Targeting Inflammation and Oxidative Stress to Improve Outcomes in a TNBS Murine Crohn's Colitis Model

Inflammation and oxidative stress are implicated in the pathogenesis of Crohn's disease. Cerium oxide nanoparticle (CNP) conjugated to microRNA 146a (miR146a) (CNP-miR146a) is a novel compound with anti-inflammatory and antioxidative properties. We hypothesized that local administration of CNP-miR146a would improve colitis in a 2,4,6-Trinitrobenzenesulfonic acid (TNBS) mouse model for Crohn's disease by decreasing colonic inflammation. Balb/c mice were instilled with TNBS enemas to induce colitis. Two days later, the mice received cellulose gel enema, cellulose gel with CNP-miR146a enema, or no treatment. Control mice received initial enemas of 50% ethanol and PBS enemas on day two. The mice were monitored daily for weight loss and clinical disease activity. The mice were euthanized on days two or five to evaluate their miR146a expression, inflammation on histology, and colonic IL-6 and TNF gene expressions and protein concentrations. CNP-miR146a enema successfully increased colonic miR146a expression at 12 h following delivery. At the end of five days from TNBS instillation, the mice treated with CNP-miR146a demonstrated reduced weight loss, improved inflammation scores on histology, and reduced gene expressions and protein concentrations of IL-6 and TNF. The local delivery of CNP-miR146a in a TNBS mouse model of acute Crohn's colitis dramatically decreased inflammatory signaling, resulting in improved clinical disease.

Muscle Flap Technique Safe for On-ECMO Congenital Diaphragmatic Hernia Repair

INTRODUCTION

Prosthetic patches (patch) and muscle flaps (flap) are techniques used for repair of congenital diaphragmatic hernia (CDH) with a large defect unamenable to primary closure. We hypothesized that the flap technique for CDH repair while on extra-corporeal membrane oxygenation (on-ECMO) would have decreased bleeding complications compared to patch due to the hemostatic advantage of native tissue.

METHODS

A single-center retrospective comparative study of patients who underwent on-ECMO CDH repair between 2008 and 2022 was performed.

RESULTS

Fifty-two patients met inclusion criteria: 18 patch (34.6%) and 34 flap (65.4%). There was no difference in CDH severity between groups. On univariate analysis, reoperation for surgical bleeding was lower following flap repair compared to patch (23.5% vs 55.6%, respectively; p = 0.045), 48-h postoperative blood product transfusion was lower after flap repair (132 mL/kg vs 273.5 mL/kg patch; p = 0.006), and two-year survival was increased in the flap repair group compared to patch (53.1% vs 17.7%, respectively; p = 0.036). On multivariate analysis adjusting for CDH side, day on ECMO repaired, and day of life CDH repaired, flap repair was significantly associated with lower five-day postoperative packed red blood cell transfusion amount, improved survival to hospital discharge, and improved two-year survival.

CONCLUSIONS

Our experience suggests that the muscle flap technique for on-ECMO CDH repair is associated with reduced bleeding complications compared to prosthetic patch repair, which may in part be responsible for the improved survival seen in the flap repair group. These results support the flap repair technique as a favored method for on-ECMO CDH repair.

LEVEL OF EVIDENCE

Level III.

Dysregulation of miRNA-mRNA expression in fetal growth restriction in a caloric restricted mouse model

Fetal growth restriction (FGR) is associated with aberrant placentation and accounts for a significant proportion of perinatal deaths. microRNAs have been shown to be dysregulated in FGR. The purpose of this study was to determine microRNA-regulated molecular pathways altered using a caloric restricted mouse model of FGR. Pregnant mice were subjected to a 50% caloric restricted diet beginning at E9. At E18.5, RNA sequencing of placental tissue was performed to identify differences in gene expression between caloric restricted and control placentas. Significant differences in gene expression between caloric restricted and control placentas were observed in 228 of the 1546 (14.7%) microRNAs. Functional analysis of microRNA-mRNA interactions demonstrated enrichment of several biological pathways with oxidative stress, apoptosis, and autophagy pathways upregulated and angiogenesis and signal transduction pathways downregulated. Ingenuity pathway analysis also suggested that ID1 signaling, a pathway integral for trophoblast differentiation, is also dysregulated in caloric restricted placentas. Thus, a maternal caloric restriction mouse model of FGR results in aberrant microRNA-regulated molecular pathways associated with angiogenesis, oxidative stress, signal transduction, apoptosis, and cell differentiation. As several of these pathways are dysregulated in human FGR, our findings suggest that this model may provide an excellent means to study placental microRNA derangements seen in FGR.

