Assessing Stress Induced by Fluid Shifts and Reduced Cerebral Clearance during Robotic-Assisted Laparoscopic Radical Prostatectomy under Trendelenburg Positioning (UroTreND Study)

In addition to general anesthesia and mechanical ventilation, robotic-assisted laparoscopic radical prostatectomy (RALP) necessitates maintaining a capnoperitoneum and placing the patient in a pronounced downward tilt (Trendelenburg position). While the effects of the resulting fluid shift on the cardiovascular system seem to be modest and well tolerated, the effects on the brain and the blood-brain barrier have not been thoroughly investigated. Previous studies indicated that select patients showed an increase in the optic nerve sheath diameter (ONSD), detected by ultrasound during RALP, which suggests an elevation in intracranial pressure. We hypothesize that the intraoperative fluid shift results in endothelial dysfunction and reduced cerebral clearance, potentially leading to transient neuronal damage. This prospective, monocentric, non-randomized, controlled clinical trial will compare RALP to conventional open radical prostatectomy (control group) in a total of 50 subjects. The primary endpoint will be the perioperative concentration of neurofilament light chain (NfL) in blood using single-molecule array (SiMoA) as a measure for neuronal damage. As secondary endpoints, various other markers for endothelial function, inflammation, and neuronal damage as well as the ONSD will be assessed. Perioperative stress will be evaluated by questionnaires and stress hormone levels in saliva samples. Furthermore, the subjects will participate in functional tests to evaluate neurocognitive function. Each subject will be followed up until discharge. Conclusion: This trial aims to expand current knowledge as well as to develop strategies for improved monitoring and higher safety of patients undergoing RALP. The trial was registered with the German Clinical Trials Register DRKS00031041 on 11 January 2023.

Dietary habits, traveling and the living situation potentially influence the susceptibility to SARS-CoV-2 infection: results from healthcare workers participating in the RisCoin Study

PURPOSE

To explore occupational and non-occupational risk and protective factors for the coronavirus disease 2019 (COVID-19) in healthcare workers (HCWs).

METHODS

Serum specimens and questionnaire data were obtained between October 7 and December 16, 2021 from COVID-19-vaccinated HCWs at a quaternary care hospital in Munich, Germany, and were analyzed in the RisCoin Study.

RESULTS

Of 3,696 participants evaluated, 6.6% have had COVID-19 at least once. Multivariate logistic regression analysis identified working in patient care occupations (7.3% had COVID-19, 95% CI 6.4-8.3, Pr = 0.0002), especially as nurses, to be a potential occupation-related COVID-19 risk factor. Non-occupational factors significantly associated with high rates of the disease were contacts to COVID-19 cases in the community (12.8% had COVID-19, 95% CI 10.3-15.8, Pr < 0.0001), being obese (9.9% had COVID-19, 95% CI 7.1-13.5, Pr = 0.0014), and frequent traveling abroad (9.4% had COVID-19, 95% CI 7.1-12.3, Pr = 0.0088). On the contrary, receiving the basic COVID-19 immunization early during the pandemic (5.9% had COVID-19, 95% CI 5.1-6.8, Pr < 0.0001), regular smoking (3.6% had COVID-19, 95% CI 2.1-6.0, Pr = 0.0088), living with the elderly (3.0% had COVID-19, 95% CI 1.0-8.0, Pr = 0.0475), and frequent consumption of ready-to-eat meals (2.6% had COVID-19, 95% CI 1.1-5.4, Pr = 0.0045) were non-occupational factors potentially protecting study participants against COVID-19.

CONCLUSION

The newly discovered associations between the living situation, traveling as well as dietary habits and altered COVID-19 risk can potentially help refine containment measures and, furthermore, contribute to new mechanistic insights that may aid the protection of risk groups and vulnerable individuals.

Questionnaire-based study of COVID-19 vaccination induced headache: evidence of clusters of adverse events

BACKGROUND

The adverse events (AEs) after a Coronavirus disease 2019 (Covid-19) Pfizer-Biotech mRNA vaccination present a medical and epidemiological issue of increasing interest. Headache is the most frequent neurological adverse effect and generally the third most common adverse event after a Covid-19 vaccination, but only a few studies focus on the link between headache and other AEs after vaccination. This study aims to investigate the correlation between headaches and Covid-19 vaccination, as well as the possible links between headaches and other AEs after Covid-19 vaccination, thereby helping the management of AEs and avoiding further occurrences.

METHODS

This study is based on a published questionnaire survey of 1,402 healthcare workers. Our study focused on the 5 questions including 12 AEs and headaches extracted from the questionnaire post the first and second Covid-19 vaccination. The severity of the 12 AEs and headaches could be classified by the participants on a five-step scale: "Not at all", "Little", "Average", "Quite", and "Very" (abbreviated as "N", "L", "A", "Q", "V"). We used the Bowker test to study the comparison of headache severity, indicated on a 5-point Likert scale between the first and second vaccinations. We applied an ordinal logistic regression to the 5 categories with headache severity serving as the dependent variable and the ratings of the other 12 AEs serving as the independent variable to further explore to what extent the severity of the 12 AEs is associated with the severity of headaches. Receiver Operating Characteristic (ROC) analysis was conducted to evaluate the predictive value of the ratings of the 12 AEs to headache severity.

RESULTS

We found that participants rated their headaches as more severe after the second vaccination, and participants who reported experiencing fatigue, flu-like symptoms, pain at the injection site, known tension-type headache, fever, dizziness/balance problems and known migraine are associated with headache symptoms.

CONCLUSIONS

There are clusters of headache-associated AEs post Covid-19 vaccination. The association of various AEs with headaches may be due to similar causative mechanisms.

