HSPA8 chaperone complex drives chaperone-mediated autophagy regulation in acute promyelocytic leukemia cell differentiation.

INTRODUCTION: Acute myeloid leukemia (AML) is a cancer of the hematopoietic system characterized by hyperproliferation of undifferentiated cells of the myeloid lineage. While most of AML therapies are focused towards tumor debulking, all-trans retinoic acid (ATRA) induces neutrophil differentiation in the AML subtype acute promyelocytic leukemia (APL). Macroautophagy has been extensively investigated in the context of various cancers and is often dysregulated in AML where it can have context-dependent pro- or anti-leukemogenic effects. On the contrary, the implications of chaperone-mediated autophagy (CMA) on the pathophysiology of diseases are still being explored and its role in AML has remains elusive. METHODS: We took advantages of human AML primary samples and databases to analyze CMA gene expression and activity. Furthermore, we used ATRA-sensitive (NB4) and -resistant (NB4-R1) cells to further dissect a potential function for CMA in ATRA-mediated neutrophil differentiation. NB4-R1 cells are unique in that they do respond to retinoic acid transcriptionally, but do not mature in response to retinoid signaling alone unless maturation is triggered by adding cAMP. RESULTS: Here, we report that CMA related mRNA transcripts are significantly higher expressed in immature hematopoietic cells as compared to neutrophils, contrasting the macroautophagy gene expression patterns. Accordingly, lysosomal degradation of an mCherry-KFERQ CMA reporter decreases during ATRA-induced differentiation of APL cells. On the other hand, using NB4-R1 cells we found that macroautophagy flux primed ATRA resistant NB4-R1 cells to differentiate upon ATRA treatment, but reduced association of lysosome-associated membrane protein type 2A (LAMP-2A) and heat shock protein family A (Hsp70) member 8 (HSPA8), which are necessary for complete neutrophil maturation. Accordingly, depletion of HSPA8 attenuated CMA activity and facilitated APL cell differentiation. In contrast, maintaining high CMA activity by ectopic expression of LAMP-2A impeded APL differentiation. CONCLUSION: Overall, our findings suggest that APL neutrophil differentiation requires CMA inactivation and that this pathway predominantly depends on HSPA8 and is possibly assisted by other co-chaperones.

Operating under the influence: the effect of alcohol on operative performance using a virtual robotic training platform-an experimental comparative cohort study.

An elevated percentage of medical personnel reports using alcohol to relieve stress. Levels of alcohol addiction are almost double that of the general population. Robotic surgery is becoming more widespread. The purpose of this study is to evaluate the effects of alcohol ingestion on performance of a standardized curriculum using a robotic training platform. Surgeons and surgical trainees were recruited. Candidates performed 4 standardized exercises (Vitruvian Operation (VO), Stacking Challenge (SC), Ring Tower (RT), Suture Sponge (SS)) at 0.0 blood alcohol concentration (BAC), followed by testing in the elimination phase at a target BAC of 0.8‰. Learning effects were minimised through prior training. A total of 20 participants were recruited. Scores for RT and SS exercises were significantly worse under the influence of alcohol [instruments out of view (SS (z = 2.012; p = 0.044), RT (z score 1.940, p = 0.049)), drops (SS (z = 3.250; p = 0.001)), instrument collisions (SS (z = 2.460; p = 0.014)), missed targets (SS (z = 2.907; p = 0.004)]. None of the scores improved with alcohol consumption, and there were measurable deleterious effects on the compound indicators risk affinity and tissue handling. Despite the potential mitigating features of robotic surgery including tremor filtration, motion scaling, and improved three-dimensional visualization, alcohol consumption was associated with a significant increase in risk affinity and rough tissue handling, along with a deterioration of performance in select virtual robotic tasks. In the interest of patient safety, alcohol should not be consumed prior to performing robotic surgery and sufficiently long intervals between alcohol ingestion and surgical performance are mandatory.

Can perioperative pCO2 gaps predict complications in patients undergoing major elective abdominal surgery randomized to goal-directed therapy or standard care? A secondary analysis.

