Quantifizierung des dreidimensionalen glomerulären Kapillarsystems von Schweinen mittels der Mikro– und Nano– Computertomographie

Hintergrund: Die vorliegende Arbeit präsentiert die dreidimensionale Darstellung und Quantifizierung des renalen Gefäßsystems von Schlachthausschweinen und domestizierten Minipigs mittels der Mikro- und Nano – CT. Material und Methoden: Um den renalen porcinen Gefäßbaum dreidimensional darzustellen und zu quantifizieren, werden zwei Studienkollektive aus fünf Schlachthausschweinen (Studienpopulation: 1, Alter: 6 Monate; Gewicht: 120 kg) und sieben domestizierten Minipigs (Studienpopulation: 2, Alter: 25 Wochen, Gewicht: 45 – 55 kg) gebildet. Die Nieren werden entweder mit einer Mischung aus BaSO4 und Gelantine (SP 1) oder mit Microfil® (SP 2) perfundiert. Anschließend werden aus den Nieren Stanzen gewonnen, diese fixiert und mittels der Mikro- und Nano – CT gescannt. Mit der Mikro – CT und Nano – CT werden der glomeruläre Durchmesser (mm), Fläche (mm2), Volumen (mm3) und die Gesamtanzahl der Glomeruli pro Fläche (n/mm2) bestimmt. Mit der Nano – CT wird zusätzlich zu den genannten Parametern das intraglomeruläre Kapillarvolumen (mm3) quantifiziert. Die gewonnenen Daten werden mit der Histologie verglichen. Ergebnisse: In der Analyse der Daten des Studienkollektivs 1 stellt sich eine signifikante Zunahme der Messwerte ausgehend von der histomorphometrischen Untersuchung über die NCT zu der &#956;CT – Untersuchung (0,231 &#61617;&#61472;0,03 mm, 0,033 &#61617;&#61472;0,01 mm²; 0,252 &#61617;&#61472;0,028 mm, 0,041 &#61617;&#61472;0,01 mm², 0,0057 &#61617;&#61472;0,0025 mm3; 0,269 &#61617;&#61472;0,037 mm, 0,047 &#61617;&#61472;0,01mm², 0,0067 &#61617;&#61472;0,0025 mm3, p < 0,001). Die quantitative Analyse des glomerulären und kapillären Volumens (SK 1) und Fläche (SK 2) zeigt eine signifikante Korrelation der Parameter zueinander (r2 = 0,97, r2 = 0,19 ). Die Nano – CT – Untersuchungen der Studien-population 2 ergeben ebenfalls signifikant höhere Resultate als deren histologischen Korrelate (0,139 &#61617;&#61472;0,019 mm, 0,016 &#61617;&#61472;0,004 mm2, 0,12 &#61617;&#61472;0,02 mm, 0,011 &#61617;&#61472;0,003 mm2, p < 0,001). Schlussfolgerung Die Ergebnisse weisen auf einen potentiellen Nutzen der 3D – Visualisierung und Quantifikation mittels der Mikro- und Nano - CT zur Evaluierung glomerulärer und vaskulärer Anteile der Niere und könnten somit für die Erforschung renaler und hypertensiver Erkrankungen von Nutzen sein.Background: This study is designed to evaluate the feasibility for analysis of the kidney glomeruli capillary unit in adult and domestic pics using micro- and nano – CT imaging. Methods: Kidneys were harvested from five healthy hybrid pics (study population 1, 6 months of age; weight 120 kg) at a local slaughterhouse and seven kidneys from healthy domestic minipigs (study population 2, 25 weeks of age, weight 45 – 55 kg). They were infused either with a mixture of BaSO4 and gelatine (SP 1) or Microfil® (SP 2). Kidney samples were punched out, harvested and scanned with micro – CT and nano – CT. Diameter (mm) and cross-sectional area (mm2) of glomeruli were measured using micro – CT, nano – CT and histology. The capillary vessel volume (mm³) within single glomeruli was quantitated using nano – CT. Results were complemented by colocalized histology. Results: Within the study population 1 glomeruli diameter, crosssectional area and glomerulary volume increased significantly as measured by histology, nano – CT and micro – CT (0.231 &#61617;&#61472;0.03 mm, 0.033 &#61617;&#61472;0.01 mm²; 0.252 &#61617;&#61472;0.028 mm, 0.041 &#61617;&#61472;0.01 mm², 0.0057 &#61617;&#61472;0.0025 mm3; 0.269 &#61617;&#61472;0.037 mm, 0.047 &#61617;&#61472;0.01mm², 0.0067 &#61617;&#61472;0.0025 mm3, p < 0.001; respectively). Quantitative nano – CT analysis demonstrated a strong linear relationship of the volume of glomeruli and the capillary volume (r² = 0.97). In study population 2 the analysis shows comparable results relating to study population1. Nano – CT measurements demonstrate significant higher values as in histological analysis (0.139 &#61617;&#61472;0.019 mm, 0.016 &#61617;&#61472;0.004 mm2, 0.12 &#61617;&#61472;0.02 mm, 0.011 &#61617;&#61472;0.003 mm2, p < 0.001). The capillary surface area relates strongly to the glomerulary surface area (r2 = 0.19). Conclusion: These results demonstrate potential use of quantitative 3D micro- and nano – CT imaging to obtain information about glomeruli dimensions´ and vascularisation, which could be useful in animal models of kidney alterations