How are cell and tissue structure and function influenced by gravity and what are the gravity perception mechanisms?

Progress in mechanobiology allowed us to better understand the important role of mechanical forces in the regulation of biological processes. Space research in the field of life sciences clearly showed that gravity plays a crucial role in biological processes. The space environment offers the unique opportunity to carry out experiments without gravity, helping us not only to understand the effects of gravitational alterations on biological systems but also the mechanisms underlying mechanoperception and cell/tissue response to mechanical and gravitational stresses. Despite the progress made so far, for future space exploration programs it is necessary to increase our knowledge on the mechanotransduction processes as well as on the molecular mechanisms underlying microgravity-induced cell and tissue alterations. This white paper reports the suggestions and recommendations of the SciSpacE Science Community for the elaboration of the section of the European Space Agency roadmap "Biology in Space and Analogue Environments" focusing on "How are cells and tissues influenced by gravity and what are the gravity perception mechanisms?" The knowledge gaps that prevent the Science Community from fully answering this question and the activities proposed to fill them are discussed.

Palmer Station, Antarctica: A ground-based spaceflight analog suitable for validation of biomedical countermeasures for deep space missions

Astronauts are known to exhibit a variety of immunological alterations during spaceflight including changes in leukocyte distribution and plasma cytokine concentrations, a reduction in T-cell function, and subclinical reactivation of latent herpesviruses. These alterations are most likely due to mission-associated stressors including circadian misalignment, microgravity, isolation, altered nutrition, and increased exposure to cosmic radiation. Some of these stressors may also occur in terrestrial situations. This study sought to determine if crewmembers performing winterover deployment at Palmer Station, Antarctica, displayed similar immune alterations. The larger goal was to validate a ground analog suitable for the evaluation of countermeasures designed to protect astronauts during future deep space missions. For this pilot study, plasma, saliva, hair, and health surveys were collected from Palmer Station, Antarctica, winterover participants at baseline, and at five winterover timepoints. Twenty-six subjects consented to participate over the course of two seasons. Initial sample processing was performed at Palmer, and eventually stabilized samples were returned to the Johnson Space Center for analysis. A white blood cell differential was performed (real time) using a fingerstick blood sample to determine alterations in basic leukocyte subsets throughout the winterover. Plasma and saliva samples were analyzed for 30 and 13 cytokines, respectively. Saliva was analyzed for cortisol concentration and three latent herpesviruses (DNA by qPCR), EBV, HSV1, and VZV. Voluntary surveys related to general health and adverse clinical events were distributed to participants. It is noteworthy that due to logistical constraints caused by COVID-19, the baseline samples for each season were collected in Punta Arenas, Chile, after long international travel and during isolation. Therefore, the Palmer pre-mission samples may not reflect a true normal 'baseline'. Minimal alterations were observed in leukocyte distribution during winterover. The mean percentage of monocyte concentration elevated at one timepoint. Plasma G-CSF, IL1RA, MCP-1, MIP-1β, TNFα, and VEGF were decreased during at least one winterover timepoint, whereas RANTES was significantly increased. No statistically significant changes were observed in mean saliva cytokine concentrations. Salivary cortisol was substantially elevated throughout the entire winterover compared to baseline. Compared to shedding levels observed in healthy controls (23%), the percentage of participants who shed EBV was higher throughout all winterover timepoints (52-60%). Five subjects shed HSV1 during at least one timepoint throughout the season compared to no subjects shedding during pre-deployment. Finally, VZV reactivation, common in astronauts but exceptionally rare in ground-based stress analogs, was observed in one subject during pre-deployment and a different subject at WO2 and WO3. These pilot data, somewhat influenced by the COVID-19 pandemic, do suggest that participants at Palmer Station undergo immunological alterations similar to, but likely in reduced magnitude, as those observed in astronauts. We suggest that winterover at Palmer Station may be a suitable test analog for spaceflight biomedical countermeasures designed to mitigate clinical risks for deep space missions.

Endocannabinoids, endocannabinoid-like compounds and cortisone in head hair of health care workers as markers of stress and resilience during the early COVID-19 pandemic

The pandemic caused by SARS-CoV-2 impacted health systems globally, creating increased workload and mental stress upon health care workers (HCW). During the first pandemic wave (March to May 2020) in southern Germany, we investigated the impact of stress and the resilience to stress in HCW by measuring changes in hair concentrations of endocannabinoids, endocannabinoid-like compounds and cortisone. HCW (n = 178) recruited from multiple occupation and worksites in the LMU-University-Hospital in Munich were interviewed at four interval visits to evaluate mental stress associated with the COVID-19 pandemic. A strand of hair of up to 6 cm in length was sampled once in May 2020, which enabled retrospective individual stress hormone quantifications during that aforementioned time period. Perceived anxiety and impact on mental health were demonstrated to be higher at the beginning of the COVID-19 pandemic and decreased significantly thereafter. Resilience was stable over time, but noted to be lower in women than in men. The concentrations of the endocannabinoid anandamide (AEA) and the structural congeners N-palmitoylethanolamide (PEA), N-oleoylethanolamide (OEA) and N-stearoylethanolamide (SEA) were noted to have decreased significantly over the course of the pandemic. In contrast, the endocannabinoid 2-arachidonoylglycerol (2-AG) levels increased significantly and were found to be higher in nurses, laboratory staff and hospital administration than in physicians. PEA was significantly higher in subjects with a higher resilience but lower in subjects with anxiety. SEA was also noted to be reduced in subjects with anxiety. Nurses had significantly higher cortisone levels than physicians, while female subjects had significant lower cortisone levels than males. Hair samples provided temporal and measurable objective psychophysiological-hormonal information. The hair endocannabinoids/endocannabinoid-like compounds and cortisone correlated to each other and to professions, age and sex quite differentially, relative to specific periods of the COVID-19 pandemic.

