sensibility to satiety but lower sensibility to hunger compared to individuals with BN and BED. The EDIP-Q is a valuable clinical tool to establish profiles of deficits in EDIP that provide the basis for developing more targeted treatment approaches for EDs. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Lower gastric sensitivity in quiescent inflammatory bowel disease than in irritable bowel syndrome

OBJECTIVE

Visceral hypersensitivity is considered a key symptom in inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS), both of which seriously affect health-related quality of life (HrQoL). Previous findings are mostly based on invasive procedures that may interfere with the assessment of visceral perception. The current study, therefore, investigates whether IBD and IBS are characterized by altered perception of 'natural' gastric distensions ('interoception').

METHODS

Twenty IBD patients in remission (13 Crohn's disease, 7 ulcerative colitis), 12 IBS patients, and 20/12 matched healthy control (HC) individuals, respectively, underwent the water load test, in which they could drink ad libitum until the subjective thresholds of satiation (stage 1) and fullness (stage 2) were reached. Gastric motility was assessed using electrogastrography.

RESULTS

IBD patients drank significantly more water until satiation than IBS patients, whereas no differences between patients and HC groups were observed. Electrogastrographic patterns were comparable between groups, suggesting no pathologies in gastric motility in IBD or IBS. The amount of water consumed until satiation negatively correlated with HrQoL related to bowel symptoms in IBD patients, but was positively associated with emotional well-being in IBS patients.

CONCLUSION

Our findings implicate relative gastric hypersensitivity in IBS, and relative hyposensitivity in IBD patients, which are both related to specific HrQoL aspects.

A highly versatile biopolymer-based platform for the maturation of human pluripotent stem cell-derived cardiomyocytes enables functional analysis in vitro and 3D printing of heart patches

Human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) represent a valuable tool for in vitro modeling of the cardiac niche and possess great potential in tissue engineering applications. However, conventional polystyrene-based cell culture substrates have adverse effects on cardiomyocytes in vitro due to the stress applied by a stiff substrate on contractile cells. Ultra-high viscosity alginates offer a unique versatility as tunable substrates for cardiac cell cultures due to their biocompatibility, flexible biofunctionalization, and stability. In this work, we analyzed the effect of alginate substrates on hPSC-CM maturity and functionality. Alginate substrates in high-throughput compatible culture formats fostered a more mature gene expression and enabled the simultaneous assessment of chronotropic and inotropic effects upon beta-adrenergic stimulation. Furthermore, we produced 3D-printed alginate scaffolds with differing mechanical properties and plated hPSC-CMs on the surface of these to create Heart Patches for tissue engineering applications. These exhibited synchronous macro-contractions in concert with more mature gene expression patterns and extensive intracellular alignment of sarcomeric structures. In conclusion, the combination of biofunctionalized alginates and human cardiomyocytes represents a valuable tool for both in vitro modeling and regenerative medicine, due to its beneficial effects on cardiomyocyte physiology, the possibility to analyze cardiac contractility, and its applicability as Heart Patches.

The relationship between self-reported chronic stress, physiological stress axis dysregulation and medically-unexplained symptoms

The positive feedback model of medically-unexplained symptoms posits that chronic stress affects the activity of the physiological stress axes, which in turn generates medically-unexplained symptoms. As a first step to empirically test its model assumptions, we investigated potential associations between chronic stress, physiological stress axis activity and medically-unexplained in a cross-sectional study. One hundred-ninety-nine healthy individuals provided self-reports on chronic stress and medically-unexplained symptoms, resting heart rate/variability (HR/HRV; e.g., root mean square of successive differences/RMSSD, low frequency/LF power), cortisol awakening response (CAR) and diurnal cortisol. Significant positive contributors to medically-unexplained symptoms were the chronic stress scales 'lack of social appreciation' and 'chronic worries', as well as CAR and LF HRV; diurnal cortisol was a negative contributor. Mediation analyses showed that the impact of neural indicators associated with physiological stress axis activity (HR/HRV) related to medically-unexplained symptoms, which was mediated by chronic stress, whereas the mediation effect as suggested by the positive feedback model was not significant. These cross-sectional findings do not support the positive feedback model. Longitudinal studies are required to conclude about potential mechanistic and causal relationships in the model. Nevertheless, our mediation analyses give first indication that the constitution of physiological stress axes may play a major role in how stressors are perceived and which kind of health-consequences (e.g., medically-unexplained symptoms) this may have.

Reduced concentration performance and heartbeat-evoked potential in individuals with a history of a SARS-CoV-2 infection

The goal of characterizing long-term psychological and neural consequences of a SARS-CoV-2 infection has recently gained importance. Here, we examined the effect of a prior SARS-CoV-2 infection on neural markers of exteroceptive (P300) and interoceptive (heartbeat-evoked potential; HEP) signal processing, as well as on neuropsychological tests of attention, inhibition and episodic memory, in 23 adults with a self-reported history of SARS-CoV-2 infection versus 23 healthy controls. We found that the group with a prior infection showed decreased HEP (but not P300) amplitudes, as well as reduced attention/concentration performance. These results suggest that SARS-CoV-2 may damage neural structures of cardiac interoception, thereby potentially contributing to cognitive and psychological long-term deficits. Modulations of interoceptive processing after a SARS-CoV-2 infection are thus a promising target for future research.

A rabbit model for outer retinal atrophy caused by surgical RPE removal

PURPOSE

We aimed to establish a rabbit model with retinal atrophy induced by an iatrogenic retinal pigment epithelium (RPE) removal, for future testing of the efficacy and safety of cell therapy strategies.

METHODS

A localized detachment of the retina from the RPE/choroid layer was created in 18 pigmented rabbits. The RPE was removed by scraping with a custom-made extendable loop instrument. The resulting RPE wound was observed over a time course of 12 weeks with optical coherence tomography and angiography. After 4 days (group 1) and 12 weeks (group 2), histology was done and staining with hematoxylin and eosin, as well as immunofluorescence performed to further investigate the effects of debridement on the RPE and the overlying retina.

RESULTS

Already after 4 days, we observed a closure of the RPE wound by proliferating RPE and microglia/macrophage cells forming a multilayered clump. This pattern continued over the observation time course of 12 weeks, whereby the inner and outer nuclear layer of the retina became atrophic. No neovascularization was observed in the angiograms or histology. The observed changes were limited to the site of the former RPE wound.