Surgical Necrotizing Enterocolitis - Can We Predict the Need for Gastrostomy Tube Placement?

INTRODUCTION

Necrotizing enterocolitis (NEC) is a significant cause of morbidity and mortality among extremely premature infants. Approximately 50% of cases progress to surgery, frequently resulting in resection of necrotic bowel and ostomy creation. Premature neonates are at risk for bronchopulmonary dysplasia and feeding failure; surgery in these patients is higher risk. We evaluated the incidence of gastrostomy tube (GT) placement after ostomy reversal in surgical NEC to define a subset of patients who would benefit from concurrent ostomy reversal and GT placement.

METHODS

A single-center retrospective study of infants with surgical NEC requiring ostomy creation between 2007 and 2021 was performed.

RESULTS

Eighty patients met inclusion criteria. A GT was placed in 45/80 (56.3%), of which 3/45 (6.7%) were placed before, 20/45 (44.4%) concurrently with, and 22/45 (48.9%) after ostomy reversal. Between those who did and did not require GT placement, there were no significant differences in gestational age (27 versus 27 wk, P = 0.94) or birth weight (830 g versus 1055 g, P = 0.36). Hospital length of stay was longer in the GT group (128.2 versus 70.9 d, P < 0.0001). Time from ostomy reversal to hospital discharge was shorter when performed concurrently with GT (56 versus 77 d, P = 0.02). There were no differences in short-term or long-term GT related complications based on timing of GT placement.

CONCLUSIONS

GT placement occurred in approximately 50% of patients with surgical NEC and GT may be accomplished safely at the time of ostomy reversal thus reducing the need for an additional procedure.

In Utero Diagnosis of Spinal Dermal Sinus

INTRODUCTION

Congenital dermal sinus (CDS) is an open neural tube defect (NTD) that occurs in 1 in 2500 births a year and often goes undetected until patients present with complications like infection and neurological deficits. Early diagnosis and repair of CDS may prevent formation of these complications. In utero diagnosis of these lesions may improve long-term outcomes by enabling referral to specialty services and planned postnatal repair, however only two such cases have been reported in the literature. We present a third case of in utero diagnosis of CDS with a description and discussion of findings from surgical exploration and pathology.

CASE PRESENTATION

Routine prenatal ultrasound scan detected a tethered cystic structure arising from the back of the fetus at 20 weeks gestation. Dedicated fetal ultrasound confirmed the presence of a cystic lesion protruding through a lamina defect while fetal magnetic resonance imaging (MRI) showed an intact spinal cord and meninges, suggesting a diagnosis of CDS. Neurosurgery followed along closely and took the child for surgical exploration on day 2 of life. A fibrous stalk with an intradural component and associated cord tethering was excised. Histology showed fibrous tissue without an epithelial-lined lumen.

CONCLUSION

CDS is a form of NTD that occurs from nondisjunction of the cutaneous ectoderm and neuroectoderm during formation of the neural tube. Slight differences in how this error occurs can explain variations seen in this spectrum of disease, including CDS without an epithelial-lined lumen as seen in this case. Newborns with CDS can go undiagnosed for years and present with long-term complications. Fetal imaging can assist in early recognition and surgical excision of CDS in newborns.

Angiogenic and Inflammatory microRNA Regulation in a Mouse Model of Fetal Growth Restriction

INTRODUCTION

Fetal growth restriction (FGR) is associated with impaired angiogenesis and chronic inflammation. MicroRNAs (miRs) are short noncoding RNAs that regulate gene expression at the post-transcriptional level by targeting messenger RNA (mRNA) for degradation or by suppressing translation. We hypothesize that dysregulation of miR-15b, an antiangiogenic miR, and miR-146a, an anti-inflammatory miR, are associated with the FGR's pathogenesis.

METHODS

Pregnant mice were provided ad libitum access to food between E1 and E8. From E9-E18, dams received either a 50% caloric restricted diet (FGR) or continued ad libitum access (controls). Placentas were harvested at E18.5 and total RNA was extracted. Gene expression levels of miRs and mRNAs were compared between FGR and control placentas.

RESULTS

Placentas affected by FGR demonstrated increased expression of miR-15b. Vascular endothelial growth factor alpha, which is downregulated in response to increased levels of miR-15b, was suppressed. The anti-inflammatory miR, miR-146a, was downregulated, resulting in upregulation of proinflammatory (IL-6, IL-8, and NFkB1) and oxidative stress (HIF-1α, SOD2, and Nox2) mediators.