The difference between venous and arterial carbon dioxide pressure (pCO2 gap), has been used as a diagnostic and prognostic tool. We aimed to assess whether perioperative pCO2 gaps can predict postoperative complications. This was a secondary analysis of a multicenter RCT comparing goal-directed therapy (GDT) to standard care in which 464 patients undergoing high-risk elective abdominal surgery were included. Arterial and central venous blood samples were simultaneously obtained at four time points: after induction, at the end of surgery, at PACU/ICU admission, and PACU/ICU discharge. Complications within the first 30 days after surgery were recorded. Similar pCO2 gaps were found in patients with and without complications, except for the pCO2 gap at the end of surgery, which was higher in patients with complications (6.0 mmHg [5.0-8.0] vs. 6.0 mmHg [4.1-7.5], p = 0.005). The area under receiver operating characteristics curves for predicting complications from pCO2 gaps at all time points were between 0.5 and 0.6. A weak correlation between ScvO2 and pCO2 gaps was found for all timepoints (ρ was between - 0.40 and - 0.29 for all timepoints, p < 0.001). The pCO2 gap did not differ between GDT and standard care at any of the selected time points. In our study, pCO2 gap was a poor predictor of major postoperative complications at all selected time points. Our research does not support the use of pCO2 gap as a prognostic tool after high-risk abdominal surgery. pCO2 gaps were comparable between GDT and standard care. Clinical trial registration Netherlands Trial Registry NTR3380.

Non-canonical BIM-regulated energy metabolism determines drug-induced liver necrosis.

Paracetamol (acetaminophen, APAP) overdose severely damages mitochondria and triggers several apoptotic processes in hepatocytes, but the final outcome is fulminant necrotic cell death, resulting in acute liver failure and mortality. Here, we studied this switch of cell death modes and demonstrate a non-canonical role of the apoptosis-regulating BCL-2 homolog BIM/Bcl2l11 in promoting necrosis by regulating cellular bioenergetics. BIM deficiency enhanced total ATP production and shifted the bioenergetic profile towards glycolysis, resulting in persistent protection from APAP-induced liver injury. Modulation of glucose levels and deletion of Mitofusins confirmed that severe APAP toxicity occurs only in cells dependent on oxidative phosphorylation. Glycolytic hepatocytes maintained elevated ATP levels and reduced ROS, which enabled lysosomal recycling of damaged mitochondria by mitophagy. The present study highlights how metabolism and bioenergetics affect drug-induced liver toxicity, and identifies BIM as important regulator of glycolysis, mitochondrial respiration, and oxidative stress signaling.

Glucose measurements with accu check inform II versus hexokinase plasma method during surgery under general anesthesia, an observational cohort study.

PURPOSE: Limited research exists on translation of in-vitro glucose measurement interfering compounds to the in-vivo situation. We investigated whether Point-of-Care glucose measurements by Accu Chek Inform II (ACI II) were accurate to monitor glucose concentrations during surgery with general anesthesia by comparing with the reference laboratory hexokinase plasma glucose test. METHOD: Patients undergoing surgery with general anesthesia were included. Anesthesia was maintained with either Sevoflurane or Total intravenous anesthesia (TIVA). Prior to and after induction, blood glucose was measured with ACI II and the hexokinase test. Bland-Altman analysis was performed to assess method agreement. Subgroup analyses on glucose measurement differences per type of maintenance anesthesia were performed. RESULTS: Thirty-nine patients were included, and 78 measurements were performed. All paired measurements had clinically acceptable agreement with a percentage error of 10.0% (95% CI 8.0 to 11.9). The mean difference (95% limits of agreement) between ACI II and hexokinase for all measurements was 0.0 mmol/L (-0.7 to 0.7 mmol/L). Before induction (n = 39), mean difference was -0.1 mmol/L (-0.6 to 0.4 mmol/L), and after induction (n = 39), mean difference was 0.1 mmol/L (-0.8 to 0.9 mmol/L). Further investigation showed the difference varied per test for patients receiving Sevoflurane compared to patients receiving TIVA (-0.2 ± 0.4 mmol/L vs. 0.4 ± 0.3 mmol/L, p < 0.001). Before and after induction, the difference between ACI II and hexokinase measurements increased for patients receiving Sevoflurane compared to patients receiving TIVA (0.4 ± 0.4 mmol/L vs. -0.4 ± 0.3 mmol/L, p < 0.001). CONCLUSION: The agreement between glucose measurements using ACI II and the reference laboratory hexokinase test was clinically acceptable with a percentage error of 10.0% (95% CI 8.0 to 11.9). The use of TIVA may negatively affect the measurement performance of the ACI II.

