Characteristics and spectrum changes of PICU cases during the COVID-19 pandemic: a retrospective analysis.

Objective: This study aims to compare the changes in the disease spectrum of children admitted to the Pediatric Intensive Care Units (PICU) during the COVID-19 pandemic with the three years prior to the pandemic, exploring the impact of the COVID-19 pandemic on the disease spectrum of PICU patients. Methods: A retrospective analysis was conducted on critically ill children admitted to the PICU of Hunan Children's Hospital from January 2020 to December 2022, and the results were compared with cases from the same period between January 2017 and December 2019. The cases were divided into pre-pandemic period (January 2017-December 2019) with 8,218 cases, and pandemic period (January 2020-December 2022) with 5,619 cases. General characteristics, age, and gender were compared between the two groups. Results: Compared to the pre-pandemic period, there was a 31.62% decrease in the number of admitted children during the pandemic period, and a 52.78% reduction in the proportion of respiratory system diseases. The overall mortality rate decreased by 87.81%. There were differences in age and gender distribution between the two periods. The length of hospital stay during the pandemic showed no statistical significance, whereas hospitalization costs exhibited statistical significance. Conclusion: The COVID-19 pandemic has exerted a certain influence on the disease spectrum of PICU admissions. Implementing relevant measures during the pandemic can help reduce the occurrence of respiratory system diseases in children. Considering the changes in the disease spectrum of critically ill PICU children, future clinical prevention and treatment in PICUs should continue to prioritize the respiratory, neurological, and hematological oncology systems.

Development and validation of an early mortality risk model for pediatric hemophagocytic lymphohistiocytosis: a comparison with HScore, PELOD-2, P-MODS, and pSOFA.

There has been no severity evaluation model for pediatric patients with hemophagocytic lymphohistiocytosis (HLH) that uses readily available parameters. This study aimed to develop a novel model for predicting the early mortality risk in pediatric patients with HLH using easily obtained parameters whatever etiologic subtype. Patients from one center were divided into training and validation sets for model derivation. The developed model was validated using an independent validation cohort from the second center. The prediction model with nomogram was developed based on logistic regression. The model performance underwent internal and external evaluation and validation using the area under the receiver operating characteristic curve (AUC), calibration curve with 1000 bootstrap resampling, and decision curve analysis (DCA). Model performance was compared with the most prevalent severity evaluation scores, including the PELOD-2, P-MODS, and pSOFA scores. The prediction model included nine variables: glutamic-pyruvic transaminase, albumin, globulin, myohemoglobin, creatine kinase, serum potassium, procalcitonin, serum ferritin, and interval between onset and diagnosis. The AUC of the model for predicting the 28-day mortality was 0.933 and 0.932 in the training and validation sets, respectively. The AUC values of the HScore, PELOD-2, P-MODS and pSOFA were 0.815, 0.745, 0.659 and 0.788, respectively. The DCA of the 28-day mortality prediction exhibited a greater net benefit than the HScore, PELOD-2, P-MODS and pSOFA. Subgroup analyses demonstrated good model performance across HLH subtypes. The novel mortality prediction model in this study can contribute to the rapid assessment of early mortality risk after diagnosis with readily available parameters.

Recent progress on the development of bioinspired surfaces with high aspect ratio microarray structures: From fabrication to applications.

Surfaces with high aspect ratio microarray structures can implement sophisticated assignment in typical fields including microfluidics, sensor, biomedicine, et al. via regulating their deformation or the material properties. Inspired by natural materials and systems, for example sea cockroaches, water spiders, cacti, lotus leaves, rice leaves, and cedar leaves, many researchers have focused on microneedle functional surface studies. When the surface with high aspect ratio microarray structures is stimulated by the external fields, such as optical, electric, thermal, magnetic, the high aspect ratio microarray structures can undergo hydrophilic and hydrophobic switching or shape change, which may be gifted the surfaces with the ability to perform complex task, including directional liquid/air transport, targeted drug delivery, microfluidic chip sensing. In this review, the fabrication principles of various surfaces with high aspect ratio microarray structures are classified and summarized. Mechanisms of liquid manipulation on hydrophilic/hydrophobic surfaces with high aspect ratio microarray structures are clarified based on Wenzel model, Cassie model, Laplace pressure theories and so on. Then the intelligent control strategies have been demonstrated. The applications in microfluidic, drug delivery, patch sensors have been discussed. Finally, current challenges and new insights of future prospects for dynamic manipulation of liquid/air based on biomimetic surface with high aspect ratio microarray structures are also addressed.