Monitoring functional immune responses with a cytokine release assay: ISS flight hardware design and experimental protocol for whole blood cultures executed under microgravity conditions

Introduction: Long-term space missions trigger a prolonged neuroendocrine stress response leading to immune system dysregulation evidenced by susceptibility to infections, viral reactivation, and skin irritations. However, due to existing technical constraints, real-time functional immune assessments are not currently available to crew inflight. The in vitro cytokine release assay (CRA) has been effectively employed to study the stimulated cytokine response of immune cells in whole blood albeit limited to pre- and post-flight sessions. A novel two-valve reaction tube (RT) has been developed to enable the execution of the CRA on the International Space Station (ISS). Methods: In a comprehensive test campaign, we assessed the suitability of three materials (silicone, C-Flex, and PVC) for the RT design in terms of biochemical compatibility, chemical stability, and final data quality analysis. Furthermore, we thoroughly examined additional quality criteria such as safety, handling, and the frozen storage of antigens within the RTs. The validation of the proposed crew procedure was conducted during a parabolic flight campaign. Results: The selected material and procedure proved to be both feasible and secure yielding consistent and dependable data outcomes. This new hardware allows for the stimulation of blood samples on board the ISS, with subsequent analysis still conducted on the ground. Discussion: The resultant data promises to offer a more accurate understanding of the stress-induced neuroendocrine modulation of immunity during space travel providing valuable insights for the scientific community. Furthermore, the versatile nature of the RT suggests its potential utility as a testing platform for various other assays or sample types.

ACE2-independent SARS-CoV-2 virus entry through cell surface GRP78 on monocytes - evidence from a translational clinical and experimental approach

BACKGROUND

SARS-CoV-2 infects host cells via an ACE2/TMPRSS2 entry mechanism. Monocytes and macrophages, which play a key role during severe COVID-19 express only low or no ACE2, suggesting alternative entry mechanisms in these cells. In silico analyses predicted GRP78, which is constitutively expressed on monocytes and macrophages, to be a potential candidate receptor for SARS-CoV-2 virus entry.

METHODS

Hospitalized COVID-19 patients were characterized regarding their pro-inflammatory state and cell surface GRP78 (csGRP78) expression in comparison to healthy controls. RNA from CD14+ monocytes of patients and controls were subjected to transcriptome analysis that was specifically complemented by bioinformatic re-analyses of bronchoalveolar lavage fluid (BALF) datasets of COVID-19 patients with a focus on monocyte/macrophage subsets, SARS-CoV-2 infection state as well as GRP78 gene expression. Monocyte and macrophage immunohistocytochemistry on GRP78 was conducted in post-mortem lung tissues. SARS-CoV-2 spike and GRP78 protein interaction was analyzed by surface plasmon resonance, GST Pull-down and Co-Immunoprecipitation. SARS-CoV-2 pseudovirus or single spike protein uptake was quantified in csGRP78high THP-1 cells.

FINDINGS

Cytokine patterns, monocyte activation markers and transcriptomic changes indicated typical COVID-19 associated inflammation accompanied by upregulated csGRP78 expression on peripheral blood and lung monocytes/macrophages. Subsequent cell culture experiments confirmed an association between elevated pro-inflammatory cytokine levels and upregulation of csGRP78. Interaction of csGRP78 and SARS-CoV-2 spike protein with a dissociation constant of KD = 55.2 nM was validated in vitro. Infection rate analyses in ACE2low and GRP78high THP-1 cells showed increased uptake of pseudovirus expressing SARS-CoV-2 spike protein.

INTERPRETATION

Our results demonstrate that csGRP78 acts as a receptor for SARS-CoV-2 spike protein to mediate ACE2-independent virus entry into monocytes.

FUNDING

Funded by the Sino-German-Center for Science Promotion (C-0040) and the Germany Ministry BMWi/K [DLR-grant 50WB1931 and RP1920 to AC, DM, TW].

A prospective longitudinal cohort study on risk factors for COVID-19 vaccination failure (RisCoin): methods, procedures and characterization of the cohort

The primary objective of the RisCoin study was to investigate the interplay of genetic, metabolic, and lifestyle factors as well as stress levels on influencing the humoral immune response after at least two COVID-19 vaccinations, primarily with mRNAs, and the risk of SARS-CoV-2 breakthrough infections during follow-up. Here, we describe the study design, procedures, and study population. RisCoin is a prospective, monocentric, longitudinal, observational cohort study. Between October and December 2021, 4515 participants with at least two COVID-19 vaccinations, primarily BNT162b2 and mRNA-1273, were enrolled at the LMU University Hospital of Munich, thereof > 4000 healthcare workers (HCW), 180 patients with inflammatory bowel disease under immunosuppression, and 119 patients with mental disorders. At enrollment, blood and saliva samples were collected to measure anti-SARS-CoV-2 antibodies, their neutralizing capacity against Omicron-BA.1, stress markers, metabolomics, and genetics. To ensure the confidential handling of sensitive data of study participants, we developed a data protection concept and a mobile application for two-way communication. The application allowed continuous data reporting, including breakthrough infections by the participants, despite irreversible anonymization. Up to 1500 participants attended follow-up visits every two to six months after enrollment. The study gathered comprehensive data and bio-samples of a large representative HCW cohort and two patient groups allowing analyses of complex interactions. Our data protection concept combined with the mobile application proves the feasibility of longitudinal assessment of anonymized participants. Our concept may serve as a blueprint for other studies handling sensitive data on HCW.

How do gravity alterations affect animal and human systems at a cellular/tissue level?