Unleashed Actin Assembly in Capping Protein-Deficient B16-F1 Cells Enables Identification of Multiple Factors Contributing to Filopodium Formation.

BACKGROUND: Filopodia are dynamic, finger-like actin-filament bundles that overcome membrane tension by forces generated through actin polymerization at their tips to allow extension of these structures a few microns beyond the cell periphery. Actin assembly of these protrusions is regulated by accessory proteins including heterodimeric capping protein (CP) or Ena/VASP actin polymerases to either terminate or promote filament growth. Accordingly, the depletion of CP in B16-F1 melanoma cells was previously shown to cause an explosive formation of filopodia. In Ena/VASP-deficient cells, CP depletion appeared to result in ruffling instead of inducing filopodia, implying that Ena/VASP proteins are absolutely essential for filopodia formation. However, this hypothesis was not yet experimentally confirmed. METHODS: Here, we used B16-F1 cells and CRISPR/Cas9 technology to eliminate CP either alone or in combination with Ena/VASP or other factors residing at filopodia tips, followed by quantifications of filopodia length and number. RESULTS: Unexpectedly, we find massive formations of filopodia even in the absence of CP and Ena/VASP proteins. Notably, combined inactivation of Ena/VASP, unconventional myosin-X and the formin FMNL3 was required to markedly impair filopodia formation in CP-deficient cells. CONCLUSIONS: Taken together, our results reveal that, besides Ena/VASP proteins, numerous other factors contribute to filopodia formation.

External Validation of Mortality Prediction Models for Critical Illness Reveals Preserved Discrimination but Poor Calibration.

OBJECTIVES: In a recent scoping review, we identified 43 mortality prediction models for critically ill patients. We aimed to assess the performances of these models through external validation. DESIGN: Multicenter study. SETTING: External validation of models was performed in the Simple Intensive Care Studies-I (SICS-I) and the Finnish Acute Kidney Injury (FINNAKI) study. PATIENTS: The SICS-I study consisted of 1,075 patients, and the FINNAKI study consisted of 2,901 critically ill patients. MEASUREMENTS AND MAIN RESULTS: For each model, we assessed: 1) the original publications for the data needed for model reconstruction, 2) availability of the variables, 3) model performance in two independent cohorts, and 4) the effects of recalibration on model performance. The models were recalibrated using data of the SICS-I and subsequently validated using data of the FINNAKI study. We evaluated overall model performance using various indexes, including the (scaled) Brier score, discrimination (area under the curve of the receiver operating characteristics), calibration (intercepts and slopes), and decision curves. Eleven models (26%) could be externally validated. The Acute Physiology And Chronic Health Evaluation (APACHE) II, APACHE IV, Simplified Acute Physiology Score (SAPS)-Reduced (SAPS-R)' and Simplified Mortality Score for the ICU models showed the best scaled Brier scores of 0.11' 0.10' 0.10' and 0.06' respectively. SAPS II, APACHE II, and APACHE IV discriminated best; overall discrimination of models ranged from area under the curve of the receiver operating characteristics of 0.63 (0.61-0.66) to 0.83 (0.81-0.85). We observed poor calibration in most models, which improved to at least moderate after recalibration of intercepts and slopes. The decision curve showed a positive net benefit in the 0-60% threshold probability range for APACHE IV and SAPS-R. CONCLUSIONS: In only 11 out of 43 available mortality prediction models, the performance could be studied using two cohorts of critically ill patients. External validation showed that the discriminative ability of APACHE II, APACHE IV, and SAPS II was acceptable to excellent, whereas calibration was poor.