[Value of complement component 3 in predicting the prognosis of children with sepsis]. / 补体C3å¯¹å„¿ç«¥è„“æ¯’ç—‡æ‚£è€ é¢„åŽçš„é¢„æµ‹ä»·å€¼.

OBJECTIVES: To investigate changes in complement component 3 (C3) levels in children with sepsis and its correlation with the severity of sepsis and to explore the significance of C3 in predicting mortality in children with sepsis. METHODS: A retrospective analysis was conducted on 529 children with sepsis who were admitted to the Pediatric Intensive Care Unit in Hunan Children's Hospital between November 2019 and September 2021. The children were categorized into two groups based on their prognosis at day 28 after sepsis diagnosis: the survival group (n=471) and the death group (n=58). Additionally, the children were divided into normal C3 group (n=273) and reduced C3 group (n=256) based on the median C3 level (0.77 g/L) within 24 hours of admission. Clinical data and laboratory markers were compared between the groups, and assess the predictive value of C3 levels in relation to sepsis-related mortality. RESULTS: The death group exhibited significantly lower C3 levels compared to the survival group (P<0.05). Multivariate logistic regression analysis revealed that higher pediatric Sequential Organ Failure Assessment (p-SOFA) scores and lower C3 levels were closely associated with sepsis-related mortality (P<0.05). The receiver operating characteristic curve (ROC) analysis demonstrated that combination of p-SOFA scores and C3 levels yielded an area under the ROC curve of 0.852, which was higher than that of each indicator alone (P<0.05). CONCLUSIONS: C3 can serve as an indicator to assess the severity and prognosis of sepsis in children. The combination of p-SOFA scores and C3 levels holds good predictive value for mortality in children with sepsis.

Proteomic Analysis of Pediatric Hemophagocytic Lymphohistiocytosis: a Comparative Study with Healthy Controls, Sepsis, Critical Ill, and Active Epstein-Barr virus Infection to Identify Altered Pathways and Candidate Biomarkers.

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammatory syndrome characterized by excessive activation of the immune system, along with uncontrolled proliferation of activated macrophages and lymphocytes. The clinical features of HLH often overlap with the clinical features of other severe inflammatory conditions such as sepsis, hindering accurate and timely diagnosis. In this study, we performed a data-independent acquisition mass spectrometry-based plasma proteomic analysis of 33 pediatric patients with HLH compared with four control groups: 39 healthy children, 43 children with sepsis, 39 children hospitalized in the pediatric intensive care unit without confirmed infections, and 21 children with acute Epstein-Barr virus infection. Proteomic comparisons between the HLH group and each of the control groups showed that HLH was characterized by alterations in complement and coagulation cascades, neutrophil extracellular trap formation, and platelet activation pathways. We identified eight differentially expressed proteins in patients with HLH, including plastin-2 (LCP1), vascular cell adhesion protein 1, fibrinogen beta chain, fibrinogen gamma chain, serum amyloid A-4 protein, extracellular matrix protein 1, apolipoprotein A-I, and albumin. LCP1 emerged as a candidate diagnostic marker for HLH with an area under the curve (AUC) of 0.97 in the original cohort and an AUC of 0.90 (sensitivity = 0.83 and specificity = 1.0) in the validation cohort. Complement C1q subcomponent subunit B was associated with disease severity in patients with HLH. Based on comparisons with multiple control groups, this study provides a proteomic profile and candidate biomarkers of HLH, offering researchers novel information to improve the understanding of this condition.