The present white paper concerns the indications and recommendations of the SciSpacE Science Community to make progress in filling the gaps of knowledge that prevent us from answering the question: "How Do Gravity Alterations Affect Animal and Human Systems at a Cellular/Tissue Level?" This is one of the five major scientific issues of the ESA roadmap "Biology in Space and Analogue Environments". Despite the many studies conducted so far on spaceflight adaptation mechanisms and related pathophysiological alterations observed in astronauts, we are not yet able to elaborate a synthetic integrated model of the many changes occurring at different system and functional levels. Consequently, it is difficult to develop credible models for predicting long-term consequences of human adaptation to the space environment, as well as to implement medical support plans for long-term missions and a strategy for preventing the possible health risks due to prolonged exposure to spaceflight beyond the low Earth orbit (LEO). The research activities suggested by the scientific community have the aim to overcome these problems by striving to connect biological and physiological aspects in a more holistic view of space adaptation effects.

Comprehensive assessment of physiological responses in women during the ESA dry immersion VIVALDI microgravity simulation

Astronauts in microgravity experience multi-system deconditioning, impacting their inflight efficiency and inducing dysfunctions upon return to Earth gravity. To fill the sex gap of knowledge in the health impact of spaceflights, we simulate microgravity with a 5-day dry immersion in 18 healthy women (ClinicalTrials.gov Identifier: NCT05043974). Here we show that dry immersion rapidly induces a sedentarily-like metabolism shift mimicking the beginning of a metabolic syndrome with a drop in glucose tolerance, an increase in the atherogenic index of plasma, and an impaired lipid profile. Bone remodeling markers suggest a decreased bone formation coupled with an increased bone resorption. Fluid shifts and muscular unloading participate to a marked cardiovascular and sensorimotor deconditioning with decreased orthostatic tolerance, aerobic capacity, and postural balance. Collected datasets provide a comprehensive multi-systemic assessment of dry immersion effects in women and pave the way for future sex-based evaluations of countermeasures.

Blood transcriptomics mirror regulatory mechanisms during hibernation-a comparative analysis of the Djungarian hamster with other mammalian species

Hibernation enables many species of the mammalian kingdom to overcome periods of harsh environmental conditions. During this physically inactive state metabolic rate and body temperature are drastically downregulated, thereby reducing energy requirements (torpor) also over shorter time periods. Since blood cells reflect the organism´s current condition, it was suggested that transcriptomic alterations in blood cells mirror the torpor-associated physiological state. Transcriptomics on blood cells of torpid and non-torpid Djungarian hamsters and QIAGEN Ingenuity Pathway Analysis (IPA) revealed key target molecules (TMIPA), which were subjected to a comparative literature analysis on transcriptomic alterations during torpor/hibernation in other mammals. Gene expression similarities were identified in 148 TMIPA during torpor nadir among various organs and phylogenetically different mammalian species. Based on TMIPA, IPA network analyses corresponded with described inhibitions of basic cellular mechanisms and immune system-associated processes in torpid mammals. Moreover, protection against damage to the heart, kidney, and liver was deduced from this gene expression pattern in blood cells. This study shows that blood cell transcriptomics can reflect the general physiological state during torpor nadir. Furthermore, the understanding of molecular processes for torpor initiation and organ preservation may have beneficial implications for humans in extremely challenging environments, such as in medical intensive care units and in space.

Differential effects of hypergravity on immune dysfunctions induced by simulated microgravity

Microgravity (μg) is among the major stressors in space causing immune cell dysregulations. These are frequently expressed as increased pro-inflammatory states of monocytes and reduced activation capacities in T cells. Hypergravity (as artificial gravity) has shown to have beneficial effects on the musculoskeletal and cardiovascular system both as a countermeasure option for μg-related deconditioning and as "gravitational therapy" on Earth. Since the impact of hypergravity on immune cells is sparsely explored, we investigated if an application of "mild" mechanical loading of 2.8 g is able to avoid or treat μg-mediated immune dysregulations. For this, T cell and monocyte activation states and cytokine pattern were first analyzed after whole blood antigen incubation in simulated μg (s-μg) by using the principle of fast clinorotation or in hypergravity. Subsequent hypergravity countermeasure approaches were run at three different sequences: one preconditioning setting, where 2.8 g was applied before s-μg exposure and two therapeutic approaches in which 2.8 g was set either intermediately or at the end of s-μg. In single g-grade exposure experiments, monocyte pro-inflammatory state was enhanced in s-μg and reduced in hypergravity, whereas T cells displayed reduced activation when antigen incubation was performed in s-μg. Hypergravity application in all three sequences did not alleviate the increased pro-inflammatory potential of monocytes. However, in T cells the preconditioning approach restored antigen-induced CD69 expression and IFNγ secretion to 1 g control values and beyond. This in vitro study demonstrates a proof of concept that mild hypergravity is a gravitational preconditioning option to avoid adaptive immune cell dysfunctions induced by (s-)μg and that it may act as a booster of immune cell functions.

Pathophysiology, risk, diagnosis, and management of venous thrombosis in space: where are we now?

The recent incidental discovery of an asymptomatic venous thrombosis (VT) in the internal jugular vein of an astronaut on the International Space Station prompted a necessary, immediate response from the space medicine community. The European Space Agency formed a topical team to review the pathophysiology, risk and clinical presentation of venous thrombosis and the evaluation of its prevention, diagnosis, mitigation, and management strategies in spaceflight. In this article, we discuss the findings of the ESA VT Topical Team over its 2-year term, report the key gaps as we see them in the above areas which are hindering understanding VT in space. We provide research recommendations in a stepwise manner that build upon existing resources, and highlight the initial steps required to enable further evaluation of this newly identified pertinent medical risk.