CONCLUSIONS

Localized surgical RPE removal induced an adjacent progressive retinal atrophy. Altering the natural course of this model may serve as a basis to test RPE cell therapeutics.

Safety and performance assessment of hyaluronic acid-based vitreous substitutes in patients with phthisis bulbi

PURPOSE

To assess the safety and performance of hyaluronic acid-based vitreous substitutes in phthitic eyes.

METHODS

In this retrospective interventional study a total of 21 eyes from 21 patients with phthisis bulbi were treated at the Eye Clinic Sulzbach between August 2011 and June 2021. Patients who underwent a 23G pars plana vitrectomy received a vitreous substitute composed of (I) a non-crosslinked hyaluronic acid (Healon GV), (II) a crosslinked hyaluronic acid-based hydrogel (UVHA), or (III) silicone oil (SO-5000). Main outcome measures were the intraocular pressure (IOP), the visual acuity and the structural integrity of the retina and choroid assessed by optical coherence tomography.

RESULTS

An increase in IOP ≥ 5 mmHg was achieved with SO-5000 in 5/8 eyes (6/10 interventions, 60.0%) for 36.4 ± 39.5 days, with Healon GV in 4/8 eyes (7/11 interventions, 63.6%) for 82.6 ± 92.5 days and with UVHA in 4/5 eyes (5/6 interventions, 83.3%) for 93.6 ± 92.5 days. Visual acuity increased in 5/21 eyes (23.8%), remained constant in 12/21 eyes (57.1%) and decreased in 4/21 eyes (19.0%). No enucleations were required during the mean follow-up time of 192 ± 182 days. The OCT images indicated the preservation of retinal structures, while choroidal folds were only diminished in UVHA eyes.

CONCLUSIONS

Hyaluronic acid-based hydrogels are biocompatible vitreous substitutes in humans and can increase and stabilize IOP in patients with phthisis bulbi for about 3 months.

Hypomorphic RAG deficiency: impact of disease burden on survival and thymic recovery argues for early diagnosis and HSCT

Patients with hypomorphic mutations in the RAG1 or RAG2 gene present with either Omenn syndrome or atypical combined immunodeficiency with a wide phenotypic range. Hematopoietic stem cell transplantation (HSCT) is potentially curative, but data are scarce. We report on a worldwide cohort of 60 patients with hypomorphic RAG variants who underwent HSCT, 78% of whom experienced infections (29% active at HSCT), 72% had autoimmunity, and 18% had granulomas pretransplant. These complications are frequently associated with organ damage. Eight individuals (13%) were diagnosed by newborn screening or family history. HSCT was performed at a median of 3.4 years (range 0.3-42.9 years) from matched unrelated donors, matched sibling or matched family donors, or mismatched donors in 48%, 22%, and 30% of the patients, respectively. Grafts were T-cell depleted in 15 cases (25%). Overall survival at 1 and 4 years was 77.5% and 67.5% (median follow-up of 39 months). Infection was the main cause of death. In univariable analysis, active infection, organ damage pre-HSCT, T-cell depletion of the graft, and transplant from a mismatched family donor were predictive of worse outcome, whereas organ damage and T-cell depletion remained significant in multivariable analysis (hazard ratio [HR] = 6.01, HR = 8.46, respectively). All patients diagnosed by newborn screening or family history survived. Cumulative incidences of acute and chronic graft-versus-host disease were 35% and 22%, respectively. Cumulative incidences of new-onset autoimmunity was 15%. Immune reconstitution, particularly recovery of naïve CD4+ T cells, was faster and more robust in patients transplanted before 3.5 years of age, and without organ damage. These findings support the indication for early transplantation.

The impact of traumatic childhood experiences on interoception: disregarding one's own body

BACKGROUND

Deficient interoception, the processing and perception of internal bodily signals, has been discussed as a mechanism underlying various mental disorders. First results indicate a mediating role of interoception in the interplay of traumatic childhood experiences and adult mental disorders. Traumatic childhood experiences may hinder the adequate processing, integration, and trust in bodily signals that are important in order to understand and regulate own needs and emotions, thereby increasing the vulnerability for mental disorders. However, an overarching study investigating alterations in different interoceptive measures and trauma-related disorders as well as their mediating role between early trauma and emotion dysregulation is still missing.

METHODS

One hundred thirty-six individuals with varying levels of traumatic childhood experiences who either had a current diagnosis of major depression, posttraumatic stress disorder, or somatic symptom disorder, or no mental disorder, took part in a multidimensional assessment of interoceptive processes, including interoceptive accuracy, sensibility, and awareness. Kruskal-Wallis tests were used to compare groups regarding interoceptive processes and associations with traumatic childhood experiences and emotion dysregulation were analyzed with Spearman correlations. Furthermore, mediation analyses were computed to examine and compare interoceptive processes as potential mediators between traumatic childhood experiences and emotion dysregulation.

RESULTS

Only body dissociation, a measure for interoceptive sensibility, was significantly reduced in individuals with a current mental disorder. Body dissociation was also the only interoceptive measure significantly associated with traumatic childhood experiences and emotion dysregulation and the only significant mediator in the relationship between traumatic childhood experiences and emotion dysregulation across groups.

CONCLUSION

Results suggest body dissociation, but not other interoceptive measures, as an important feature linking traumatic childhood experiences to current emotion dysregulation, an important transdiagnostic feature. As body dissociation refers to a habitual non-attendance or disregard of interoceptive signals, integrative therapeutic interventions could help affected individuals to overcome difficulties in emotion perception and regulation.

TRIAL REGISTRATION

The general study design was preregistered; see the German Clinical Trials Register (DRKS-ID: DRKS00015182). This study's analysis plan was not preregistered.

The BUrn Mortality Prediction (BUMP) Score - An improved mortality prediction score based on data of the German burn registry

BACKGROUND

Burn injuries constitute the fourth most common injuries globally. Patient outcomes must be currently assessed to provide appropriate patient care with high quality standards. However, existing mortality prediction scoring methods have been shown to lack accuracy in current burn patient populations. Therefore, this study aimed to validate existing scores using current patient data and assess whether new prediction parameters can provide better accuracy.