Clinical characteristics and outcomes of children with Kawasaki disease combined with sepsis in the pediatric intensive care unit.

Background: Kawasaki disease (KD) is a vascular inflammatory disease with unknown pathogenesis. There are few studies on KD combined with sepsis worldwide. Purpose: To provide valuable data regarding clinical characteristics and outcomes related to pediatric patients with KD combined with sepsis in pediatric intensive care unit (PICU). Methods: We retrospectively analyzed the clinical data of 44 pediatric patients admitted in PICU at Hunan Children's Hospital with KD combined with sepsis between January 2018 and July 2021. Results: Of the 44 pediatric patients (mean age, 28.18 ± 24.28 months), 29 were males and 15 were female. We further divided the 44 patients into two groups: KD combined with severe sepsis (n=19) and KD combined with non-severe sepsis (n=25). There were no significant between-group differences in leukocyte, C-reactive protein, and erythrocyte sedimentation rate. Interleukin-6, interleukin-2, interleukin-4 and procalcitonin in KD with severe sepsis group were significantly higher than those in KD with non-severe sepsis group. And the percentage of suppressor T lymphocyte and natural killer cell in severe sepsis group were significantly higher than those in non-severe group, while the CD4+/CD8+ T lymphocyte ratio was significantly lower in KD with severe sepsis group than in KD with non-severe sepsis group. All 44 children survived and were successfully treated after intravenous immune globulin (IVIG) combined with antibiotics. Conclusion: Children who develop with KD combined with sepsis have different degrees of inflammatory response and cellular immunosuppression, and the degree of inflammatory response and cellular immunosuppression is significantly correlated with the severity of the disease.

Decreased NK cells in cases of severe adenovirus pneumonia with liver dysfunction in pediatric intensive care unit: Evidence from 330 patients.

BACKGROUND: Although the human adenovirus infection is common, adenovirus infection with liver dysfunction is rare. METHODS: To retrospectively analyze and compare the clinical characteristics and outcomes of pediatric patients diagnosed with severe adenovirus pneumonia with and without liver dysfunction, who were admitted to the pediatric intensive care unit of Hunan Children's Hospital (South China University) between January 2018 and June 2022. RESULTS: Of the 330 severe adenovirus pneumonia cases analyzed (mean age, 19.88 ± 18.26 months), 102 were girls and 228 were boys. They were divided into two groups: those with liver dysfunction (n = 54) and without liver dysfunction (n = 276). Comparison analysis showed no significant between-group differences in body mass index and levels of white blood cells, neutrophils, platelets, albumin, total bilirubin, direct bilirubin, indirect bilirubin, creatine kinase, procalcitonin, creatinine, and urea nitrogen. However, the levels of alanine aminotransferase (175.99 U/L vs 30.55 U/L) and aspartate transaminase (215.96 U/L vs 74.30 U/L) were significantly higher in patients with liver dysfunction compared to those without liver dysfunction. Further analysis showed that pediatric patients with liver dysfunction had a significantly lower percentage of natural killer (NK) cells (6.93% vs 8.71%) and higher mortality rate (22% vs 9%) than those without liver dysfunction. CONCLUSION: A decrease in serum NK cell levels in pediatric patients with severe adenovirus pneumonia could serve as a marker for monitoring the onset or progression of hepatic damage.

Decreased NK cells in cases of severe adenovirus pneumonia with liver dysfunction in pediatric intensive care unit: Evidence from 330 patients