CONCLUSIONS

Aberrant angiogenesis and chronic inflammation seen in FGR appear to be associated with dysregulated miR-15b and miR-146a gene expression, respectively. This observation suggests these miRs play a post-transcriptional regulatory role in FGR, providing an insight into possible therapeutic targets.

Fetal lung volumes measured by MRI predict pulmonary morbidity among infants with giant omphaloceles

OBJECTIVE

Giant omphaloceles (GO) have associated pulmonary hypoplasia and respiratory complications. Total lung volumes (TLV) on fetal MRI can prognosticate congenital diaphragmatic hernia outcomes; however, its applicability to GO is unknown. We hypothesize that late gestation TLV and observed-to-expected TLV (O/E TLV) on fetal MRI correlate with postnatal pulmonary morbidity in GO.

METHOD

A single-institution retrospective review of GO evaluated between 2012 and 2022 was performed. Fetal MRI TLV between 32 and 36 weeks' gestation and O/E TLV throughout gestation were calculated and correlated with postnatal outcomes.

RESULTS

86 fetuses with omphaloceles were evaluated; however, only 26 met strict inclusion criteria. MRIs occurred between 18 and 36 weeks' gestation. Those requiring delivery room intubation had significantly lower late gestation TLV and O/E TLV. O/E TLV predicted tracheostomy placement and survival. Neither TLV nor O/E TLV predicted the length of hospitalization or supplemental oxygen after discharge. Three fetuses had a TLV less than 35 mL: one died of respiratory failure, and the other two required tracheostomy.

CONCLUSIONS

Fetal MRI TLV measured between 32 and 36 weeks' gestation and O/E TLV predict the need for delivery room intubation and tracheostomy. O/E TLV correlated with survival. These data support fetal MRI as a prognostic tool to predict GO associated pulmonary morbidity.

Triazolothiadiazine derivative positively modulates CXCR4 signaling and improves diabetic wound healing

Development of specific therapies that target and accelerate diabetic wound repair is an urgent need to alleviate pain and suffering and the huge socioeconomic burden of this debilitating disease. C-X-C Motif Chemokine Ligand 12 (CXCL12) also know an stromal cell-derived factor 1α (SDF-1α) is a chemokine that binds the CXC chemokine receptor type 4 (CXCR4) and activates downstream signaling resulting in recruitment of hematopoietic cells to locations of tissue injury and promotes tissue repair. In diabetes, low expression of CXCL12 correlates with impaired wound healing. Activation of CXCR4 receptor signaling with agonists or positive allosteric modulators (PAMs) provides a potential for small molecule therapeutic discovery and development. We recently reported high throughput screening and identification of the CXCR4 partial agonist UCUF-728, characterization of in vitro activity and reduced wound closure time in diabetic mice at 100 μM as a proof-of-concept study. We report here, the discovery of a second chemical scaffold demonstrating increased agonist potency and represented by thiadiazine derivative, UCUF-965. UCUF-965 is a potent partial agonist of β-arrestin recruitment in CXCR4 receptor overexpressing cell line. Furthermore, UCUF-965 potentiates the CXCL12 maximal response in cAMP signaling pathway, activates CXCL12 stimulated migration in lymphoblast cells and modulates the levels of specific microRNA involved in the complex wound repair process, specifically in mouse fibroblasts. Our results indicate that UCUF-965 acts as a PAM agonist of the CXCR4 receptor. Furthermore, UCUF-965 enhanced angiogenesis markers and reduced wound healing time by 36% at 10.0 μM in diabetic mice models compared to untreated control.

CNP-miR146a Decreases Inflammation in Murine Acute Infectious Lung Injury

Acute respiratory distress syndrome (ARDS) has approximately 40% in-hospital mortality, and treatment is limited to supportive care. Pneumonia is the underlying etiology in many cases with unrestrained inflammation central to the pathophysiology. We have previously shown that CNP-miR146a, a radical scavenging cerium oxide nanoparticle (CNP) conjugated to the anti-inflammatory microRNA(miR)-146a, reduces bleomycin- and endotoxin-induced acute lung injury (ALI) by decreasing inflammation. We therefore hypothesized that CNP-miR146a would decrease inflammation in murine infectious ALI. Mice were injured with intratracheal (IT) MRSA or saline followed by treatment with IT CNP-miR146a or saline control. Twenty-four hours post-infection, bronchoalveolar lavage fluid (BALF) and whole lungs were analyzed for various markers of inflammation. Compared to controls, MRSA infection significantly increased proinflammatory gene expression (IL-6, IL-8, TNFα, IL-1β; p < 0.05), BALF proinflammatory cytokines (IL-6, IL-8, TNFα, IL-1β; p < 0.01), and inflammatory cell infiltrate (p = 0.03). CNP-miR146a treatment significantly decreased proinflammatory gene expression (IL-6, IL-8, TNFα, IL-1β; p < 0.05), bronchoalveolar proinflammatory protein leak (IL-6, IL-8, TNFα; p < 0.05), and inflammatory infiltrate (p = 0.01). CNP-miR146a decreases inflammation and improves alveolar-capillary barrier integrity in the MRSA-infected lung and has significant promise as a potential therapeutic for ARDS.