METHODS

A retrospective analysis of the patient data from the German Burn Registry between 2016 and 2019 was performed to evaluate all Abbreviated Burn Severity Index (ABSI) score parameters. All patients over 16 years of age who received intensive care were included. Descriptive statistics and logistic regression analysis were used to identify novel prediction parameters based on the parameters documented at admission and establish a new prediction score, the BUrn Mortality Prediction (BUMP) score. The quality of the new score was subsequently compared to that of the original ABSI, modified ABSI, Galeiras, Revised Baux score and TIMM. The new prediction score was then validated using patient data collected in the German Burn Registry in 2020.

RESULTS

In total, 7276 patients were included. Age; the presence of at least two comorbidities; burn injuries caused by work-related accidents, traffic accidents and suicide attempts; total burn surface area; inhalation trauma and full-thickness burns were identified as independent significant predictors of mortality (p < 0.001). Additionally, we evaluated new age groups to improve prediction accuracy. The number of comorbidities (p < 0.001) and the aetiology (burns occurring at work [p = 0.028], burns caused by traffic accidents [p < 0.001] or burns due to attempted suicide [p < 0.001]) had a significant influence on mortality. The BUMP score, which was developed based on these parameters, showed the best fitness and showed more accurate mortality prediction than all the above-mentioned scores (area under the receiver operating characteristic curve: 0.947 [0.939-0.954] compared to 0.926 [0.915-0.936], 0.928 [0.918-0.939], 0.937 [0.928-0.947], 0.939 [0.930-0.948], 0.940 [0.932-0.949] respectively).

CONCLUSIONS

A novel score (BUMP score) was developed for the purpose of external quality assessment of burn centres participating in the German burn registry, where observed and expected outcomes are compared on a hospital level, and for scientifically applications. The clinical impact of this score and its generalisability to other patient populations needs to be evaluated.

Aircraft noise exposure induces pro-inflammatory vascular conditioning and amplifies vascular dysfunction and impairment of cardiac function after myocardial infarction

AIMS

Traffic noise may play an important role in the development and deterioration of ischemic heart disease. Thus, we sought to determine the mechanisms of cardiovascular dysfunction and inflammation induced by aircraft noise in a mouse model of myocardial infarction (MI) and in humans with incident MI.

METHODS AND RESULTS

C57BL/6J mice were exposed to noise alone (average sound pressure level 72 dB; peak level 85 dB) up to 4d, resulting in pro-inflammatory aortic gene expression in the myeloid cell adhesion/diapedesis pathways. Noise alone promoted adhesion and infiltration of inflammatory myeloid cells in vascular/cardiac tissue, paralleled by an increased percentage of leukocytes with a pro-inflammatory, reactive oxygen species (ROS)-producing phenotype and augmented expression of Nox-2/phospho-NFκB in peripheral blood. Ligation of the LAD resulted in worsening of cardiac function, pronounced cardiac infiltration of CD11b+ myeloid cells and Ly6Chigh monocytes and induction of interleukin (IL) 6, IL-1β, CCL-2 and Nox-2, being aggravated by noise exposure prior to MI. MI induced stronger endothelial dysfunction and more pronounced increases in vascular ROS in animals preconditioned with noise. Participants of the population-based Gutenberg Health Cohort Study (median follow-up:11.4y) with incident MI revealed elevated CRP at baseline and worse LVEF after MI in case of a history of noise exposure and subsequent annoyance development.

CONCLUSION

Aircraft noise exposure before MI substantially amplifies subsequent cardiovascular inflammation and aggravates ischemic heart failure, facilitated by a pro-inflammatory vascular conditioning. Our translational results suggest, that measures to reduce environmental noise exposure will be helpful in improving clinical outcome of subjects with MI.

Translation of hyaluronic acid–based vitreous substitutes towards current regulations for medical devices

PURPOSE

Hydrogel-based vitreous substitutes have the potential to overcome the limitations of current clinically used endotamponades. With the goal of entering clinical trials, the present study aimed to (I) transfer the material synthesis of hyaluronic acid-based hydrogels into a routine, pharmaceutical-appropriate production and (II) evaluate the properties of the vitreous substitutes in terms of the current regulations for medical devices (MDR/ISO standards).

METHODS

The multistep manufacturing process of the vitreous substitutes, including the modification of hyaluronic acid with glycidyl methacrylate, photocopolymerization with N-vinylpyrrolidone, and successive hydrogel purification, was developed under laboratory conditions, characterized using ¹ H-NMR, FT-IR and UV/Vis spectroscopies and HPLC, and transferred towards a pharmaceutical production environment considering GMP standards. The optical and viscoelastic characteristics of the hyaluronic acid-based hydrogels were compared with those of extracted human vitreous and silicone oil. The effect of the hydrogels on the metabolic activity, proliferation and apoptosis of fibroblast (MRC-5, BJ, L929), retinal pigment epithelial (ARPE-19, hiPSC-derived RPE) and photoreceptor cells (661W) was studied as well as their mucosal tolerance via a HET-CAM assay.

RESULTS

Hyaluronic acid-based hydrogels having a suitable purity, sterility, high transparency (>90%), appropriate refractive index (1.3365) and viscoelasticity (G' > G″) were prepared in a standardized manner under controlled process conditions. The metabolic activity, proliferation and apoptosis of various cell types as well as egg choroid were unaffected by the hyaluronic acid-based vitreous substitutes, demonstrating their biocompatibility.

CONCLUSIONS

The present study demonstrates the successful transferability of the crucial synthesis steps of hyaluronic acid-based hydrogels into a routine, GMP-compliant production process while achieving the optical and viscoelastic properties, biocompatibility and purity required for their clinical use as vitreous substitutes.

Unmasking systolic impairment in HFpEF by cardiovascular magnetic resonance derived hemodynamic force assessment: insights from the HFpEF stress trial

Background

The diagnosis of heart failure with preserved ejection fraction (HFpEF) remains challenging. Exercise-stress testing is recommended in case of uncertainty; however, this approach is time-consuming and costly. Since preserved EF does not represent normal systolic function, we evaluated cardiovascular magnetic resonance (CMR) comprehensive cardiac hemodynamic forces (HDF) analyses for an in-depth characterisation of cardiac function at rest.

Methods

The HFpEF Stress Trial (DZHK-17) prospectively recruited 75 patients with exertional dyspnea, preserved EF (≥50%) and signs of diastolic dysfunction (E/e' ≥8) on echocardiography. Patients underwent right heart catheterisation, echocardiography and CMR. 68 patients entered the final study cohort (HFpEF n=34 and non-cardiac dyspnea n=34 according to pulmonary capillary wedge pressure (PCWP)). HDF assessment included left ventricular (LV) longitudinal, systolic peak and impulse, systolic/diastolic transition, E-wave deceleration as well as A-wave acceleration forces. Two patients were lost to 24 months follow-up evaluating cardiovascular mortality and hospitalisation (CVH).