Background: Although the human adenovirus infection is common, adenovirus infection with liver dysfunction is rare. Methods: To retrospectively analyze and compare the clinical characteristics and outcomes of pediatric patients diagnosed with severe adenovirus pneumonia with and without liver dysfunction, who were admitted to the pediatric intensive care unit of Hunan Children’s Hospital (South China University) between January 2018 and June 2022. Results: Of the 330 severe adenovirus pneumonia cases analyzed (mean age, 19.88 ± 18.26 months), 102 were girls and 228 were boys. They were divided into two groups: those with liver dysfunction (n = 54) and without liver dysfunction (n = 276). Comparison analysis showed no significant between-group differences in body mass index and levels of white blood cells, neutrophils, platelets, albumin, total bilirubin, direct bilirubin, indirect bilirubin, creatine kinase, procalcitonin, creatinine, and urea nitrogen. However, the levels of alanine aminotransferase (175.99 U/L vs 30.55 U/L) and aspartate transaminase (215.96 U/L vs 74.30 U/L) were significantly higher in patients with liver dysfunction compared to those without liver dysfunction. Further analysis showed that pediatric patients with liver dysfunction had a significantly lower percentage of natural killer (NK) cells (6.93% vs 8.71%) and higher mortality rate (22% vs 9%) than those without liver dysfunction. Conclusion: A decrease in serum NK cell levels in pediatric patients with severe adenovirus pneumonia could serve as a marker for monitoring the onset or progression of hepatic damage (AU)

A Three-Step Screening Procedure for Early Identification of Children at High Risk of Hemophagocytic Lymphohistiocytosis.

PURPOSE: The first step in diagnosing hemophagocytic lymphohistiocytosis (HLH) is to suspect its presence and then order the appropriate diagnostic tests. The development of screening procedures for HLH could facilitate early diagnosis. In this study, we evaluated the utility of fever, splenomegaly, and cytopenias as screening criteria for identifying pediatric HLH at an early stage, built a screening model using commonly measured laboratory parameters, and developed a step-wise screening procedure for pediatric HLH. METHODS: The medical records of 83,965 pediatric inpatients, including 160 patients with HLH, were collected retrospectively. The utility of fever, splenomegaly, hemoglobin level, and platelet and neutrophil counts at hospital admission as screening criteria for HLH was evaluated. For HLH patients who might be missed by screening based on the presence of fever, splenomegaly, and cytopenias, a screening model using common laboratory parameters was developed. Following that, a three-step screening procedure was then developed. RESULTS: The criteria of cytopenias affecting two or more lineages plus fever or splenomegaly had a sensitivity of 51.9% and a specificity of 98.4% for identifying HLH in pediatric inpatients. Our screening score model comprises six parameters: splenomegaly, platelet count, neutrophil count, albumin level, total bile acid level, and lactate dehydrogenase level. The use of the validation set had a sensitivity of 87.0% and a specificity of 90.6%. A three-step screening procedure has been developed: Step 1: Is fever or splenomegaly present? (Yes: risk for HLH should be considered, go to Step 2; No: less likely HLH); Step 2: Are cytopenias affecting at least two lineages? (Yes: consider HLH; No: go to Step 3); Step 3: Calculate the screening score. Is the sum of the score greater than 37? (Yes: consider HLH; No: less likely HLH). The overall sensitivity and specificity of the three-step screening procedure were 91.9% and 94.4%, respectively. CONCLUSION: A significant proportion of pediatric HLH patients present at the hospital without having all three symptoms: fever, splenomegaly, and cytopenias. Our three-step screening procedure, utilizing commonly available clinical and laboratory parameters, can effectively identify pediatric patients who may be at high risk for HLH.

Effects of Grinding Parameters on the Processing Temperature, Crack Propagation and Residual Stress in Silicon Nitride Ceramics.

The surface/subsurface damage of engineering ceramics after machining has a great influence on the service performance of parts. In order to obtain a high grinding surface quality of engineering ceramics, and take silicon nitride ceramic as a research object, a series of grinding experiments were carried out. The effects of grinding parameters on longitudinal crack propagation depth and the surface residual stress of silicon nitride ceramics were analyzed by grinding experiments, and the residual stress at the location of crack propagation was obtained. The variation in the grinding temperature under different grinding parameters was explored. The influences of the grinding temperature on crack propagation depth and surface residual stress were clarified, the distribution of residual stress along the depth direction was discussed, and the relationship between the residual stress and crack propagation was revealed. The results show that the residual compressive stress on the surface of silicon nitride ceramics decreases with the increase in the depth of crack propagation and the degree of surface brittle spalling. The residual stress at the location of the crack propagation was residual tensile stress. The crack propagation depth increased with the increase in the residual tensile stress. The research provides a reference for the realization of high-quality surfaces in the grinding of silicon nitride ceramics.