CNP-miR146a improves outcomes in a two-hit acute- and ventilator-induced lung injury model

Acute respiratory distress syndrome (ARDS) has high mortality (~40 %) and requires the lifesaving intervention of mechanical ventilation. A variety of systemic inflammatory insults can progress to ARDS, and the inflamed and injured lung is susceptible to ventilator-induced lung injury (VILI). Strategies to mitigate the inflammatory response while restoring pulmonary function are limited, thus we sought to determine if treatment with CNP-miR146a, a conjugate of novel free radical scavenging cerium oxide nanoparticles (CNP) to the anti-inflammatory microRNA (miR)-146a, would protect murine lungs from acute lung injury (ALI) induced with intratracheal endotoxin and subsequent VILI. Lung injury severity and treatment efficacy were evaluated via lung mechanical function, relative gene expression of inflammatory biomarkers, and lung morphometry (stereology). CNP-miR146a reduced the severity of ALI and slowed the progression of VILI, evidenced by improvements in inflammatory biomarkers, atelectasis, gas volumes in the parenchymal airspaces, and the stiffness of the pulmonary system.

Third-trimester percentage predicted lung volume and percentage liver herniation as prognostic indicators in congenital diaphragmatic hernia

BACKGROUND

Over the last two decades, fetal imaging has greatly improved, and new prenatal imaging measurements have been developed to characterize congenital diaphragmatic hernia (CDH) severity.

OBJECTIVE

To determine the best prenatal imaging predictor of postnatal CDH outcomes, including use of extracorporeal membrane oxygenation (ECMO) and in-hospital mortality, with particular attention to the percentage of liver herniation (%LH) as a predictor. Additionally, we sought to guide best practices across hospital systems including improved models of prenatal risk assessment.

MATERIALS AND METHODS

We conducted a retrospective review of infants with left CDH who were prenatally diagnosed. We analyzed prenatal imaging measurements including observed-to-expected (O/E) lung-to-head ratio (LHR) on US, percentage predicted lung volume (PPLV) on MRI, and O/E total fetal lung volume (TFLV) and %LH on MRI. We compared prenatal imaging characteristics for infants with (1) in-hospital postnatal mortality and (2) use of ECMO. Then we performed multivariate logistic regression to determine independent predictors of postnatal outcomes.

RESULTS

We included 63 infants with a median gestation of 34 weeks at the time of prenatal MRI. Low O/E LHR (31.2 vs. 50, P < 0.0001), PPLV (14.7 vs. 22.6, P < 0.0001) and O/E TLFV (24.6 vs. 38.3, P < 0.0001) and high %LH (15.1 vs. 2.1, P = 0.0006) were associated with worse postnatal outcomes; however, only PPLV was predictive of survival and need for ECMO on multivariable analysis. PPLV survival to discharge model showed an area under the curve (AUC) of 0.93 (95% confidence interval [CI]: 0.86, 0.99), P < 0.0001; and an odds ratio of 68.7 (95% CI: 6.5-2,302), P = 0.003. PPLV need for ECMO model showed AUC = 0.87 (95% CI: 0.78, 0.96), P < 0.0001; and odds ratio = 20.1 (95% CI: 3.1-226.3), P = 0.011.

CONCLUSION

Low O/E LHR, PPLV and O/E TFLV and high %LH in the third trimester are associated with worse postnatal outcomes. PPLV most strongly predicted outcome using a logistic regression model. Percentage of liver herniation was not an independent predictor of outcomes.

Early outcomes of a myofascial repair technique for fetal myelomeningocele

PURPOSE

Fetal repair of myelomeningocele (MMC) and myeloschisis leads to improved neurologic outcomes compared to postnatal repair, but the effects of modifications in closure techniques have not been extensively studied. Previous work has suggested that a watertight repair is requisite for improvement in hindbrain herniation (HBH) and to decrease postnatal hydrocephalus (HCP). Our institution adopted the myofascial closure technique for open fetal MMC repair in July 2019, which we hypothesized would result in decreased need for patch closure, improved HBH, and decreased rate of surgically-treated HCP.

