Vascular endothelial growth factor a modified mRNA engineered cellular electrospun membrane complexes promotes mouse skin wound repair.

Artificial skin substitutes are one of the most promising areas of wound healing research; however, graft survival largely depends on how the treatment is performed. Early angiogenesis is essential for wound healing and graft survival and vascular endothelial growth factor A (VEGFA) is an important cytokine that stimulates angiogenesis. Here, we first investigated the effects of different ratios of collagen (BC) and gelatin blended with poly (l-lactide-co-caprolactone) (PLCL) on nanofibrous membranes. The Young's modulus and cell proliferation were significantly higher in the 50% BC group than that in all other groups. Then, cellular electrospun membrane complexes (CEMC) were successfully constructed from nanoscaffolds and fibroblasts extracted from human foreskin and engineered with controlled autocrine VEGFA by transfecting VEGFA modified mRNA (modRNA). Engineered CEMC significantly promoted wound healing in vivo and contributed to stable vascular network formation in the grafted area, thereby increasing the survival rate of the engineered skin. This study provides a potential solution for wound healing while establishing the value of different RNA modification methods for various engineered skins in the future, thereby advancing engineered skin development.

Risk factors of pediatric venoarterial extracorporeal membrane oxygenation-related gastrointestinal bleeding after open-heart surgeries.

OBJECTIVE: To analyze the risk factors for gastrointestinal (GI) bleeding in congenital heart disease (CHD) patients supported with venoarterial extracorporeal membrane oxygenation (V-A ECMO) after open-heart surgery. METHODS: A retrospective analysis was performed on children with (GI group: 26 cases) and without (control group: 122 cases) GI bleeding during ECMO at Shanghai Children's Medical Center from 2017 to 2020. Clinical data were analyzed and compared between groups to search for risk factors for GI bleeding. RESULTS: A total of 148 cases were included in the study. The overall incidence of GI bleeding was 17.6% (26/148). The in-hospital mortality rate in the GI group was 61.5% (16/26) versus 45.9% (56/122) in the control group. Twenty-six patients suffered cardiac arrest before ECMO support. The GI bleeding incidence among extracorporeal cardiopulmonary resuscitation (ECPR) patients was 50.0% (13/26) versus 28.7 (35/122) among non-ECPR patients, p = 0.035. The activated clotting time (ACT) was 201.40 s (180.47 to 247.27) in the GI group versus 177.63 s (167.79 to 203.13) (p = 0.050) in the control group. The lowest antithrombin level (Min AT) was 27.00 ± 13.07% versus 37.62 ± 15.18 (p = 0.001). The pH and lactate levels before ECMO (Pre PH and Pre Lac) were lower in the GI group than in the control group. (7.31 ± 0.23 vs. 7.35 ± 0.17, p = 0.035 and 12.2 ± 6.11 vs. 7.78 ± 6.67, p = 0.003). Liver function during ECMO support was statistically worse in the GI group than in the control group. Multivariate analysis showed that Pre Lac (OR = 1.106 [1.018-1.202], p = 0.0016) was an independent risk factor for GI bleeding. ROC analysis of Pre Lac and GI bleeding showed an area under the curve (AUC) of 0.700 (95% CI: 0.600-0.800, p = 0.002) and a cutoff value of 9.30 mmol/L (sensitivity, 73.1%; specificity, 62.7%). CONCLUSIONS: As the first study in this field, the probability of GI bleeding and related mortality was found to be high in children supported with V-A ECMO after open-heart surgery. A higher lactate level before ECMO was an independent risk factor for GI bleeding.

Risk Factors of Venoarterial Extracorporeal Membrane Oxygenation-Related Intracranial Hemorrhage in Children with Congenital Heart Disease.

To analyze the risk factors for intracranial hemorrhage (ICH) in congenital heart disease (CHD) patients supported with venoarterial extracorporeal membrane oxygenation (VA-ECMO). We performed a retrospective analysis of VA ECMO patients after open heart surgery in Shanghai Children's Medical Center from February 2017 to December 2018, with a total of 50 patients: 14 patients in the ICH group and 36 patients in the control group. Clinical data were analyzed and compared between groups to search for risk factors for ICH. The overall incidence of ICH was 28% (14/50). The in-hospital mortality rate of the ICH group was 57.1% (8/14) vs. 58.3% (21/36) in the control group. The proportion of neonates in the ICH group was 64.3% (9/14) vs. 25% in the control group (9/36) (p = 0.009), and the ICH incidence in extracorporeal cardiopulmonary resuscitation (ECPR) patients was 64.3% (9/14) vs. 13.9% (5/36) (p = 0.000). The percentage of selective cerebral perfusion in the ICH group was 64.3% (9/14) vs. 16.7% (6/36) (p = 0.001) in the control group, and the maximum procalcitonin (PCT) was 43.70 ± 30.48 ng/ml in the ICH group versus 26.92 ± 23.28 ng/ml (p = 0.050) in the control group. Multivariate analysis showed that neonates (odds ratio [OR] = 6.47 [1.09-38.46]), ECPR use (OR = 7.48 [1.26-44.41]), and maximum PCT values (OR = 1.04 [1.001-1.070]) were independent risk factors for ICH. The probability of ICH remains high in children supported with VA-ECMO after cardiac surgery. Neonatal patients, ECPR use, and PCT peak values are independent risk factors for ICH.