Nucleated red blood cells are a late biomarker in predicting intensive care unit mortality in patients with COVID-19 acute respiratory distress syndrome: an observational cohort study

BackgroundNucleated red blood cells (nRBC) are precursor cells of the erythropoiesis that are absent from the peripheral blood under physiological conditions. Their presence is associated with adverse outcomes in critically ill patients. This study aimed to evaluate the predictive value of nRBC on mortality in intensive care unit (ICU) patients with COVID-19 acute respiratory distress syndrome (ARDS).Material and methodsThis retrospective, observational cohort study analyzed data on 206 ICU patients diagnosed with COVID-19 ARDS between March 2020 and March 2022. The primary endpoint was ICU mortality, and secondary endpoints included ICU and hospital stay lengths, ventilation hours, and the time courses of disease severity scores and clinical and laboratory parameters.ResultsAmong the included patients, 68.9% tested positive for nRBC at least once during their ICU stay. A maximum nRBC of 105 µl-1 had the highest accuracy in predicting ICU mortality (area under the curve of the receiver operating characteristic [AUCROC] 0.780, p &lt; 0.001, sensitivity 69.0%, specificity 75.5%). Mortality was significantly higher among patients with nRBC &gt;105 µl-1 than ≤105 µl-1 (86.5% vs. 51.3%, p = 0.008). Compared to patients negative for nRBC in their peripheral blood, those positive for nRBC required longer mechanical ventilation (127 [44 - 289] h vs. 517 [255 - 950] h, p &lt; 0.001), ICU stays (12 [8 – 19] vs. 27 [13 – 51] d, p &lt; 0.001), and hospital stays (19 [12 - 29] d vs. 31 [16 - 58] d, p &lt; 0.001). Peak Sepsis-related Organ Failure Assessment (SOFA), Simplified Acute Physiology Score, PaO2/FiO2, interleukin-6, and procalcitonin values were reached before the peak nRBC level. However, the predictive performance of the SOFA (AUCROC 0.842, p &lt; 0.001) was considerably improved when a maximum SOFA score &gt;8 and nRBC &gt;105 µl-1 were combined.DiscussionnRBC predict ICU mortality and indicate disease severity among patients with COVID-19 ARDS, and they should be considered a clinical alarm signal for a worse outcome. nRBC are a late predictor of ICU mortality compared to other established clinical scoring systems and laboratory parameters but improve the prediction accuracy when combined with the SOFA score

T Cells Enhance Stem-Like Properties and Conditional Malignancy in Gliomas

Small populations of highly tumorigenic stem-like cells (cancer stem cells; CSCs) can exist within, and uniquely regenerate cancers including malignant brain tumors (gliomas). Many aspects of glioma CSCs (GSCs), however, have been characterized in non-physiological settings.We found gene expression similarity superiorly defined glioma "stemness", and revealed that GSC similarity increased with lower tumor grade. Using this method, we examined stemness in human grade IV gliomas (GBM) before and after dendritic cell (DC) vaccine therapy. This was followed by gene expression, phenotypic and functional analysis of murine GL26 tumors recovered from nude, wild-type, or DC-vaccinated host brains.GSC similarity was specifically increased in post-vaccine GBMs, and correlated best to vaccine-altered gene expression and endogenous anti-tumor T cell activity. GL26 analysis confirmed immune alterations, specific acquisition of stem cell markers, specifically enhanced sensitivity to anti-stem drug (cyclopamine), and enhanced tumorigenicity in wild-type hosts, in tumors in proportion to anti-tumor T cell activity. Nevertheless, vaccine-exposed GL26 cells were no more tumorigenic than parental GL26 in T cell-deficient hosts, though they otherwise appeared similar to GSCs enriched by chemotherapy. Finally, vaccine-exposed GBM and GL26 exhibited relatively homogeneous expression of genes expressed in progenitor cells and/or differentiation.T cell activity represents an inducible physiological process capable of proportionally enriching GSCs in human and mouse gliomas. Stem-like gliomas enriched by strong T cell activity, however, may differ from other GSCs in that their stem-like properties may be disassociated from increased tumor malignancy and heterogeneity under specific host immune conditions