Are We Prepared for the Next Pandemic? Management, Systematic Evaluation and Lessons Learned from an In-Hospital COVID-19 Vaccination Centre for Healthcare Workers

BACKGROUND

the organisation of a COVID-19 vaccination campaign for healthcare workers (HCWs) within a university hospital presents a challenge of a particularly large scale and urgency. Here, we evaluate the in-hospital vaccination process and centre for HCWs at LMU University Hospital in Munich, Germany.

METHODS

We executed a mixed-method process evaluation of the vaccination centre at LMU University Hospital during the first COVID-19 vaccination campaign. In a programme monitoring, we continuously assessed the implementation of the centre's operational management including personnel resources. In evaluating the outreach to and satisfaction of the target group with the centre and process, we executed two anonymous surveys aimed at the HCWs vaccinated at the in-hospital centre (1) as well as centre staff members (2).

RESULTS

staff numbers and process time per person were reduced several times during the first vaccination campaign. Lessons concerning appointment scheduling were learned. HCWs vaccinated at the in-hospital centre were satisfied with the process. A longer waiting time between admission and inoculation, perceived dissatisfying accessibility as well as an increased frequency of observed adverse events were linked to a reduced satisfaction. Comparatively subpar willingness to adhere to non-pharmaceutical measures was observed. Centre staff reported high satisfaction and a workload relatively equal to that of their regular jobs. Our outcomes provide references for the implementation of an in-hospital vaccination centre in similar settings.

COVID-19 vaccination intent and associated factors in healthcare workers: cross-sectional study

Background

Considering the vaccine hesitancy recorded among healthcare workers (HCW) during the 2009/10 influenza pandemic, we aimed to examine the COVID-19 vaccination intent of HCW at one of the largest hospitals in Germany and to identify associated factors.

Methods

We conducted a cross-sectional anonymous survey at LMU University Hospital in Munich, Germany, between February 25 and March 20, 2021. Data was collected on COVID-19 vaccination intent as main outcome and on potential associated factors.

Results

In total, 2555 HCW completed the survey; 48,3% (n = 1325) of them had already received at least one COVID-19 vaccine dose. Of those not yet vaccinated 51,7% (n = 1320), 83,6% (n = 1104) reported intention to get vaccinated, while 10,2% (n = 134) were undecided and further 6,2% (n = 82) reported refusal. Disagreeing that everyone should receive the generally recommended vaccines was associated with refusal (RR = 529,500, p = 0,000) while being vaccinated against influenza in the 2020/21 season was linked with lower likelihood of refusal or indecisiveness (RR = 0,124, p = 0,000; RR = 0,182, p = 0,000). Low or partial conviction of the effectiveness and safety of COVID-19 vaccines were linked to refusal (effectiveness; RR = 485,471, p = 0,000; RR = 9,247, p = 0,000; safety: RR = 116,829, p = 0,000; RR = 5,423, p = 0,025). Feeling ill informed about COVID-19 vaccines was associated with refusal and indecisiveness (RR = 25,900, p = 0,000; RR = 21,104, p = 0,000).

Conclusions

At the beginning of the vaccination campaign in Germany, a small proportion of HCW at LMU University hospital was hesitant on receiving a COVID-19 vaccine. Factors associated with refusal or indecisiveness were a sceptical attitude towards vaccines in general as well as feeling ill informed about COVID-19 vaccines, especially regarding their effectiveness and safety. Having received an influenza vaccine was associated with COVID-19 vaccination intent.

Key messages

• The presented results provide insight into the reasons for hesitancy of HCW against COVID-19 vaccines, indicating a pattern-like behaviour in the acceptance of novel vaccines by HCW.

• The evidence from our analysis can help inform the communication aims and emphases of vaccination campaigns among HCW within similar organizational contexts or in future outbreak scenarios.

Influences on Glycocalyx Shedding during the Yukon Arctic Ultra: The Longest and the Coldest Ultramarathon

Introduction The endothelial glycocalyx maintains vascular structure and may be subject to shedding during inflammation, but also high-intensive exercise. There are no studies on shedding during ultra-endurance exercise. The "Yukon Arctic Ultra" (YAU) is one of the longest and coldest ultramarathons and its impact on glycocalyx shedding was investigated. Methods 13 adults (38.92 years ± 8.67, 6 female) of YAU editions 2015-2019 completed 657.03 km ± 71.65 at a moving velocity of 4.17 km/h ± 0.62. Mean daily temperatures ranged from ‒12.6°C to ‒30.5°C. Glycocalyx elements Heparan sulfate, Hyaluronan, and Syndecan CD-138 were quantified from serum at start, 277 km, 383 km, and 690 km. Cortisol, C-Reactive Protein, Creatine Kinase, and N-Terminal-Prohormone of Brain Natriuretic Peptide were also quantified. 7 YAU volunteers (36.14 years ± 11.04, 5 female) served as control. Results There were no time-changes among the control. Among finishers, there was a significant increase for Hyaluronan and a significant decrease for Syndecan CD-138. Values were greater among female finishers for Heparan sulfate at start, 383 km, and 690 km, and among male finishers for Hyaluronan at 277 km. Values for Syndecan CD-138 were greater among older finishers at all time points. There were weak significant correlations (R²<0.215) between Hyaluronan and distance, Creatine Kinase, and NT-Pro BNP, respectively. Conclusion Shedding of glycocalyx elements is shown among participants of the YAU. Greater shedding of Heparan sulfate among female, greater increases of Hyaluronan among male, and greater shedding of Syndecan CD-138 among older athletes indicate complex glycocalyx shedding during ultra-endurance exercise.