Postcardiotomy Extracorporeal Membrane Oxygenation in Neonates.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) provides circulatory support in children with congenital heart disease, particularly in the setting of cardiopulmonary failure and inability to wean from cardiopulmonary bypass. This study summarized the clinical application of ECMO in the treatment of heart failure after cardiac surgery in neonates. MATERIALS AND METHODS: Clinical data of 23 neonates who received ECMO support in our center from January 2017 to June 2019 were retrospectively analyzed. RESULTS: Twenty-three neonates, aged from 0 to 25 days and weight between 2,300 and 4,500 g, with heart failure postcardiotomy were supported with ECMO. The successful weaning rate was 78.26% and discharge rate was 52.17%. Bleeding and residual malformation were the most common complications. The univariate analysis showed that nonsurvivors were related to the factors such as higher lactate value of ECMO 12 and 24 hours (p = 0.008 and 0.001, respectively), longer time to lactate normalization (p = 0.001), lactate > 10 mmol/L before ECMO (p = 0.01), lower weight (p = 0.01), longer ECMO duration (p = 0.005), lower platelet count (p = 0.001), more surgical site bleeding (p = 0.001), and surgical residual malformation (p = 0.04). Further logistic regression analysis revealed that higher lactate value of ECMO 24 hours (p = 0.003), longer ECMO duration (p = 0.015), and surgical site bleeding (p = 0.025) were independent risk factors. CONCLUSION: ECMO was an effective technology to support the neonates with cardiopulmonary failure after open heart surgery. Control the lactate acidosis and surgical site bleeding event may be helpful for patients' recovery.

Risk factors of nosocomial infection after cardiac surgery in children with congenital heart disease.

BACKGROUND: The aim of our study was to analyze the risk factors of nosocomial infection after cardiac surgery in children with congenital heart disease (CHD). METHODS: We performed a retrospective cohort study, and children with CHD who underwent open-heart surgeries at Shanghai Children's Medical Center from January 1, 2012 to December 31, 2018 were included. The baseline characteristics of these patients of different ages, including neonates (0-1 months old), infants (1-12 months old) and children (1-10 years old), were analyzed, and the association of risk factors with postoperative nosocomial infection were assessed. RESULTS: A total of 11,651 subjects were included in the study. The overall nosocomial infection rate was 10.8%. Nosocomial infection rates in neonates, infants, and children with congenital heart disease were 32.9, 15.4, and 5.2%, respectively. Multivariate logistic regression analysis found age (OR 0798, 95%CI: 0.769-0.829; P < 0.001), STS risk grade (OR 1.267, 95%CI: 1.159-1.385; P < 0.001), body mass index (BMI) <5th percentile (OR 1.295, 95%CI: 1.023-1.639; P = 0.032), BMI >95th percentile (OR 0.792, 95%CI: 0.647-0.969; P = 0.023), cardiopulmonary bypass (CPB) time (OR 1.008, 95%CI: 1.003-1.012; P < 0.001) and aortic clamping time (OR 1.009, 1.002-1.015; P = 0.008) were significantly associated with nosocomial infection in CHD infants. After adjusted for confounding factors, we found STS risk grade (OR 1.38, 95%CI: 1.167-1.633; P < 0.001), BMI < 5th percentile (OR 1.934, 95%CI: 1.377-2.715; P < 0.001), CPB time (OR 1.018, 95%CI: 1.015-1.022; P < 0.001), lymphocyte/WBC ratiocut off value (OR 1.546, 95%CI: 1.119-2.136; P = 0.008) were significantly associated with nosocomial infection in CHD children. CONCLUSION: Our study suggested STS risk grade, BMI, CPB duration, low lymphocyte/WBC or high neutrophil/WBC ratio were independently associated with nosocomial infection in CHD infant and children after cardiac surgery.

Extracorporeal cardiopulmonary resuscitation in children after open heart surgery.