Pediatric trauma and emergency surgery: an international cross-sectional survey among WSES members

Background: In contrast to adults, the situation for pediatric trauma care from an international point of view and the global management of severely injured children remain rather unclear. The current study investigates structural management of pediatric trauma in centers of different trauma levels as well as experiences with pediatric trauma management around the world. Methods: A web-survey had been distributed to the global mailing list of the World Society of Emergency Surgery from 10/2021-03/2022, investigating characteristics of respondents and affiliated hospitals, case-load of pediatric trauma patients, capacities and infrastructure for critical care in children, trauma team composition, clinical work-up and individual experiences with pediatric trauma management in response to patients´ age. The collaboration group was subdivided regarding sizes of affiliated hospitals to allow comparisons concerning hospital volumes. Comparable results were conducted to statistical analysis. Results: A total of 133 participants from 34 countries, i.e. 5 continents responded to the survey. They were most commonly affiliated with larger hospitals (&gt; 500 beds in 72.9%) and with level I or II trauma centers (82.0%), respectively. 74.4% of hospitals offer unrestricted pediatric medical care, but only 63.2% and 42.9% of the participants had sufficient experiences with trauma care in children ≤ 10 and ≤ 5&nbsp;years of age (p = 0.0014). This situation is aggravated in participants from smaller hospitals (p &lt; 0.01). With regard to hospital size (≤ 500 versus &gt; 500 in-hospital beds), larger hospitals were more likely affiliated with advanced trauma centers, more elaborated pediatric intensive care infrastructure (p &lt; 0.0001), treated children at all ages more frequently (p = 0.0938) and have higher case-loads of severely injured children &lt; 12&nbsp;years of age (p = 0.0009). Therefore, the majority of larger hospitals reserve either pediatric surgery departments or board-certified pediatric surgeons (p &lt; 0.0001) and in-hospital trauma management is conducted more multi-disciplinarily. However, the majority of respondents does not feel prepared for treatment of severe pediatric trauma and call for special educational and practical training courses (overall: 80.2% and 64.3%, respectively). Conclusions: Multi-professional management of pediatric trauma and individual experiences with severely injured children depend on volumes, level of trauma centers and infrastructure of the hospital. However, respondents from hospitals at all levels of trauma care complain about an alarming lack of knowledge on pediatric trauma management

Correction to: Two years later: Is the SARS-CoV-2 pandemic still having an impact on emergency surgery? An international cross-sectional survey among WSES members

Background: The SARS-CoV-2 pandemic is still ongoing and a major challenge for health care services worldwide. In the first WSES COVID-19 emergency surgery survey, a strong negative impact on emergency surgery (ES) had been described already early in the pandemic situation. However, the knowledge is limited about current effects of the pandemic on patient flow through emergency rooms, daily routine and decision making in ES as well as their changes over time during the last two pandemic years. This second WSES COVID-19 emergency surgery survey investigates the impact of the SARS-CoV-2 pandemic on ES during the course of the pandemic. Methods: A web survey had been distributed to medical specialists in ES during a four-week period from January 2022, investigating the impact of the pandemic on patients and septic diseases both requiring ES, structural problems due to the pandemic and time-to-intervention in ES routine. Results: 367 collaborators from 59 countries responded to the survey. The majority indicated that the pandemic still significantly impacts on treatment and outcome of surgical emergency patients (83.1% and 78.5%, respectively). As reasons, the collaborators reported decreased case load in ES (44.7%), but patients presenting with more prolonged and severe diseases, especially concerning perforated appendicitis (62.1%) and diverticulitis (57.5%). Otherwise, approximately 50% of the participants still observe a delay in time-to-intervention in ES compared with the situation before the pandemic. Relevant causes leading to enlarged time-to-intervention in ES during the pandemic are persistent problems with in-hospital logistics, lacks in medical staff as well as operating room and intensive care capacities during the pandemic. This leads not only to the need for triage or transferring of ES patients to other hospitals, reported by 64.0% and 48.8% of the collaborators, respectively, but also to paradigm shifts in treatment modalities to non-operative approaches reported by 67.3% of the participants, especially in uncomplicated appendicitis, cholecystitis and multiple-recurrent diverticulitis. Conclusions: The SARS-CoV-2 pandemic still significantly impacts on care and outcome of patients in ES. Well-known problems with in-hospital logistics are not sufficiently resolved by now; however, medical staff shortages and reduced capacities have been dramatically aggravated over last two pandemic years