Poly(arylene ether)s-Based Polymeric Membranes Applied for Water Purification in Harsh Environment Conditions: A Mini-Review.

Confronting the pressing challenge of freshwater scarcity, polymeric membrane-based water treatment technology has emerged as an essential and effective approach. Poly(arylene ether)s (PAEs) polymers, a class of high-performance engineering thermoplastics, have garnered attention in recent decades as promising membrane materials for advanced water treatment approaches. The PAE-Based membranes are employed to resist the shortages of most common polymeric membranes, such as chemical instability, structural damage, membrane fouling, and shortened lifespan when deployed in harsh environments, owing to their excellent comprehensive performance. This article presents the advancements in the research of several typical PAEs, including poly(ether ether ketone) (PEEK), polyethersulfone (PES), and poly(arylene ether nitrile) (PEN). Techniques for membrane formation, modification strategies, and applications in water treatment have been reviewed. The applications encompass processes for oil/water separation, desalination, and wastewater treatment, which involve the removal of heavy metal ions, dyes, oils, and other organic pollutants. The commendable performance of these membranes has been summarized in terms of corrosion resistance, high-temperature resistance, anti-fouling properties, and durability in challenging environments. In addition, several recommendations for further research aimed at developing efficient and robust PAE-based membranes are proposed.

[Research progress on the role of nuclear factor erythroid 2-related factor 2 in ferroptosis of sepsis].

Sepsis is a life-threatening organ dysfunction caused by the disorder of the body's response to infection, and is one of the main causes of death in critically ill patients. Ferroptosis is a kind of iron dependent cell death, characterized by intracellular reactive oxygen species (ROS) accumulation. Sepsis can cause a substantial accumulation of ROS in cells. The transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) is a key regulator of antioxidant and plays a critical protective role in sepsis induced ferroptosis by regulating the expression of proteins related to the ferroptosis pathway. Current studies have found that activation of Nrf2 has a protective effect on ferroptosis induced by sepsis. In this paper, we summarized the regulation mechanism of Nrf2 in ferroptosis, in order to provide references for the treatment of sepsis.

Single-Cell Transcriptional Profiling Reveals Low-Level Tragus Stimulation Improves Sepsis-Induced Myocardial Dysfunction by Promoting M2 Macrophage Polarization.

Background: Sepsis can lead to multiple organ damage, of which the heart is one of the most vulnerable organs. Vagal nerve stimulation can reduce myocardial injury in sepsis and improve survival rates. However, the potential impact of low-level tragus stimulation and disparate cell populations on sepsis-induced myocardial dysfunction remains undetermined. Methods: A cardiac single-cell transcriptomic approach was used for characterizing cardiac cell populations that form the heart. Single-cell mRNA sequencing data were used for selecting all cardiac macrophages from CD45+ cells. Then, echocardiography, western blot, flow cytometry, immunofluorescence, and immunohistochemistry were performed to verify the single-cell mRNA sequencing results. Results: Using single-cell mRNA sequencing data, we uncovered the multiple cell populations contributing to myocardial injury in sepsis under low-level tragus stimulation, thereby illustrating a comprehensive map of the cardiac cellular landscape. Pseudotiming analysis in single-cell sequencing showed that low-level vagal nerve stimulation played an anti-inflammatory role by promoting cardiac monocytes into M2 macrophages, which significantly increased α7nAChR expression in heart tissues. Echocardiography assessment indicated that low-level vagal nerve stimulation could also improve cardiac functions in mice with sepsis-induced myocardial dysfunction. In addition, the heart tissues of mice from the sepsis group with low-level tragus stimulation had significantly lower interleukin-1ß expression levels than those from the sepsis group. Flow cytometry analysis showed that different acetylcholine concentrations promoted cardiac monocytes into M2 macrophages in in vitro experiments. Conclusion: Low-level tragus stimulation could improve sepsis-induced myocardial dysfunction by promoting cardiac monocytes to M2 macrophages.