Results

HDF assessment revealed impairment of LV longitudinal force in HFpEF (15.8 vs. 18.3, p=0.035) attributable to impairment of systolic peak (38.6 vs 51.6, p=0.003) and impulse (20.8 vs. 24.5, p=0.009) forces as well as late diastolic filling (−3.8 vs −5.4, p=0.029). Impairment of early diastolic filling could be observed in HFpEF patients identified at rest only but not stress (7.7 vs. 9.9, p=0.004). Impaired systolic peak was associated to CVH (HR 0.95, p=0.016) and superior for CVH prediction compared to LV global longitudinal strain (AUC 0.76 vs. 0.61, p=0.048).

Conclusions

Assessment of HDF reveals impairment of LV systolic and diastolic function in HFpEF. The value of systolic HDF assessment exceeded that of conventional deformation imaging for CVH prediction.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): German Centre for Cardiovascular Research

Impact of prediabetes and type 2 diabetes mellitus on cardiac function in the general population

Introduction

Prediabetes and type 2 diabetes mellitus (T2DM) are risk factors for heart failure (HF). The association of prediabetes and T2DM to different forms of functional left ventricular impairment and their impact on clinical outcome in the general population needs to be further investigated. In this context, little is known about the prevalences of prediabetes and different HF subtypes in the general population, especially in Europe.

Purpose

To investigate the prevalence and clinical impact of prediabetes and type 2 diabetes mellitus (T2DM) on functional cardiac disorder (FCD).

Methods

The participants of the Gutenberg Health Study sample (15,010 subjects, 35–74 years) were stratified in individuals with euglycaemia, prediabetes and T2DM based on clinical information and HbA1c level. FCD included asymptomatic systolic and diastolic dysfunction, symptomatic systolic and diastolic heart failure, asymptomatic diastolic dysfunction and preserved left ventricular ejection fraction (EF), asymptomatic diastolic dysfunction and reduced EF, asymptomatic preserved diastole and reduced EF, symptomatic heart failure with preserved EF (HFpEF) and symptomatic heart failure with reduced EF HFrEF). Using structured follow-up clinical outcome was assessed.

Results

Overall, 14,870 individuals were included in the present analysis. Among them, 9,426 individuals were categorized in the euglycaemia group, 4,128 participants had prediabetes and in 1,316 individuals T2DM was present. Prevalence of FCD increased from euglycaemia (19.6%) over prediabetes (33.3%) to T2DM (46.8%, p&lt;0.0001). Prevalence of symptomatic HF was increased in patients with T2DM (euglycaemia 2.8%, prediabetes 5.9%, T2DM 11.9%). T2DM was associated with reduced EF (β −0.63, 95% CI −0.99 to −0.26, P=0.00088) and elevated E/E' (β 0.08, 95% CI 0.06 to 0.10, P&lt;0.0001), whereas prediabetes was associated to elevated E/E' (β 0.02, 95% CI 0.01 to 0.03, P=0.0029). Prediabetes and T2DM revealed increased prevalences of FCD (13%, 18%), asymptomatic diastolic dysfunction with preserved EF (prediabetes: 14%, T2DM: 11%), symptomatic heart failure (prediabetes: 46%, T2DM: 70%) and HFpEF (prediabetes: 49%, T2DM: 82%). With prediabetes and T2DM all-cause mortality was elevated in presence and absence of FCD, only T2DM was also a risk factor for cardiovascular mortality with and without FCD. Within a 5-years follow-up, T2DM was an independent risk factor for the development of FCD, asymptomatic diastolic dysfunction with reduced ejection fraction, symptomatic heart failure and HFrEF. Prediabetes was not an independent risk factor for FCD.

Conclusions

In the general population, a high prevalence of asymptomatic FCD is present. Coexisting FCD and prediabetes as well as T2DM result in increased mortality elucidating the need for early detection and prevention of DM development, especially with regard to numerous asymptomatic people concerned. T2DM, but not prediabetes, is a risk factor for incident FCD.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): The Gutenberg Health Study is supported by the government of Rheinland-Pfalz (`Stiftung Rheinland-Pfalz für Innovation'), the research programmes `Wissen schafft Zukunft' and the Centre forTranslational Vascular Biology (CTVB) of the Johannes Gutenberg-University of Mainz, Germany, and its contract with Boehringer Ingelheim and Philips Medical Systems including an unrestricted grant forthe Gutenberg Health Study. P.S.W. and J.H.P. are funded by the Federal Ministry of Education and Research (BMBF 01EO1503). P.S.W. and T.M. are principal investigators of the German Center for Cardiovascular Research (DZHK). P.S.W. is principal investigator of the DIASyM research core (BMBF 161L0217A).

Mothers' and fathers' reflective functioning and its association with parenting behaviors and cortisol reactivity during a conflict interaction with their adolescent children

We assessed parental reflective functioning (PRF) with the Parent Development Interview-Revised and investigated its association with parenting behaviors, that is, autonomy support and psychological control (operationalized in terms of behaviors promoting and undermining autonomy relatedness), and stress responses (cortisol reactivity) during a parent-child conflict interaction task (Family Interaction Task). Participants were 40 mothers and 28 fathers, who took part in the study together with their adolescent children (N = 49). Mothers had significantly lower PRF and displayed more psychologically controlling behaviors in the interaction with their children than fathers. Rather than sex per se, high levels of PRF were the best predictors of autonomy support, whereas lower levels of PRF predicted more psychological control. Higher levels of PRF were also the best predictor for lower levels of parenting stress. Stress in the context of parenting was neither related to autonomy support nor to psychological control, which were best predicted by divorced family status and, for psychological control only, by parental sex. The findings point to the potential utility of interventions aimed at improving PRF, especially in divorced families, given its protective effect on parenting behaviors and stress in the context of parenting. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Vitreous Substitutes as Drug Release Systems

Vitreous substitutes are traditionally used to stabilize the retina after vitrectomy. In recent years, various approaches have been developed for using the vitreous substitute not only as a tamponade but also as a drug release system to tackle ocular diseases. This review provides an overview of the requirements for vitreous substitutes and discusses the current clinically applied as well as novel polymer-based vitreous substitutes as drug delivery systems, including their release mechanisms, efficiencies, challenges, and future perspectives.