Extracorporeal membrane oxygenation (ECMO) provides cardiorespiratory support during cardiopulmonary resuscitation unresponsive to conventional methods. Here, we analyzed the extracorporeal cardiopulmonary resuscitation (ECPR) results of children in a cardiac arrest setting after cardiac surgery. Of 3119 cases of pediatric open-heart surgery, 31 required postoperative ECMO. Among the 31 patients, 11 experienced cardiac arrest and ECPR in the early postoperative period. These 11 patients' median age is 1.5 [range, 0.1-19] months and median weight is 3.9 [range, 2.9-10.3] kg. The medical records of ECPR cases were analyzed. The median ECMO-assisted time was 68 (range, 13-456) hours and 4 cases (36.4%) survived. The ECMO-assisted times were ≤2 days in 4 patients (all eventually died), ≥6 days in 3 patients (all also died), and all 4 cases supported for 2-6 days were discharged successfully (P = 0.006). In the survivors and nonsurvivors, peak lactate levels were 10.8 ± 7.04 and 22.8 ± 6.98 mmol/L (P = 0.023) and peak creatinine levels were 47.50 ± 25.9 and 153.7 ± 73.9 mg/dL (P = 0.035), respectively. In these 11 ECPR cases, the most common complications were bleeding requiring re-exploration (n = 6, 54.5%) and renal failure (n = 6, 54.5%). The incidence of renal failure was significantly correlated with hypoperfusion time (P = 0.015). ECPR is valuable in children with postoperative cardiac arrest. The higher peak lactate level, higher peak creatinine level, and prolonged ECMO duration were associated with higher mortality. Early diagnosis and intervention of residual anatomical problems could improve survival. Bleeding and renal failure were the most common complications and the incidence of renal failure may be correlated with longer hypoperfusion duration.

Effects of changes in the structural parameters of bionic straw sandwich concrete beetle elytron plates on their mechanical and thermal insulation properties.

To develop new, environmentally friendly prefabricated building materials, the effects of individual changes in structural parameters on the mechanical and thermal insulation properties of straw sandwich concrete beetle elytron plates (SCBEPs), i.e., sandwich plates with trabeculae constituting the core layer structure, were analyzed by ABAQUS. In addition, based on the analysis results, the structural parameters were preliminarily optimized. The results revealed the following. 1) The bearing capacity of a SCBEP is mainly controlled by deformation (i.e., the maximum deflection). The two most influencing factors on the deflection are the panel thickness T and the trabecular radius R. In contrast, although the panel area is very large, the influence of changing the panel thickness on the thermal insulation performance ranks only third. This demonstrates that the thermal bridge effect of the concrete trabeculae and edges is the primary limitation on further improvements to the thermal insulation performance of SCBEPs. 2) Based on the effects of individual changes in structural parameters on the performance of SCBEPs and their actual processing and application requirements, the structural parameters of a SCBEP with optimized mechanical properties and thermal insulation properties are determined. 3) Compared with aerated concrete wallboards, the optimized SCBEP has a higher rigidity, more compacted surface and better durability. Compared with straw concrete wallboards, the optimized SCBEP has a higher straw content and better thermal insulation performance. Thus, it provides a new avenue for the development of a new, lightweight wallboard.

Structural characteristics of the core layer and biomimetic model of the ladybug forewing.

To explore the characteristics of the core structure of ladybug (Harmonia axyridis) forewings, their microstructure was studied using microscopes. The results suggest that trabeculae exist in the frame of the beetle (ladybug) forewing for the first time; this study represents the first determination of the parameters N, the total number of trabeculae in each forewing, and λt, the ratio of the cross-sectional area of the trabeculae to the effective area of trabecular distribution. The cross-sectional area of a single trabecula in the ladybug forewing is smaller than those in two other kinds of beetles, Allomyrina dichotoma and Prosopocoilus inclinatus. However, the average trabecular density of the ladybug forewing is 84 per square millimeter, which is the highest among these three kinds of beetles. The λt values are 1.0%, 1.5% and 10.5% for H. axyridis, A. dichotoma and P. inclinatus, respectively, and the corresponding N values are approximately 1.4, 1.7 and 3.7 thousand, respectively. Based on these findings, a biomimetic model of the ladybug forewing is proposed, which is characterized by a core structure with a high-density distribution of thin trabeculae surrounded by a foam-like material.

Circulating histones for predicting prognosis after cardiac surgery: a prospective study.