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

The Role of the Kinin System and the Effect of Des-Arginine⁹-Bradykinin on Coagulation and Platelet Function in Critically Ill COVID-19 Patients: A Secondary Analysis of a Prospective Observational Study

The effect of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on the coagulation system is not fully understood. SARS-CoV-2 penetrates cells through angiotensin-converting enzyme 2 (ACE2) receptors, leading to its downregulation. Des-arginine9-bradykinin (DA9B) is degraded by ACE2 and causes vasodilation and increased vascular permeability. Furthermore, DA9B is associated with impaired platelet function. Therefore, the aim of this study was to evaluate the effects of DA9B on platelet function and coagulopathy in critically ill coronavirus disease 2019 (COVID-19) patients. In total, 29 polymerase-positive SARS-CoV-2 patients admitted to the intensive care unit of the University Hospital of Giessen and 29 healthy controls were included. Blood samples were taken, and platelet impedance aggregometry and rotational thromboelastometry were performed. Enzyme-linked immunosorbent assays measured the concentrations of DA9B, bradykinin, and angiotensin 2. Significantly increased concentrations of DA9B and angiotensin 2 were found in the COVID-19 patients. A negative effect of DA9B on platelet function and intrinsic coagulation was also found. A sub-analysis of moderate and severe acute respiratory distress syndrome patients revealed a negative association between DA9B and platelet counts and fibrinogen levels. DA9B provokes inhibitory effects on the intrinsic coagulation system in COVID-19 patients. This negative feedback seems reasonable as bradykinin, which is transformed to DA9B, is released after contact activation. Nevertheless, further studies are needed to confirm our findings

Peak Plasma Levels of mtDNA Serve as a Predictive Biomarker for COVID-19 in-Hospital Mortality

Several predictive biomarkers for coronavirus disease (COVID-19)-associated mortality in critically ill patients have been described. Although mitochondrial DNA (mtDNA) is elevated in patients with COVID-19, the association with coagulation function and its predictive power for mortality is unclear. Accordingly, this study investigates the predictive power of mtDNA for in-hospital mortality in critically ill patients with COVID-19, and whether combining it with thromboelastographic parameters can increase its predictive performance. This prospective explorative study included 29 patients with COVID-19 and 29 healthy matched controls. mtDNA encoding for NADH dehydrogenase 1 (ND1) was quantified using a quantitative polymerase chain reaction analysis, while coagulation function was evaluated using thromboelastometry and impedance aggregometry. Receiver operating characteristic (ROC) curves were used for the prediction of in-hospital mortality. Within the first 24 h, the plasma levels of mtDNA peaked significantly (controls: 65 (28–119) copies/µL; patients: 281 (110–805) at t0, 403 (168–1937) at t24, and 467 (188–952) copies/µL at t72; controls vs. patients: p = 0.02 at t0, p = 0.03 at t24, and p = 0.44 at t72). The mtDNA levels at t24 showed an excellent predictive performance for in-hospital mortality (area under the ROC curve: 0.90 (0.75–0.90)), which could not be improved by the combination with thromboelastometric or aggregometric parameters. Critically ill patients with COVID-19 present an early increase in the plasma levels of ND1 mtDNA, lasting over 24 h. They also show impairments in platelet function and fibrinolysis, as well as hypercoagulability, but these do not correlate with the plasma levels of fibrinogen. The peak plasma levels of mtDNA can be used as a predictive biomarker for in-hospital mortality; however, the combination with coagulation parameters does not improve the predictive validity