A Theory-Informed, Personalized mHealth Intervention for Adolescents (Mobile App for Physical Activity): Development and Pilot Study

Background

Evidence suggests that physical activity (PA) during childhood and adolescence is crucial as it usually results in adequate PA levels in adulthood. Given the ubiquitous use of smartphones by adolescents, these devices may offer feasible means to reach young populations and deliver interventions aiming to increase PA participation and decrease sedentary time. To date, very few studies have reported smartphone-based interventions promoting PA for adolescents. In addition, most available fitness apps do not include the latest evidence-based content.

Objective

This paper described the systematic development of a behavior change, theory-informed Mobile App for Physical Activity intervention with personalized prompts for adolescents aged 16 to 18 years. The within-subject trial results provided the first evidence of the general effectiveness of the intervention based on the outcomes step count, sedentary time, and moderate to vigorous PA (MVPA) minutes. The effectiveness of the intervention component personalized PA prompt was also assessed.

Methods

A 4-week within-subject trial with 18 healthy adolescents aged 16 to 18 years was conducted (mean age 16.33, SD 0.57 years). After the baseline week, the participants used the Mobile App for Physical Activity intervention (Fitbit fitness tracker+app), which included a daily personalized PA prompt delivered via a pop-up notification. A paired 1-tailed t test was performed to assess the effectiveness of the intervention. Change-point analysis was performed to assess the effectiveness of a personalized PA prompt 30 and 60 minutes after prompt delivery.

Results

The results showed that the intervention significantly reduced sedentary time in adolescents during the first week of the trial (t₁₇=−1.79; P=.04; bootstrapped P=.02). This trend, although remaining positive, diminished over time. Our findings indicate that the intervention had no effect on metabolic equivalent of task–based MVPA minutes, although the descriptive increase may give reason for further investigation. Although the results suggested no overall change in heart rate–based MVPA minutes, the results from the change-point analyses suggest that the personalized PA prompts significantly increased heart rate per minute during the second week of the study (t₁₆=1.84; P=.04; bootstrapped P=.04). There were no significant increases in participants’ overall step count; however, the personalized PA prompts resulted in a marginally significant increase in step counts per minute in the second week of the study (t₁₇=1.35; P=.09; bootstrapped P=.05).

Conclusions

The results of the trial provide preliminary evidence of the benefit of the Mobile App for Physical Activity intervention for modest yet significant reductions in participants’ sedentary time and the beneficial role of personalized PA prompts. These results also provide further evidence of the benefits and relative efficacy of personalized activity suggestions for inclusion in smartphone-based PA interventions. This study provides an example of how to guide the development of smartphone-based mobile health PA interventions for adolescents.

Patterns of pulmonary function and mortality in chronic heart failure, results from the MyoVasc study

Background

Preclinical evidence suggests that pulmonary fibrosis due to left heart disease may represent end-organ damage in heart failure (HF). Vice versa, decreased pulmonary function is related to worsening of heart failure in the absence of obstructive airway pattern.

Purpose

This study investigated the relationship between patterns of pulmonary function (i.e. obstruction and restriction) and mortality in chronic HF.

Methods

For the present analysis data from the MyoVasc-study (N=3,289) were analysed. During a five-hour examination in the dedicated study center, systematic phenotyping was performed in a highly standardized setting. Chronic HF was defined as American Heart Association HF Stage C/D. Information on pulmonary function was assessed via body plethysmography (MasterScreen Body, Carefusion, Germany). Participants with forced expiratory ratio &lt;0.7 or COPD were categorized as obstructive, while restriction was defined as reduction in total lung capacity. Information on vital status was obtained via registration offices.

Results

The analysis sample comprised 1,509 individuals with chronic heart failure and information on pulmonary function, of whom 286 had HF with reduced ejection fraction (HFrEF), 559 HF with preserved ejection fraction (HFpEF), and 333 HFpEFborderline. The mean age was 64.6±11.3 years, 38.7% were female. In the sample 124 subjects had pulmonary restriction and 400 individuals had an obstruction. During a median time to follow up of 3.70 (inter quartile range 1.25 to 4.00) years, death occurred in 170 individuals. Among clusters of pulmonary function most participants died in the restriction group (25.0%), followed by pulmonary obstruction (12.2%) and normal pulmonary function (7.3%, P for trend &lt;0.001). Cox- regression analysis adjusted for age, sex and height revealed pulmonary restriction (hazard ratio (HR) 3.00 [95% confidence interval 2.04–4.42], P&lt;0.001] and obstruction (HR 1.61 [1.11–2.35], P=0.01) as predictors of all-cause death. After additional controlling for traditional cardiovascular risk factors and the clinical profile only pulmonary restriction remained an independent predictor of mortality (HRrestriction 2.12 [1.50–3.43]; P=0.002; HRobstruction 1.35 [0.91–2.00]; P=0.10). Among HF phenotypes obstruction was only in individuals with HFpEF an independent predictor of all-cause death (HRHFpEF 2.60 [1.29–5.23]; P=0.007; HRHFpEFborderline 1.58 [0.70–3.57]; P=0.27; HRHFrEF 0.96 [0.52–1.78]; P=0.90), while pulmonary restriction was found to be predictive for death only in subjects with HFpEFborderline (HRHFpEF 2.15 [0.70–6.64]; P=0.18; HRHFpEFborderline: HR 5.47 [2.56–11.68]; P&lt;0.001; HRHFrEF 1.74 [0.88–3.46]; P=0.11)

Conclusion

In chronic heart failure, pulmonary restriction was a stronger predictor of mortality than obstructive airway pattern. The present analysis supports the hypothesis of pulmonary fibrosis as end-organ damage in HF, and may potentially represent a therapeutic target.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): German Center for Cardiovascular Research (DZHK)

Tubulin-folding cofactor E deficiency is associated with vascular dysfunction and endoplasmatic reticulum stress of vascular smooth muscle cells

Introduction

Endothelial function assessed via flow mediated dilatation (FMD) has shown to predict risk in individuals with established cardiovascular diseases, whereas its predictive value is uncertain in the setting primary prevention.

Purpose

The aim of the current work was to discover and evaluate novel mediators of vascular dysfunction in the general population and in conditional knock-out transgenic animal models.