Pharmacological Induction of Granulocyte Cell Death as Therapeutic Strategy.

Apoptosis is central for the maintenance of health. In the immune system, apoptosis guarantees proper development of immune cells and shutdown of immune reactions by the coordinated elimination of activated immune cells. Limitation of the life span of granulocytes is important, as overactivation of these cells is associated with chronic inflammation and collateral tissue damage. Consequently, targeted induction of granulocyte apoptosis may be beneficial in the course of respective immune disorders. Anti-inflammatory drugs such as glucocorticoids and monoclonal antibodies against IL-5Rα exert their function in part by triggering eosinophil apoptosis. Agonistic antibodies targeting Siglec-8 or death receptors are tested (pre)clinically. Moreover, a new class of inhibitors targeting antiapoptotic BCL-2 proteins shows great promise for anticancer treatments. Because of their specificity and tolerable side effects, these so-called BH3 mimetics may be worthwhile to evaluate in inflammatory disorders. Here, we review past and recent data on pharmacological apoptosis induction of granulocytes and highlight respective therapeutic potential.

Hexokinase 3 enhances myeloid cell survival via non-glycolytic functions.

The family of hexokinases (HKs) catalyzes the first step of glycolysis, the ATP-dependent phosphorylation of glucose to glucose-6-phosphate. While HK1 and HK2 are ubiquitously expressed, the less well-studied HK3 is primarily expressed in hematopoietic cells and tissues and is highly upregulated during terminal differentiation of some acute myeloid leukemia (AML) cell line models. Here we show that expression of HK3 is predominantly originating from myeloid cells and that the upregulation of this glycolytic enzyme is not restricted to differentiation of leukemic cells but also occurs during ex vivo myeloid differentiation of healthy CD34+ hematopoietic stem and progenitor cells. Within the hematopoietic system, we show that HK3 is predominantly expressed in cells of myeloid origin. CRISPR/Cas9 mediated gene disruption revealed that loss of HK3 has no effect on glycolytic activity in AML cell lines while knocking out HK2 significantly reduced basal glycolysis and glycolytic capacity. Instead, loss of HK3 but not HK2 led to increased sensitivity to ATRA-induced cell death in AML cell lines. We found that HK3 knockout (HK3-null) AML cells showed an accumulation of reactive oxygen species (ROS) as well as DNA damage during ATRA-induced differentiation. RNA sequencing analysis confirmed pathway enrichment for programmed cell death, oxidative stress, and DNA damage response in HK3-null AML cells. These signatures were confirmed in ATAC sequencing, showing that loss of HK3 leads to changes in chromatin configuration and increases the accessibility of genes involved in apoptosis and stress response. Through isoform-specific pulldowns, we furthermore identified a direct interaction between HK3 and the proapoptotic BCL-2 family member BIM, which has previously been shown to shorten myeloid life span. Our findings provide evidence that HK3 is dispensable for glycolytic activity in AML cells while promoting cell survival, possibly through direct interaction with the BH3-only protein BIM during ATRA-induced neutrophil differentiation.

The BCL-2 family member BOK promotes KRAS-driven lung cancer progression in a p53-dependent manner.

A variety of cancer entities are driven by KRAS mutations, which remain difficult to target clinically. Survival pathways, such as resistance to cell death, may represent a promising treatment approach in KRAS mutated cancers. Based on the frequently observed genomic deletions of BCL-2-related ovarian killer (BOK) in cancer patients, we explored the function of BOK in a mutant KrasG12D-driven murine model of lung cancer. Using KrasG12D/+ Bok-/- mice, we observed an overall tumor-promoting function of BOK in vivo. Specifically, loss of BOK reduced proliferation both in cell lines in vitro as well as in KrasG12D-driven tumor lesions in vivo. During tumor development in vivo, loss of BOK resulted in a lower tumor burden, with fewer, smaller, and less advanced tumors. Using KrasG12D/+ Tp53Δ/Δ Bok-/- mice, we identified that this phenotype was entirely dependent on the presence of functional p53. Furthermore, analysis of a human dataset of untreated early-stage lung tumors did not identify any common deletion of the BOK locus, independently of the TP53 status or the histopathological classification. Taken together our data indicate that BOK supports tumor progression in Kras-driven lung cancer.