Development of a screening score for Hemophagocytic Lymphohistiocytosis among pediatric patients with acute infection of Epstein-Barr virus.

Background and aims: Deciding when to suspect hemophagocytic lymphohistiocytosis (HLH) and perform diagnostic tests in patients with acute infection of Epstein-Barr virus (EBV) is challenging, given the high prevalence of EBV infection, the life-threatening risk of EBV-HLH, the relatively low incidence of EBV-HLH, and the wide spectrum of disease presentations. The aim of this study was to develop an EBV-HLH screening model for pediatric patients diagnosed with acute infection of EBV. Methods: An inpatient cohort with 3183 pediatric patients who were diagnosed with active infection of EBV was used to construct and validate the EBV-HLH screening score model. The model parameters were selected from common laboratory parameters using the method of Akaike Information Criterion-optimal selection through cross-validation under logistic regression. Performance of the score was evaluated and compared with the performance of screening methods using the number of cytopenias lineages. Results: The EBV-HLH screening score has five parameters, including hemoglobin, platelet, neutrophil, albumin, and lactate dehydrogenase. Using a cut-of value of 29, the scoring model had a sensitivity of 89.2% and a specificity of 89.5% in the validation set. The false negative rate, false positive rate, positive predictive value, and negative predictive value in the validation set was 10.8%, 10.5%, 26.8%, and 99.5%, respectively, similar to that of the training set. Conclusions: With five common laboratory parameters, the EBV-HLH score provides a simple tool to assist the identification of EBV patients who require further evaluation of HLH. Further studies are needed to evaluate the generalizability of the score and optimize the diagnose process for EBV-HLH.

Fulfillment status of hypertriglyceridemia and hypofibrinogenemia in children with hemophagocytic lymphohistiocytosis and risks of multiple organ dysfunction syndrome and early mortality.

BACKGROUND: Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening disorder. How to stratify high risk patients is one of the current challenges for the treatment of HLH. HLH patients usually fulfill multiple but not all eight diagnostic criteria. Different combinations of the fulfilled criteria may naturally cluster into previously undescribed subsets or phenotypes that may have different pathophysiology and demonstrate different risks for a poor outcome. The objectives of this study were to identify HLH subgroups according to the fulfillment of diagnostic criteria and evaluate the risk of multiple organ dysfunction syndrome (MODS) and 30-day mortality for subgroups. We retrospectively collect medical records of patients with discharge diagnosis of HLH between June 2015 and October 2018 from a tertiary children's hospital in China. Latent class analysis was used to identify class defining variables from HLH diagnostic items, and subgroups were defined according to different combinations of the class defining variables. RESULTS: Triglyceride and fibrinogen were identified as the class defining variables. When evaluated in combinations, patients with hypertriglyceridemia and normal fibrinogen levels during hospitalization had the lowest risks for MODS (27.8%, OR = 1) and 30-day mortality (18.8%, OR = 1), and patients with normal triglyceride and hypofibrinogenemia had the highest risks for MODS (86.2%, OR = 16.24, P = 0.0002) and 30-day mortality (57.1%, OR = 5.78, P = 0.0187). The fulfillment status of hypertriglyceridemia and hypofibrinogenemia within 72 h of hospital admission was also associated with the risk of adverse outcomes. CONCLUSIONS: The fulfillment status of hypertriglyceridemia and hypofibrinogenemia were associated with the risks of MODS and 30-day mortality among pediatric HLH patients. Further studies are needed to validate this association and investigate its clinical utility in the severity evaluation for HLH.

Proteomic analysis identified potential age-associated prognostic biomarkers in pneumonia-derived paediatric sepsis.