Methods

In order to identify novel targets that were negatively correlated with FMD and investigate their contribution in vascular function, a Genome Wide Association Study (GWAS) of 5,000 participants was performed and subsequently immune cell-, endothelial- and vascular smooth muscle cell (VSMCs)-targeted conditional knockout mouse models were generated and characterized.

Results

GWAS analysis revealed that single nucleotide polymorphisms (SNPs) in the tubulin folding cofactor E (TBCE) gene were negatively correlated with FMD and TBCE expression in the peripheral blood mononuclear cells (PBMCs). Myelomonocytic cell-targeted TBCE deficiency did not lead to any vascular dysfunction in vivo in the LysM+Cre+/−TBCEfl/fl mice. Endothelial-targeted TBCE deficiency led to an NLR family pyrin domain containing 3 (NLRP3)-dependent activation of the inflammasome in the endothelial cells of Tie2-ERT2Cre+/−TBCEfl/fl mice. Importantly, VSMC-targeted TBCE deficiency was associated with endothelial dysfunction, increased aortic wall thickness and endoplasmatic reticulum (ER) stress-mediated VSMC hyperproliferation in vivo (SMMHC-ERT2Cre+/−TBCEfl/fl), paralleled by calnexin upregulation. Administration of the blood pressure hormone angiotensin II exacerbated the vascular dysfunction and phenotype. Administration of the ER stress modulator tauroursodeoxycholic acid to the SMMHC-ERT2Cre+/−TBCEfl/fl mice reversed vascular dysfunction, paralleled by induction of Raptor/Beclin-1-dependent autophagy both in vitro and in vivo.

Conclusion

TBCE and tubulin homeostasis in the vascular musculature seem to be novel markers of vascular function and represent a new druggable target for the treatment of ER-stress-mediated vascular dysfunction.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): This work was supported by grants of the German Federal Ministry for Education and Research (BMBF01EO1003 and BMBF01EO1503), the DFG Major Research Instrumentation Programme (DFG INST 371/47-1 FUGG) as well as the Boehringer Ingelheim Foundation. PW received funds from the German Research Foundation in support of his work (DFG WE4361-4-1 and WE 4361/7-1). KS, TM and PW are PIs of the DZHK.

Development of heart failure in long-term survivors of childhood cancer: results from the cvss study

Background

Long-term survivors of childhood cancer (CCS) are at increased risk for cardiovascular sequelae, including heart failure (HF) as the largest non-malignant contributor to excess death. Yet, little is known about the risk factors, mechanisms of cardiac dysfunction and prevalence of different stages of HF in these patients.

Purpose

To investigate the development and prevalence of HF phenotypes in CCS compared to the general population.

Methods

The CVSS study is a prospective single-center cohort study investigating cardiovascular sequelae of CCS. Patients were eligible for the study when they were diagnosed with a neoplasia according to the International Classification of Childhood Cancer (ICCC 3) at an age prior to 15 years between 1980 and 1990, survived more than five years after initial cancer diagnosis and received antineoplastic treatment. Between 2013 and 2016, study individuals underwent a comprehensive, standardized clinical investigation in the CVSS cohort study including echocardiographic examination. HF was categorized as stages A to D according to current HF guidelines of the American Heart Association (AHA). A population-based sample free of cancer (age- and sex matched) serves as control group.

Results

From 1,002 individuals, all CCS with history of chemo- or radiotherapy and no subsequent neoplasia (n=877) were included (mean age 34.2 (±5.5) years, 44.7% (N=392) female). Age at diagnosis was 6.28 years (±4.24) and the mean interval from the date of diagnosis of cancer to the date of completion of baseline examination 28.5±3.2 years. Based on echocardiographic examination, clinical data and biomarker assessment, 26.6% of CCS were diagnosed with HF stage A, 21.1% with HF stage B and 2.1% with symptomatic HF, i.e. HF stage C/D. Importantly, prevalence of different HF stages varied strongly by specific tumor history. Compared to the population, the prevalence ratio (PR) was 1.16 [95% confidence interval 1.02/1.31] for stage A HF and 1.91 [1.63/2.23] for the composite of stage B to D HF in an age- and sex-adjusted Poisson regression model. Multivariable linear regression with the systolic marker left ventricular ejection fraction as dependent variable and adjustment for tumor entities, age, sex, and cardiovascular risk factors (CVRF) revealed a lower EF in patients with history of bone tumors (β −6.0 [−8.1/−3.0]), soft tissue sarcoma (β −2.2 [−4.1/−0.35]), leukemia (β −0.84 [−1.8/0.08]) and renal tumors (β −1.8 [−4.0/0.27]) compared to the population. In contrast, the same model for the diastolic marker E/E', showed an association only with CVRF, but not with tumor entities.

Conclusion

The prevalence of stage B to D HF was significantly higher among long-term CCS in the 3rd to 5th age decade compared to the population and varied strongly by tumor entity. Systolic dysfunction was primarily associated with history of tumor entities, whereas diastolic dysfunction was associated with the higher burden of CVRF in CCS.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This study is funded by the Deutsche Forschungsgemeinschaft (DFG) (SP 1381/2-1&2, FA 1038/2-1&2, WI 3881/2-1&2)

Interoception in preschoolers: New insights into its assessment and relations to emotion regulation and stress

Interoception may play an important role for emotion regulation and stress, thereby affecting mental health in children and adults. Yet, little is known on interoception in preschool children. Therefore, we investigated interoceptive accuracy using the adapted Jumping Jack Paradigm (JJP) and its relationship with emotion regulation and stress. In Study I, 40 preschoolers completed the JJP and an emotion regulation task, demonstrating a positive relationship between interoceptive accuracy and emotion regulation at trend level (R² = 0.231, p = .023; β = .278, p = .073). In Study II, 31 preschoolers completed the adapted JJP before and after an acute laboratory stress test. Higher total cortisol output following acute stress induction was associated with reduced interoceptive accuracy (r = -0.670, p = .017). Extending earlier findings in adults and school-children, the relationship of interoceptive accuracy with emotion regulation and stress highlights the importance to investigate interoception in early childhood.