B-Cell Homeostasis Is Maintained During Two Months of Head-Down Tilt Bed Rest With or Without Antioxidant Supplementation

Alterations of the immune system could seriously impair the ability to combat infections during future long-duration space missions. However, little is known about the effects of spaceflight on the B-cell compartment. Given the limited access to astronaut samples, we addressed this question using blood samples collected from 20 healthy male volunteers subjected to long-duration bed rest, an Earth-based analog of spaceflight. Hematopoietic progenitors, white blood cells, total lymphocytes and B-cells, four B-cell subsets, immunoglobulin isotypes, six cytokines involved in inflammation, cortisone and cortisol were quantified at five time points. Tibia microarchitecture was also studied. Moreover, we investigated the efficiency of antioxidant supplementation with a cocktail including polyphenols, omega 3, vitamin E and selenium. Our results show that circulating hematopoietic progenitors, white blood cells, total lymphocytes and B-cells, and B-cell subsets were not affected by bed rest. Cytokine quantification suggested a lower systemic inflammatory status, supported by an increase in serum cortisone, during bed rest. These data confirm the in vivo hormonal dysregulation of immunity observed in astronauts and show that bed rest does not alter B-cell homeostasis. This lack of an impact of long-term bed rest on B-cell homeostasis can, at least partially, be explained by limited bone remodeling. None of the evaluated parameters were affected by the administration of the antioxidant supplement. The non-effectiveness of the supplement may be because the diet provided to the non-supplemented and supplemented volunteers already contained sufficient antioxidants. Given the limitations of this model, further studies will be required to determine whether B-cell homeostasis is affected, especially during future deep-space exploration missions that will be of unprecedented durations.

The Future of Personalized Medicine in Space: From Observations to Countermeasures

The aim of personalized medicine is to detach from a “one-size fits all approach” and improve patient health by individualization to achieve the best outcomes in disease prevention, diagnosis and treatment. Technological advances in sequencing, improved knowledge of omics, integration with bioinformatics and new in vitro testing formats, have enabled personalized medicine to become a reality. Individual variation in response to environmental factors can affect susceptibility to disease and response to treatments. Space travel exposes humans to environmental stressors that lead to physiological adaptations, from altered cell behavior to abnormal tissue responses, including immune system impairment. In the context of human space flight research, human health studies have shown a significant inter-individual variability in response to space analogue conditions. A substantial degree of variability has been noticed in response to medications (from both an efficacy and toxicity perspective) as well as in susceptibility to damage from radiation exposure and in physiological changes such as loss of bone mineral density and muscle mass in response to deconditioning. At present, personalized medicine for astronauts is limited. With the advent of longer duration missions beyond low Earth orbit, it is imperative that space agencies adopt a personalized strategy for each astronaut, starting from pre-emptive personalized pre-clinical approaches through to individualized countermeasures to minimize harmful physiological changes and find targeted treatment for disease. Advances in space medicine can also be translated to terrestrial applications, and vice versa. This review places the astronaut at the center of personalized medicine, will appraise existing evidence and future preclinical tools as well as clinical, ethical and legal considerations for future space travel.

Exploratory RNA-seq analysis in healthy subjects reveals vulnerability to viral infections during a 12- month period of isolation and confinement

Exposure to stressful environments weakens immunity evidenced by a detectable reactivation of dormant viruses. The mechanism behind this observation remains unclear. We performed next generation sequencing from RNA extracted from blood samples of 8 male subjects collected before, during and after a 12-month stay at the Antarctic station Concordia. RNA-seq data analysis was done using QIAGEN Ingenuity Pathway Analysis (IPA) software. Data revealed the inactivation of key immune functions such as chemotaxis and leukocyte recruitment which persisted after return. Next to the activation of the stress response eIF2 pathway, interferon signaling was predicted inactivated due to a downregulation of 14 downstream genes involved in antiviral immunity. Among them, the interferon stimulated genes (ISGs) IFITM2 and 3 as well as IFIT3 exhibited the strongest fold changes and IFIT3 remained downregulated even after return. Impairment of antiviral immunity in winter-over crew can be explained by the downregulation of a battery of ISGs.

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Whole blood transcriptome analysis during 12-months of isolation in the Antarctic.

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Data show an inactivation of key immune functions and pathways without recovery.

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The IFN pathway is most affected showing a downregulation of 14 downstream genes.

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The results suggest impairment of antiviral immunity and vulnerability to infection.

European space agency's hibernation (torpor) strategy for deep space missions: Linking biology to engineering

Long-duration space missions to Mars will impose extreme stresses of physical and psychological nature on the crew, as well as significant logistical and technical challenges for life support and transportation. Main challenges include optimising overall mass and maintaining crew physical and mental health. These key scopes have been taken up as the baseline for a study by the European Space Agency (ESA) using its Concurrent Design Facility (CDF). It focussed on the biology of hibernation in reducing metabolism and hence stress, and its links to the infrastructure and life support. We concluded that torpor of crew members can reduce the payload with respect to oxygen, food and water but will require monitoring and artificial intelligence (AI) assisted monitoring of the crew. These studies additionally offer new potential applications for patient care on Earth. Keywords: Space flight, concurrent design facility, metabolic reduction.

Progranulin signaling in sepsis, community-acquired bacterial pneumonia and COVID-19: a comparative, observational study

Background

Progranulin is a widely expressed pleiotropic growth factor with a central regulatory effect during the early immune response in sepsis. Progranulin signaling has not been systematically studied and compared between sepsis, community-acquired pneumonia (CAP), COVID-19 pneumonia and a sterile systemic inflammatory response (SIRS). We delineated molecular networks of progranulin signaling by next-generation sequencing (NGS), determined progranulin plasma concentrations and quantified the diagnostic performance of progranulin to differentiate between the above-mentioned disorders using the established biomarkers procalcitonin (PCT), interleukin-6 (IL-6) and C-reactive protein (CRP) for comparison.