OBJECTIVES: The objective of this study was to assess the perioperative changes in circulating histones and their relationships with other biomarkers and clinical outcomes after cardiac surgery with cardiopulmonary bypass (CPB) in patients. METHODS: Forty-eight patients with congenital cardiac diseases undergoing corrective procedure with CPB were prospectively enrolled in this study. Circulating histones, N-terminal pro-brain natriuretic peptide (NT-proBNP), procalcitonin (PCT) and C-reactive protein (CRP) were measured preoperatively (T0) and at 0 (T1), 24 (T2), 48 (T3) and 72 (T4) h postoperatively. The relationships between biomarkers and clinical outcomes were analysed. RESULTS: Circulating histones, NT-proBNP, PCT and CRP increased significantly postoperatively, with histones reaching the peak value earliest at T1. Circulating histone levels were higher in patients with adverse events. Receiver operating characteristic curve analysis showed that peak histone levels had a better predictive value for adverse events postoperatively. Peak histone levels correlated with the peak level of NT-proBNP (r = 0.563, P < 0.01), PCT (r = 0.551, P < 0.01), CRP (r = 0.606, P < 0.01) and clinical parameters such as ventilation time (r = 0.601, P < 0.01) and intensive care unit time (r = 0.623, P < 0.01). CONCLUSIONS: Circulating histones reached peak levels faster than NT-proBNP, PCT and CRP. Furthermore, peak histone levels correlated with biomarkers and postoperative clinical outcomes. Circulating histones may be used as a prognostic indicator for patients after cardiac surgery with CPB. CLINICAL TRIALS: ClinicalTrials.gov (ID: NCT02325765).

Rapid vascularization of tissue-engineered vascular grafts in vivo by endothelial cells in co-culture with smooth muscle cells.

A major challenge facing the development of tissue-engineered vascular grafts (TEVGs), promising living replacements for diseased vascular structures, is enhancing angiogenesis. To promote rapid vascularization, endothelial cells (ECs) were co-cultured with smooth muscle cells (SMCs) in decellularized small intestinal submucosa scaffolds to regenerate angiogenic-TEVGs (A-TEVGs). Observation of the A-TEVGs at 1 month post-implantation revealed that a rich network of neocapillaries lining the blood vessel wall had developed; that the ECs of the neovasculatures had been derived from previously seeded ECs and later invading ECs of the host's vascular bed; that tissue vascularization had not significantly impaired mechanical properties; and that the maximal tensile strength of the A-TEVGs was of the same order of magnitude as that of native porcine femoral arteries. These results indicate that of the co-culturing of ECs with SMCs could enhance vascularization of TEVGs in vivo, possibly increasing graft perfusion and host integration.

Three-dimensional bicontinuous ultrafast-charge and -discharge bulk battery electrodes.

Rapid charge and discharge rates have become an important feature of electrical energy storage devices, but cause dramatic reductions in the energy that can be stored or delivered by most rechargeable batteries (their energy capacity). Supercapacitors do not suffer from this problem, but are restricted to much lower stored energy per mass (energy density) than batteries. A storage technology that combines the rate performance of supercapacitors with the energy density of batteries would significantly advance portable and distributed power technology. Here, we demonstrate very large battery charge and discharge rates with minimal capacity loss by using cathodes made from a self-assembled three-dimensional bicontinuous nanoarchitecture consisting of an electrolytically active material sandwiched between rapid ion and electron transport pathways. Rates of up to 400C and 1,000C for lithium-ion and nickel-metal hydride chemistries, respectively, are achieved (where a 1C rate represents a one-hour complete charge or discharge), enabling fabrication of a lithium-ion battery that can be 90% charged in 2 minutes.

Template-assisted three-dimensional nanolithography via geometrically irreversible processing.

An innovative and versatile nanofabrication technique based on template assisted three-dimensional (3D) nanolithography is presented that takes advantage of the irreversibility of conformal growth and conformal etching at locations with negative surface curvatures in 3D templates. Using colloidal crystals as templates, nanoring particles are generated with quantity much higher than conventional methods. Relying on the same principle, metallodielectric photonic crystals with discrete metal elements are fabricated that show strong absorption in the near-IR and transmission at longer wavelengths.

Structural origin of the brown color of barbules in male peacock tail feathers.

We report detailed optical measurements and numerical simulations of brown barbules in male peacock tail feathers. Our results indicate that brown coloration is predominantly produced structurally by the two-dimensional (2D) photonic-crystal structure in the cortex layer of a barbule. The constructing strategies of brown coloration revealed by numerical simulations are indeed subtle, which are of great significance in the artificial constructions of mixed structural coloration. It is found that the structural configurations of the 2D photonic-crystal structure such as the lattice constant, the number of periods, and even the interdistance and missing holes between the two melanin layers nearest to the cortex surface, are important in the production of structural brown colors.

Coloration strategies in peacock feathers.

We report the mechanism of color production in peacock feathers. We find that the cortex in differently colored barbules, which contains a 2D photonic-crystal structure, is responsible for coloration. Simulations reveal that the photonic-crystal structure possesses a partial photonic bandgap along the direction normal to the cortex surface, for frequencies within which light is strongly reflected. Coloration strategies in peacock feathers are very ingenious and simple: controlling the lattice constant and the number of periods in the photonic-crystal structure. Varying the lattice constant produces diversified colors. The reduction of the number of periods brings additional colors, causing mixed coloration.