Droplet-based vitrification of adherent human induced pluripotent stem cells on alginate microcarrier influenced by adhesion time and matrix elasticity

The gold standard in cryopreservation is still conventional slow freezing of single cells or small aggregates in suspension, although major cell loss and limitation to non-specialised cell types in stem cell technology are known drawbacks. The requirement for rapidly available therapeutic and diagnostic cell types is increasing constantly. In the case of human induced pluripotent stem cells (hiPSCs) or their derivates, more sophisticated cryopreservation protocols are needed to address this demand. These should allow a preservation in their physiological, adherent state, an efficient re-cultivation and upscaling upon thawing towards high-throughput applications in cell therapies or disease modelling in drug discovery. Here, we present a novel vitrification-based method for adherent hiPSCs, designed for automated handling by microfluidic approaches and with ready-to-use potential e.g. in suspension-based bioreactors after thawing. Modifiable alginate microcarriers serve as a growth surface for adherent hiPSCs that were cultured in a suspension-based bioreactor and subsequently cryopreserved via droplet-based vitrification in comparison to conventional slow freezing. Soft (0.35%) versus stiff (0.65%) alginate microcarriers in concert with adhesion time variation have been examined. Findings revealed specific optimal conditions leading to an adhesion time and growth surface (matrix) elasticity dependent hypothesis on cryo-induced damaging regimes for adherent cell types. Deviations from the found optimum parameters give rise to membrane ruptures assessed via SEM and major cell loss after adherent vitrification. Applying the optimal conditions, droplet-based vitrification was superior to conventional slow freezing. A decreased microcarrier stiffness was found to outperform stiffer material regarding cell recovery, whereas the stemness characteristics of rewarmed hiPSCs were preserved.

Ethanol inactivation of orthonairoviruses in ixodid ticks

Ixodid ticks represent vectors and reservoirs for a broad range of zoonotic pathogens. Collected ticks from field studies are therefore usually stored in ethanol, which in higher concentrations effectively inactivates most of the known tick-borne pathogens. Although commonly practiced as gold standard for inactivation, hardly any scientific data demonstrate that ethanol sufficiently penetrates the comparatively thick cuticula of ticks. Therefore, Amblyomma hebraeum tick pools were stored for 21 days in ethanol (96%). Afterwards, the ethanol was removed and the ticks were homogenized. Quantitative ¹H-NMR spectroscopic analysis was applied to determine the residual concentration of ethanol inside the ticks. ¹H-NMR spectroscopic analysis revealed that ethanol constituted 28.3-42.6 mg of the total weight of three ticks in the pools (89.9-121.5 mg). In addition, the low-pathogenic Hazara orthonairovirus (HAZV) was used as a cell culture model for this study. The virus was exposed to ethanol concentrations between 0 and 60% and incubated under various temperature conditions for four time periods. Afterwards, the residual virus infectivity was determined by titration. Following ethanol exposure, HAZV did not grow in cells after 9 h of exposure to an ethanol concentration of 25%. These results demonstrate an extremely low ethanol resistance of the virus, which was generally in line with previously reported ethanol inactivation data for Crimean-Congo hemorrhagic fever orthonairovirus (CCHFV). After prolonged storage and impregnation, comparable ethanol concentrations are achieved in the ticks, indicating the suitability of this inactivation method also for Bunyaviruses in ticks. At the very least, a massive virus inactivation can be assumed. Definitive proof of virus inactivation would require a bioassay of ethanol-treated infected ticks under appropriate biosafety conditions.

Cleavage plane after liquid-bubble preparation of Descemet's membrane

PURPOSE

To investigate the ultrastructure of the cleavage plane of human cornea after liquid-bubble-prepared tissue for Descemet's membrane endothelial keratoplasty (DMEK).

METHODS

Experimental study with scanning electron microscopy (SEM) and block-face SEM of 18 corneal specimens. Fresh human research donor corneoscleral discs (n = 12) were prepared with liquid-bubble technique or examined as untreated controls (n = 3). In addition, Descemet's membrane samples, n = 3, were obtained in DMEK surgery.

RESULTS

The cleavage plane after liquid-bubble Descemet's membrane (DM) preparation was consistently located between interfacial matrix and posterior stromal collagen lamellae, providing a largely smooth surface exposing the amorphous interfacial zone without any significant amounts of adherent stromal remnants. No demarcation of a distinct pre-DM layer could be detected.

CONCLUSION

The DMEK graft preparation performed by liquid-bubble technique showed a smooth cleavage plane and could not reveal any demarcation of a distinct pre-DM layer.

On the construct validity of interoceptive accuracy based on heartbeat counting: Cardiovascular determinants of absolute and tilt-induced change scores

Interoceptive accuracy (IAcc) as assessed with the heartbeat counting task (IAcc_HBCT) may be affected by a range of factors including (1.) the ability to adequately detect cardiac signals, indicated by IAcc in a heartbeat discrimination task (IAcc_HBDT), (2.) cardiac signal properties, affected by sympathetic and parasympathetic tone, and (3.) non-interoceptive processes, including time estimation accuracy (TEAcc). In the current study we investigated the contribution of these factors to absolute and Δ IAcc_HBCT scores, induced by passive head-up and head-down tilt in 49 healthy individuals. A set of hierarchical regression models showed IAcc_HBDT scores as the strongest and, across different orthostatic (tilt) conditions, most stable (positive) predictor of absolute and Δ IAcc_HBCT scores. Neither indicators of cardiac signal properties (except for HR in head-down-tilt), nor TEAcc predicted absolute or Δ IAcc_HBCT scores. These findings support the convergent and discriminant validity of absolute and Δ IAcc_HBCT scores.

Selective Large-Area Retinal Pigment Epithelial Removal by Microsecond Laser in Preparation for Cell Therapy

Purpose

Cell therapy is a promising treatment for retinal pigment epithelium (RPE)-associated eye diseases such as age-related macular degeneration. Herein, selective microsecond laser irradiation targeting RPE cells was used for minimally invasive, large-area RPE removal in preparation for delivery of retinal cell therapeutics.

Methods

Ten rabbit eyes were exposed to laser pulses 8, 12, 16, and 20 µs in duration (wavelength, 532 nm; top-hat beam profile, 223 × 223 µm²). Post-irradiation retinal changes were assessed with fluorescein angiography (FA), indocyanine green angiography (ICGA), and optical coherence tomography (OCT). RPE viability was evaluated with an angiographic probit model. Following vitrectomy, a subretinal injection of balanced salt solution was performed over a lasered (maximum 13.6 mm2) and untreated control area. Bleb retinal detachment (bRD) morphology was then evaluated by intraoperative OCT.