A novel functional mast cell assay for the detection of allergies.

BACKGROUND: Clinical management of allergic diseases has been hampered by the lack of safe and convenient tests to reliably identify culprit allergens and to closely follow changes in disease activity over time. Because allergy diagnosis is a complex and laborious multistep procedure, there is an urgent need for simpler but still functionally accurate ex vivo assays allowing objective diagnosis, substantiating treatment choices, and quantifying therapeutic responses. OBJECTIVE: In this study, we sought to develop a novel functional cell-based assay that relies on passive sensitization of allergic effector cells with patient serum, circumventing current limitations in allergy diagnosis. METHODS: We genetically engineered a conditional homeobox B8 (Hoxb8)-immortalized progenitor line from the bone marrow of mice that are transgenic for the human high-affinity IgE receptor (FcεRIα). These cells can be reproducibly differentiated into mature Hoxb8 mast cells within 5 days of culture in virtually unlimited numbers. RESULTS: We demonstrate that the established Hoxb8 mast cell assay can be used to accurately measure total IgE levels, identify culprit allergens, longitudinally monitor allergen-specific immunotherapy, and potentially determine the time point of tolerance induction upon allergen-specific immunotherapy in patients with allergy. To facilitate the analysis of large testing volumes, we demonstrate a proof-of-concept for a high-throughput screening application based on fluorescent cell barcoding using the engineered Hoxb8 mast cells. CONCLUSIONS: Our results indicate that this novel mast cell assay could represent a valuable tool to support clinicians in the identification of IgE-mediated allergies and in the quantification of treatment efficacy as well as duration of therapeutic response.

Granule Leakage Induces Cell-Intrinsic, Granzyme B-Mediated Apoptosis in Mast Cells.

Mast cells are multifunctional immune cells scattered in tissues near blood vessels and mucosal surfaces where they mediate important reactions against parasites and contribute to the pathogenesis of allergic reactions. Serine proteases released from secretory granules upon mast cell activation contribute to these functions by modulating cytokine activity, platelet activation and proteolytic neutralization of toxins. The forced release of granule proteases into the cytosol of mast cells to induce cell suicide has recently been proposed as a therapeutic approach to reduce mast cell numbers in allergic diseases, but the molecular pathways involved in granule-mediated mast cell suicide are incompletely defined. To identify intrinsic granule proteases that can cause mast cell death, we used mice deficient in cytosolic serine protease inhibitors and their respective target proteases. We found that deficiency in Serpinb1a, Serpinb6a, and Serpinb9a or in their target proteases did not alter the kinetics of apoptosis induced by growth factor deprivation in vitro or the number of peritoneal mast cells in vivo. The serine protease cathepsin G induced marginal cell death upon mast cell granule permeabilization only when its inhibitors Serpinb1a or Serpinb6a were deleted. In contrast, the serine protease granzyme B was essential for driving apoptosis in mast cells. On granule permeabilization, granzyme B was required for caspase-3 processing and cell death. Moreover, cytosolic granzyme B inhibitor Serpinb9a prevented caspase-3 processing and mast cell death in a granzyme B-dependent manner. Together, our findings demonstrate that cytosolic serpins provide an inhibitory shield preventing granule protease-induced mast cell apoptosis, and that the granzyme B-Serpinb9a-caspase-3 axis is critical in mast cell survival and could be targeted in the context of allergic diseases.

Perioperative goal-directed therapy in high-risk abdominal surgery. A multicenter randomized controlled superiority trial.