Methods

The diagnostic performance of progranulin was operationalized by calculating AUC and ROC statistics for progranulin and established biomarkers in 241 patients with sepsis, 182 patients with SIRS, 53 patients with CAP, 22 patients with COVID-19 pneumonia and 53 healthy volunteers. miRNAs and mRNAs in blood cells from sepsis patients (n = 7) were characterized by NGS and validated by RT-qPCR in an independent cohort (n = 39) to identify canonical gene networks associated with upregulated progranulin at sepsis onset.

Results

Plasma concentrations of progranulin (ELISA) in patients with sepsis were 57.5 (42.8–84.9, Q25–Q75) ng/ml and significantly higher than in CAP (38.0, 33.5–41.0 ng/ml, p < 0.001), SIRS (29.0, 25.0–35.0 ng/ml, p < 0.001) and the healthy state (28.7, 25.5–31.7 ng/ml, p < 0.001). Patients with COVID-19 had significantly higher progranulin concentrations than patients with CAP (67.6, 56.6–96.0 vs. 38.0, 33.5–41.0 ng/ml, p < 0.001). The diagnostic performance of progranulin for the differentiation between sepsis vs. SIRS (n = 423) was comparable to that of procalcitonin. AUC was 0.90 (95% CI = 0.87–0.93) for progranulin and 0.92 (CI = 0.88–0.96, p = 0.323) for procalcitonin. Progranulin showed high discriminative power to differentiate bacterial CAP from COVID-19 (sensitivity 0.91, specificity 0.94, AUC 0.91 (CI = 0.8–1.0) and performed significantly better than PCT, IL-6 and CRP. NGS and partial RT-qPCR confirmation revealed a transcriptomic network of immune cells with upregulated progranulin and sortilin transcripts as well as toll-like-receptor 4 and tumor-protein 53, regulated by miR-16 and others.

Conclusions

Progranulin signaling is elevated during the early antimicrobial response in sepsis and differs significantly between sepsis, CAP, COVID-19 and SIRS. This suggests that progranulin may serve as a novel indicator for the differentiation between these disorders.

Trial registration: Clinicaltrials.gov registration number NCT03280576 Registered November 19, 2015.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40635-021-00406-7.

COVID-19 Impairs Immune Response to Candida albicans

Infection with SARS-CoV-2 can lead to Coronavirus disease-2019 (COVID-19) and result in severe acute respiratory distress syndrome (ARDS). Recent reports indicate an increased rate of fungal coinfections during COVID-19. With incomplete understanding of the pathogenesis and without any causative therapy available, secondary infections may be detrimental to the prognosis. We monitored 11 COVID-19 patients with ARDS for their immune phenotype, plasma cytokines, and clinical parameters on the day of ICU admission and on day 4 and day 7 of their ICU stay. Whole blood stimulation assays with lipopolysaccharide (LPS), heat-killed Listeria monocytogenes (HKLM), Aspergillus fumigatus, and Candida albicans were used to mimic secondary infections, and changes in immune phenotype and cytokine release were assessed. COVID-19 patients displayed an immune phenotype characterized by increased HLA-DR⁺CD38⁺ and PD-1⁺ CD4⁺ and CD8⁺ T cells, and elevated CD8⁺CD244⁺ lymphocytes, compared to healthy controls. Monocyte activation markers and cytokines IL-6, IL-8, TNF, IL-10, and sIL2Rα were elevated, corresponding to monocyte activation syndrome, while IL-1β levels were low. LPS, HKLM and Aspergillus fumigatus antigen stimulation provoked an immune response that did not differ between COVID-19 patients and healthy controls, while COVID-19 patients showed an attenuated monocyte CD80 upregulation and abrogated release of IL-6, TNF, IL-1α, and IL-1β toward Candida albicans. This study adds further detail to the characterization of the immune response in critically ill COVID-19 patients and hints at an increased susceptibility for Candida albicans infection.

COVID-19-The largest isolation study in history: the value of shared learnings from spaceflight analogs

The world is currently experiencing the largest isolation experiment in history. In an attempt to slow down the spread of the COVID-19 pandemic numerous countries across the world have been shutting down economies, education, and public life. Governments have mandated strict regulations of quarantine and social distancing in an unprecedented manner. The effects of these measures on brain, behavior, neuro-humoral and immunological responses in humans are largely unknown. Life science research for space exploration has a long history in using high-fidelity spaceflight analogs to better understand the effect of prolonged isolation and confinement on genes, molecules, cells, neural circuits, and physiological systems to behavior. We here propose to leverage the extensive experience and data from these studies and build a bridge between spaceflight research and clinical settings to foster transdisciplinary approaches to characterize the neurobehavioral effects on the immune system and vice versa. These approaches are expected to develop innovative and efficient health screening tools, diagnostic systems, and treatments to mitigate health risks associated with isolation and confinement on Earth and during future exploratory spaceflight missions.

Plasticity of the human IgM repertoire in response to long-term spaceflight

Immune dysregulation is among the main adverse outcomes of spaceflight. Despite the crucial role of the antibody repertoire in host protection, the effects of spaceflight on the human antibody repertoire are unknown. Consequently, using high-throughput sequencing, we examined the IgM repertoire of five cosmonauts 25 days before launch, after 64 ± 11 and 129 ± 20 days spent on the International Space Station (ISS), and at 1, 7, and 30 days after landing. This is the first study of this kind in humans. Our data revealed that the IgM repertoire of the cosmonauts was different from that of control subjects (n = 4) prior to launch and that two out the five analyzed cosmonauts presented significant changes in their IgM repertoire during the mission. These modifications persisted up to 30 days after landing, likely affected the specificities of IgM binding sites, correlated with changes in the V(D)J recombination process responsible for creating antibody genes, and coincided with a higher stress response. These data confirm that the immune system of approximately half of the astronauts who spent 6 months on the ISS is sensitive to spaceflight conditions, and reveal individual responses indicating that personalized approaches should be implemented during future deep-space exploration missions that will be of unprecedented durations.