PURPOSE: Our aim was to investigate the age-associated plasma protein profiles in pneumonia-derived sepsis between infants and toddlers and identify potential age-adapted prognostic markers for poor outcome of pneumonia-derived pediatric sepsis. EXPERIMENTAL DESIGN: A nested case-control study strategy was applied. The plasma proteomes of pneumonia-derived pediatric septic patients with different outcomes between infants and toddlers were respectively analysed compared to their age-matched controls. RESULTS: Compared to toddlers, pneumonia-derived sepsis in infants was characterized by increased upregulation of protein processing in the ER, proteasome and antigen processing and presentation; and reduced downregulation in complement and coagulation cascades and cholesterol metabolism. Among them, the pentose phosphate pathway as well as the complement and coagulation cascades were possibly associated with poor outcome of pneumonia-derived sepsis. Furthermore, we confirmed that HP, THBS1, and SAA1/2 were potential prognostic markers for poor outcome of pneumonia-derived sepsis in infant patient groups. CONCLUSIONS AND CLINICAL RELEVANCE: Age-associated plasma protein profiles of pneumonia-derived pediatric septic patients provided potential age-adapted biomarkers for a more precise prognosis of poor outcome in pneumonia-derived pediatric sepsis and helped to improve the survival of septic children.

Diagnostic Time Lag of Pediatric Haemophagocytic Lymphohistiocytosis and Patient Characteristics: A Retrospective Cohort Study.

The difficulties and challenges of applying the HLH-2004 diagnostic criteria to early identification and diagnosis of haemophagocytic lymphohistiocytosis have been fully addressed in previous studies. However, the distribution of the diagnostic time lag of haemophagocytic lymphohistiocytosis and related patient characteristics remain unclear. This study investigated the time lags between symptom onset and diagnosis and between hospital admission and diagnosis among pediatric patients with haemophagocytic lymphohistiocytosis, and identified factors that associated with a shorter or longer diagnostic time lag. The cohort of patients with haemophagocytic lymphohistiocytosis was drawn from a tertiary children's hospital and consisted of 122 pediatric patients. The distributions of symptom-to-diagnosis and admission-to-diagnosis time lags were assessed. Clinical characteristics within 48 h of admission and the fulfillment of HLH-2004 diagnostic criteria were compared among admission-to-diagnosis time lag categories. Logistic regression analyses were conducted to identify factors associated with an admission-to-diagnosis time lag >3 days. The median interval from first symptom onset to HLH diagnosis was 12 days (range 4-71 days) and the median interval from hospital admission to HLH diagnosis was 2 days (range 0-23 days). The following factors were negatively associated with admission-to-diagnosis > 3 days: Epstein-Barr virus infection; admission through pediatric intensive care unit; diagnosis established without NK-cell activity and soluble CD25 tests; the performance of all readily available diagnostic tests for HLH (within 48 and 72 h); concurrent fever, splenomegaly, and cytopenias within 48 h; hemophagocytosis, hypertriglyceridemia and/or hypofibrinogenemia within 48 h; and elevated ferritin, total bilirubin, alanine aminotransferase, and prothrombin time within 48 h. Our findings suggest that performance of adequate diagnostic tests for HLH is essential for early diagnosis of HLH. Once suspected, immediate and adequate diagnostic tests for HLH should be arranged for PICU patients. Improvements in diagnostic procedures and monitoring plans are needed to promote early diagnosis of HLH.

Integrin α4ß1/VCAM-1 Interaction Evokes Dynamic Cell Aggregation Between Immune Cells and Human Lung Microvascular Endothelial Cells at Infectious Hemolysis.