STUDY OBJECTIVE: The potential of perioperative goal-directed therapy (PGDT) to improve outcome after high-risk abdominal surgery remains subject of debate. In particular, there is a need for large, multicenter trials focusing on relevant patient outcomes to confirm the evidence found in small, single center studies including minor complications in their composite endpoints. The present study therefore aims to investigate the effect of an arterial waveform analysis based PGDT algorithm on the incidence of major complications including mortality after high-risk abdominal surgery. DESIGN: Prospective randomized controlled multicenter trial. SETTING: Operating theatres and Post-Anesthesia/Intensive Care units (PACU/ICU) of four tertiary hospitals in The Netherlands. PATIENTS: A total number of 482 patients undergoing elective, abdominal surgery that is considered high-risk due to the extent of the procedure and/or patient comorbidities. INTERVENTIONS: Hemodynamic therapy using an age-specific PGDT algorithm including cardiac index (CI) and stroke volume variation (SVV) measurements during a 24-h perioperative period starting at induction of anesthesia. MEASUREMENTS: The average number of major complications (including mortality) within 30 days after surgery, the number of minor complications, hospital and PACU/ICU length of stay (LOS), amounts of fluids and vasoactive medications used. Complications were graded using the Accordion severity grading system. RESULTS: The average number of major complications per patient was 0.79 (PGDT group) versus 0.69 (control group) (p = 0.195). There were no statistically significant differences in the number of minor complications, hospital LOS, PACU/ICU LOS, or grading of complications. Patients in the PGDT group received more fluids intraoperatively, more dobutamine intra- and postoperatively, while patients in the control group received more phenylephrine during the operation. CONCLUSIONS: PGDT based on a CI and SVV driven algorithm did not result in improved outcomes after high-risk abdominal surgery. CLINICAL TRIAL REGISTRATION: Netherlands Trial Registry: NTR3380.

Identifying and characterizing high-risk clusters in a heterogeneous ICU population with deep embedded clustering.

Critically ill patients constitute a highly heterogeneous population, with seemingly distinct patients having similar outcomes, and patients with the same admission diagnosis having opposite clinical trajectories. We aimed to develop a machine learning methodology that identifies and provides better characterization of patient clusters at high risk of mortality and kidney injury. We analysed prospectively collected data including co-morbidities, clinical examination, and laboratory parameters from a minimally-selected population of 743 patients admitted to the ICU of a Dutch hospital between 2015 and 2017. We compared four clustering methodologies and trained a classifier to predict and validate cluster membership. The contribution of different variables to the predicted cluster membership was assessed using SHapley Additive exPlanations values. We found that deep embedded clustering yielded better results compared to the traditional clustering algorithms. The best cluster configuration was achieved for 6 clusters. All clusters were clinically recognizable, and differed in in-ICU, 30-day, and 90-day mortality, as well as incidence of acute kidney injury. We identified two high mortality risk clusters with at least 60%, 40%, and 30% increased. ICU, 30-day and 90-day mortality, and a low risk cluster with 25-56% lower mortality risk. This machine learning methodology combining deep embedded clustering and variable importance analysis, which we made publicly available, is a possible solution to challenges previously encountered by clustering analyses in heterogeneous patient populations and may help improve the characterization of risk groups in critical care.

Cognitive biases, environmental, patient and personal factors associated with critical care decision making: A scoping review.

PURPOSE: Cognitive biases and factors affecting decision making in critical care can potentially lead to life-threatening errors. We aimed to examine the existing evidence on the influence of cognitive biases and factors on decision making in critical care. MATERIALS AND METHODS: We conducted a scoping review by searching MEDLINE for articles from 2004 to November 2020. We included studies conducted in physicians that described cognitive biases or factors associated with decision making. During the study process we decided on the method to summarize the evidence, and based on the obtained studies a descriptive summary of findings was the best fit. RESULTS: Thirty heterogenous studies were included. Four main biases or factors were observed, e.g. cognitive biases, personal factors, environmental factors, and patient factors. Six (20%) studies reported biases associated with decision making comprising omission-, status quo-, implicit-, explicit-, outcome-, and overconfidence bias. Nineteen (63%) studies described personal factors, twenty-two (73%) studies described environmental factors, and sixteen (53%) studies described patient factors. CONCLUSIONS: The current evidence on cognitive biases and factors is heterogenous, but shows they influence clinical decision. Future studies should investigate the prevalence of cognitive biases and factors in clinical practice and their impact on clinical outcomes.