Changes of brain DTI in healthy human subjects after 520 days isolation and confinement on a simulated mission to Mars

INTRODUCTION

Long-term confinement is known to be a stressful experience with multiple psycho-physiological effects. In the MARS500 project, a real-time simulation of a space-flight to Mars conducted in a hermetically isolated habitat, effects of long-term confinement could be investigated in a unique manner. The aim of this study was to evaluate effects of long-term-confinement on brain cytoarchitecture.

MATERIAL & METHODS

The participants of the MARS500 project underwent 3T-MR imaging including a dedicated DTI-sequence before the isolation, right after ending of confinement and 6 months after the experiment. Voxelwise statistical analysis of the DTI data was carried out using tract-based-spatial statistics, comparing an age-matched control group.

RESULTS

At all three sessions, significant lower fractional anisotropy (FA) than in controls was found in the anterior parts of the callosal body of the participants. Furthermore, after ending of confinement a wide-spread FA reduction could be seen in the right hemisphere culminating in the temporo-parietal-junction-zone. All these areas with decreased FA predominantly showed an elevated radial diffusivity and mean diffusivity while axial diffusivity was less correlated.

DISCUSSION

Long-term confinement does have measurable effects on the microstructure of the brain white matter. We assume effects of sensory deprivation to account for the regional FA reductions seen in the right TPJ. The differences in the Corpus callosum were interpreted as due to preliminary conditions, e.g. personality traits or training effects. FA and radial diffusivity were the predominant DTI parameters with significant changes, suggesting underlying processes of myelin plasticity.

Effect of high altitude and exercise on microvascular parameters in acclimatized subjects

The role of microvascular fluid shifts in the adaptation to hypobaric hypoxia and its contribution to the pathophysiology of AMS (acute mountain sickness) is unresolved. In a systematic prospective study, we investigated the effects of hypobaric hypoxia and physical exercise alone, and in combination, on microvascular fluid exchange and related factors. We used computer-assisted VCP (venous congestion plethysmography) on the calves of ten altitude-acclimatized volunteers. We investigated the effects of: (i) actively climbing to an altitude of 3196 m, (ii) airlifting these subjects to the same altitude, and (iii) exercise at low altitude. CFC (capillary filtration capacity), Pvi (isovolumetric venous pressure) and Qa (calf blood flow) were assessed before and after each procedure and then repeated after an overnight rest. Measurements of CFC showed no evidence of increased microvascular permeability after any of the procedures. Pvi was significantly decreased (P<0.001) from 20.3±4.4 to 8.9±4.3 mmHg after active ascent, and was still significantly lower (P=0.009) after overnight rest at high altitude (13.6±5.9 mmHg). No such changes were observed after the passive ascent (16.7±4.0 mmHg at baseline; 17.3±4.5 mmHg after passive ascent; and 19.9±5.3 mmHg after overnight rest) or after exercise at low altitude. After the active ascent, Qa was significantly increased. We also found a significant correlation between Qa, Pvi and the number of circulating white blood cells. In conclusion, we found evidence to support the hypothesis that increased microvascular permeability associated with AMS does not occur in acclimatized subjects. We also observed that the microvascular equilibrium pressure (Pvi) fell in inverse relation to the increase in Qa, especially in hypoxic exercise. We hypothesize that this inverse relationship reflects the haemodynamic changes at the microvascular interface, possibly attributable to the flow-induced increases in endothelial surface shear forces.

Alpha-gluthathione S-transferase as an early marker of hepatic ischemia/reperfusion injury after liver resection

Organ dysfunction following liver resection is one of the major postoperative complications of liver surgery. The Pringle maneuver is often applied during liver resection to minimize bleeding, which in turn complicates the postoperative course owing to liver ischemia and reperfusion. Routinely, hepatocellular damage is diagnosed by, for example, abnormal aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels and the prothrombin time (PT). The cytosolic liver enzyme alpha-glutathione S-transferase (alpha-GST) has recently been shown to have good sensitivity for detecting hepatic injury after acetaminophen poisoning or liver transplantation, but its role in non-transplantation liver surgery has not been assessed. In this prospective randomized clinical study, the diagnostic role of plasma alpha-GST following warm ischemia and reperfusion is reported. A total of 75 patients who underwent liver resection were randomly assigned to three groups: (1) without Pringle (NPR); (2) with Pringle (PR); (3) with ischemic preconditioning by 10 minutes of ischemia and reperfusion each prior to the Pringle manuever (IPC). The major findings are as follows: (1) ALT, AST, and alpha-GST increased upon liver manipulation as early as prior to resection, with a rapid return of alpha-GST values to preoperative levels, whereas ALT and AST further increased on the first postoperative day. (2) In the PR group, alpha-GST, but not ALT and AST, was significantly elevated compared with that in the NPR group at 15 and 30 minutes and 2 hours after resection/reperfusion. In addition, only levels of alpha-GST significantly correlated with the Pringle duration. (3) The ischemia/reperfusion-induced early rise in alpha-GST was completely prevented by ischemic preconditioning. Moreover, only alpha-GST concentrations (> 490 microg L(-1)) determined early after resection (2 hours) predicted postoperative liver dysfunction (24 hours PT < 60%) with a positive predictive value of 74% and a negative predictive value of 76%. Thus alpha-GST seems to be a sensitive, predictive marker of ischemia/reperfusion-induced hepatocellular injury and postoperative liver dysfunction.