Results

Within 1 hour after irradiation, laser lesions showed FA and ICGA leakage. OCT revealed that large-area laser damage was limited to the RPE. The angiographic median effective dose irradiation thresholds (ED50) were 45 µJ (90 mJ/cm2) at 8 µs, 52 µJ (104 mJ/cm2) at 12 µs, 59 µJ (118 mJ/cm2) at 16 µs, and 71 µJ (142 mJ/cm2) at 20 µs. Subretinal injection over the lasered area resulted in a controlled, shallow bRD rise, whereas control blebs were convex in shape, with less predictable spread.

Conclusions

Large-area, laser-based removal of host RPE without visible photoreceptor damage is possible and facilitates surgical retinal detachment.

Translational Relevance

Selective microsecond laser-based, large-area RPE removal prior to retinal cell therapy may reduce iatrogenic trauma.

Lithium-salt-based deep eutectic solvents: Importance of glass formation and rotation-translation coupling for the ionic charge transport

Lithium-salt-based deep eutectic solvents, where the only cation is Li⁺, are promising candidates as electrolytes in electrochemical energy-storage devices, such as batteries. We have performed broadband dielectric spectroscopy on three such systems, covering a broad temperature and dynamic range that extends from the low-viscosity liquid around room temperature down to the glassy state approaching the glass-transition temperature. We detect a relaxational process that can be ascribed to dipolar reorientational dynamics and exhibits the clear signatures of glassy freezing. We find that the temperature dependence of the ionic dc conductivity and its room-temperature value also are governed by the glassy dynamics of these systems, depending, e.g., on the glass-transition temperature and fragility. Compared to the previously investigated corresponding systems, containing choline chloride instead of a lithium salt, both the reorientational and ionic dynamics are significantly reduced due to variations in the glass-transition temperature and the higher ionic potential of the lithium ions. These lithium-based deep eutectic solvents partly exhibit significant decoupling of the dipolar reorientational and the ionic translational dynamics and approximately follow a fractional Debye-Stokes-Einstein relation, leading to an enhancement of the dc conductivity, especially at low temperatures. The presented results clearly reveal the importance of decoupling effects and of the typical glass-forming properties of these systems for the technically relevant room-temperature conductivity.

Gastric interoception and gastric myoelectrical activity in bulimia nervosa and binge-eating disorder

OBJECTIVE

Identifying factors that control food intake is crucial to the understanding and treatment of eating disorders characterized by binge eating. In healthy individuals, stomach distension plays an important role in the development of satiation, but gastric sensations might be overridden in binge eating. The present study investigated the perception of gastric signals (i.e., gastric interoception) and gastric motility in patients experiencing binge-eating episodes, that is, bulimia nervosa (BN) and binge-eating disorder (BED).

METHOD

Twenty-nine patients with BN or BED (ED group) and 32 age-, sex-, and BMI-matched healthy controls (HC group) participated in the study. The onset of satiation and stomach fullness were assessed using a novel 2-step water load test (WLT-II). Gastric myoelectrical activity (GMA) was measured by electrogastrography (EGG) before and after ingestion of noncaloric water.

RESULTS

Individuals in the ED group drank significantly more water until reporting satiation during the WLT-II. The percentage of normal gastric myoelectrical power was significantly smaller in the ED group compared to HC, and negatively related to the number of objective binge-eating episodes per week in patients with BN or BED. Power in the bradygastria range was greater in ED than in HC participants.

DISCUSSION

Patients with EDs have a delayed response to satiation compared to HC participants, together with abnormal GMA. Repeated binge-eating episodes may induce disturbances to gastric motor function.

Detection of Crimean-Congo hemorrhagic fever virus in blood-fed Hyalomma ticks collected from Mauritanian livestock

Background

Crimean-Congo hemorrhagic fever virus (CCHFV) belongs to the genus Orthonairovirus (Nairovididae) and is a (re)emerging tick-borne pathogen. It is endemic in most parts of Africa, Asia and southern Europe, and can cause severe hemorrhagic symptoms in humans, with high fatality rates (5–30%).

Methods

Hyalomma ticks were collected from four different livestock herds (cattle and camels) in Mauritania in 2018. The tick species were determined morphologically and confirmed molecularly by using the cytochrome oxidase 1 gene marker. For the detection of CCHFV, ticks were tested individually by one-step multiplex real-time reverse-transcriptase quantitative polymerase chain reaction. The small segment of all positive samples was sequenced to determine the CCHFV genotype.

Results

In total, 39 of the 1523 ticks (2.56%) collected from 63 cattles and 28 camels tested positive for CCHFV. Three Hyalomma species were identified. Hyalomma rufipes had the largest proportion of positivity (5.67%; 16/282), followed by Hyalomma dromedarii (1.89%; 23/1214). No Hyalomma impeltatum tested positive (0%; 0/21). Positive ticks were found in only six out of 91 host animals. Viral sequence analysis revealed the presence of two different CCHFV lineages (Africa I and Africa III).

Conclusions

In this study, 2.56% of Hyalomma ticks collected from camels and cattle in Mauritania tested positive for CCHFV. However, the true prevalence of CCHFV in unfed ticks may be lower, as a considerable number of ticks may have been passively infected during blood-feeding by co-feeding ticks or due to viremia of the host. The results indicate the need to track the actual area of circulation of this virus.

Graphic Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-021-04819-x.

Novel vitreous substitutes: the next frontier in vitreoretinal surgery

PURPOSE OF REVIEW

After removing the native vitreous during vitreoretinal surgery, an adequate substitute is required to ensure homeostasis of the eye. Current clinically used endotamponades (silicone oil, gases, semifluorinated alkanes) are effective in promoting retinal reattachment, but lead to complications such as emulsification, prolonged inflammation, blurred vision, raised intraocular pressure, cataract formation or the need for revision surgery. The aim of this review is to provide an update on novel vitreous substitutes with a focus on polymer-based systems.

RECENT FINDINGS

Polymeric hydrogels provide favourable properties such as high water content, optical transparency, suitable refractive indices and densities, adjustable rheological properties, injectability, biocompatibility and their ability to tamponade the retina via viscosity and swelling pressure, comparable to the native human vitreous body. Here, vitreous replacement strategies can be divided into chemically or physically crosslinked hydrogel systems that are applied as preformed or in-situ gelling matrices.

SUMMARY

Several hydrogel-based vitreous substitutes have already been positively evaluated in preclinical tests and have the potential to enter the clinical phase soon.