Bacterial and viral infection is a common cause of pneumonia, respiratory failure, and even acute respiratory distress syndrome. Increasing evidence indicates that red blood cells (RBCs) may contribute to immune response and inflammation. However, the precise molecular mechanisms that link RBC and hemolysis to the development and progression of inflammatory pathologies are not entirely understood. In this study, we used bacterial endotoxin, lipopolysaccharide (LPS), to mimic an infectious hemolysis and found that RBCs dynamically regulated cell aggregation between immune cells and human lung microvascular endothelial cells (HLMVEC). When RBCs were treated with LPS, integrin α4ß1 was increased and was accompanied by cytokines and chemokines release (TNF-α, IL-1ß, IL-6, IL-8, IFN-γ, CXCL12, CCL5, CCL7 and CCL4). Upon α4ß1 elevation, RBCs not only facilitated mature monocyte derived dendritic cell (mo-DCs) adhesion but also promoted HLMVEC aggregation. Furthermore, co-culture of the supernatant of LPS pre-treated RBCs with mo-DCs could promote naïve CD4 T cell proliferation. Notably, the filtered culture from LPS-lysed RBCs further promoted mo-DCs migration in a concentration dependent manner. From a therapeutic perspective, cyclic peptide inhibitor of integrin α4ß1 combined with methylprednisolone (α4ß1/Methrol) remarkably blocked RBCs aggregation to mo-DCs, HLMVEC, or mo-DCs and HLMVEC mixture. Moreover, α4ß1/Methrol dramatically reduced mo-DCs migration up-regulated glucocorticoid-induced leucine zipper in mo-DCs, and ultimately reversed immune cell dysfunction induced by hemolysis. Taken together, these results indicate that integrin α4ß1 on RBCs could mediate cell-cell interaction for adaptive immunity through influencing cell adhesion, migration, and T cell proliferation.

Changes in pediatric healthcare utilization in Hunan Province, China, during the COVID-19 pandemic: a multi-center cross-sectional study.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic brought remarkable disruption to the ways in which healthcare was delivered. This study aimed to examine changes in pediatric healthcare utilization in Hunan Province, China, during the COVID-19 pandemic. METHODS: An electronic survey was conducted among 142 hospitals in Hunan Province, China. Using data from January 1 to April 30, 2019 as a reference, the changes in the number of visits for different types of pediatric healthcare between January 1 and April 30, 2020 were calculated. Changes in the number of admissions for infections and injuries were also evaluated. RESULTS: The total number of pediatric healthcare presentations decreased by 53.3% in the first four months of 2020. The most remarkable reductions were observed in the utilization of emergency room (ranging from -45.7% to -94.9% among three hospital levels) and observation room (-55.8% to -77.7%); neonatal inpatient care experienced the smallest decreases (-21.2% to -25.5%). Approximately 85% of the total reduction in the number of pediatric inpatient admissions was attributable to the reduction in admissions for infections. A 13.3% increase in the number of admissions for injuries was observed among third-level hospitals. CONCLUSIONS: The utilization of all types of pediatric healthcare services in Hunan Province declined markedly after the outbreak of COVID-19. The reasons, consequences, and responses to these changes should be addressed in future studies and actions.

High-throughput phenotyping analysis of maize at the seedling stage using end-to-end segmentation network.

Image processing technologies are available for high-throughput acquisition and analysis of phenotypes for crop populations, which is of great significance for crop growth monitoring, evaluation of seedling condition, and cultivation management. However, existing methods rely on empirical segmentation thresholds, thus can have insufficient accuracy of extracted phenotypes. Taking maize as an example crop, we propose a phenotype extraction approach from top-view images at the seedling stage. An end-to-end segmentation network, named PlantU-net, which uses a small amount of training data, was explored to realize automatic segmentation of top-view images of a maize population at the seedling stage. Morphological and color related phenotypes were automatic extracted, including maize shoot coverage, circumscribed radius, aspect ratio, and plant azimuth plane angle. The results show that the approach can segment the shoots at the seedling stage from top-view images, obtained either from the UAV or tractor-based high-throughput phenotyping platform. The average segmentation accuracy, recall rate, and F1 score are 0.96, 0.98, and 0.97, respectively. The extracted phenotypes, including maize shoot coverage, circumscribed radius, aspect ratio, and plant azimuth plane angle, are highly correlated with manual measurements (R2 = 0.96-0.99). This approach requires less training data and thus has better expansibility. It provides practical means for high-throughput phenotyping analysis of early growth stage crop populations.