Loss of BOK Has a Minor Impact on Acetaminophen Overdose-Induced Liver Damage in Mice.

Acetaminophen (APAP) is one of the most commonly used analgesic and anti-pyretic drugs, and APAP intoxication is one of the main reasons for liver transplantation following liver failure in the Western world. While APAP poisoning ultimately leads to liver necrosis, various programmed cell death modalities have been implicated, including ER stress-triggered apoptosis. The BCL-2 family member BOK (BCL-2-related ovarian killer) has been described to modulate the unfolded protein response and to promote chemical-induced liver injury. We therefore investigated the impact of the loss of BOK following APAP overdosing in mice. Surprisingly, we observed sex-dependent differences in the activation of the unfolded protein response (UPR) in both wildtype (WT) and Bok-/- mice, with increased activation of JNK in females compared with males. Loss of BOK led to a decrease in JNK activation and a reduced percentage of centrilobular necrosis in both sexes after APAP treatment; however, this protection was more pronounced in Bok-/- females. Nevertheless, serum ALT and AST levels of Bok-/- and WT mice were comparable, indicating that there was no major difference in the overall outcome of liver injury. We conclude that after APAP overdosing, loss of BOK affects initiating signaling steps linked to ER stress, but has a more minor impact on the outcome of liver necrosis. Furthermore, we observed sex-dependent differences that might be worthwhile to investigate.

Sialic Acids and Their Influence on Human NK Cell Function.

Sialic acids are sugars with a nine-carbon backbone, present on the surface of all cells in humans, including immune cells and their target cells, with various functions. Natural Killer (NK) cells are cells of the innate immune system, capable of killing virus-infected and tumor cells. Sialic acids can influence the interaction of NK cells with potential targets in several ways. Different NK cell receptors can bind sialic acids, leading to NK cell inhibition or activation. Moreover, NK cells have sialic acids on their surface, which can regulate receptor abundance and activity. This review is focused on how sialic acids on NK cells and their target cells are involved in NK cell function.

Current use of inotropes in circulatory shock.

BACKGROUND: Treatment decisions on critically ill patients with circulatory shock lack consensus. In an international survey, we aimed to evaluate the indications, current practice, and therapeutic goals of inotrope therapy in the treatment of patients with circulatory shock. METHODS: From November 2016 to April 2017, an anonymous web-based survey on the use of cardiovascular drugs was accessible to members of the European Society of Intensive Care Medicine (ESICM). A total of 14 questions focused on the profile of respondents, the triggering factors, first-line choice, dosing, timing, targets, additional treatment strategy, and suggested effect of inotropes. In addition, a group of 42 international ESICM experts was asked to formulate recommendations for the use of inotropes based on 11 questions. RESULTS: A total of 839 physicians from 82 countries responded. Dobutamine was the first-line inotrope in critically ill patients with acute heart failure for 84% of respondents. Two-thirds of respondents (66%) stated to use inotropes when there were persistent clinical signs of hypoperfusion or persistent hyperlactatemia despite a supposed adequate use of fluids and vasopressors, with (44%) or without (22%) the context of low left ventricular ejection fraction. Nearly half (44%) of respondents stated an adequate cardiac output as target for inotropic treatment. The experts agreed on 11 strong recommendations, all of which were based on excellent (> 90%) or good (81-90%) agreement. Recommendations include the indications for inotropes (septic and cardiogenic shock), the choice of drugs (dobutamine, not dopamine), the triggers (low cardiac output and clinical signs of hypoperfusion) and targets (adequate cardiac output) and stopping criteria (adverse effects and clinical improvement). CONCLUSION: Inotrope use in critically ill patients is quite heterogeneous as self-reported by individual caregivers. Eleven strong recommendations on the indications, choice, triggers and targets for the use of inotropes are given by international experts. Future studies should focus on consistent indications for inotrope use and implementation into a guideline for circulatory shock that encompasses individualized targets and outcomes.