METHODS

A single-center retrospective study of patients who underwent fetal MMC or myeloschisis repair between March 2013 and February 2022 was performed. Outcomes were evaluated (n = 70 prior to July 2019, n = 34 after July 2019). Statistical significance was determined by Fisher's exact and Chi square tests (p < 0.05 significant).

RESULTS

Patients who underwent myofascial closure were less likely to require a patch for skin closure (14.7% vs 58.6%, p < 0.0001). Myofascial closure was also associated with an increased rate of HBH improvement on two-week postoperative fetal MRI (93.9% vs 65.7%, p = 0.002). Surgically-treated HCP at one year was lower in the myofascial closure group (n = 21), however this did not reach statistical significance (23.8% vs 41.9%, p = 0.19).

CONCLUSIONS

We conclude that the myofascial closure technique for repair of fetal MMC and myeloschisis is associated with significantly decreased need for patch closure and improvement in hindbrain herniation compared to our previous skin closure technique. These results support a surgical approach that employs a multilayer watertight closure.

Effects of microRNAs on angiogenesis in diabetic wounds

Diabetes mellitus is a morbid condition affecting a growing number of the world population, and approximately one third of diabetic patients are afflicted with diabetic foot ulcers (DFU), which are chronic non-healing wounds that frequently progress to require amputation. The treatments currently used for DFU focus on reducing pressure on the wound, staving off infection, and maintaining a moist environment, but the impaired wound healing that occurs in diabetes is a constant obstacle that must be faced. Aberrant angiogenesis is a major contributor to poor wound healing in diabetes and surgical intervention is often necessary to establish peripheral blood flow necessary for healing wounds. Over recent years, microRNAs (miRNAs) have been implicated in the dysregulation of angiogenesis in multiple pathologies including diabetes. This review explores the pathways of angiogenesis that become dysregulated in diabetes, focusing on miRNAs that have been identified and the mechanisms by which they affect angiogenesis.

Immunomodulatory biomaterials on chemokine signaling in wound healing

Normal wound healing occurs through a careful orchestration of cytokine and chemokine signaling in response to injury. Chemokines are a small family of chemotactic cytokines that are secreted by immune cells in response to injury and are primarily responsible for recruiting appropriate immune cell types to injured tissue at the appropriate time. Dysregulation of chemokine signaling is suspected to contribute to delayed wound healing and chronic wounds in diseased states. Various biomaterials are being used in the development of new therapeutics for wound healing and our understanding of their effects on chemokine signaling is limited. It has been shown that modifications to the physiochemical properties of biomaterials can affect the body's immune reaction. Studying these effects on chemokine expression by various tissues and cell type can help us develop novel biomaterial therapies. In this review, we summarize the current research available on both natural and synthetic biomaterials and their effects on chemokine signaling in wound healing. In our investigation, we conclude that our knowledge of chemokines is still limited and that many in fact share both pro-inflammatory and anti-inflammatory properties. The predominance of either a pro-inflammatory or anti-inflammatory profile is mostly likely dependent on timing after injury and exposure to the biomaterial. More research is needed to better understand the interaction and contribution of biomaterials to chemokine activity in wound healing and their immunomodulatory effects.

Assessing the bio-stability of microRNA-146a conjugated nanoparticles via electroanalysis

The number of diabetics is increasing worldwide and is associated with significant instances of clinical morbidity. Increased amounts of reactive oxygen species (ROS) and proinflammatory cytokines are associated with the pathogenesis of diabetic wounds and result in a significant delay in healing. Our previous studies have shown the ability of a cerium oxide nanoparticle (CNP) formulation conjugated with the anti-inflammatory microRNA miR146a (CNP-miR146a) to enhance the healing of diabetic wounds. The observed therapeutic activity exceeded the combined efficacies of the individual conjugate components (CNPs and miR146a alone), suggesting a synergistic effect. The current study evaluates whether the previously observed enhanced activity arises from increased agent delivery (simple nanocarrier activity) or is specific to the CNP-miR146a formulation (functional, bio-active nanomaterial). Comparison with miR146a conjugated gold (bioactive, metal) and silica (bioinert, oxide) nanoparticles (AuNPs and SiO₂NPs) was performed in the presence of H₂O₂, as an analogue to the high levels of ROS present in the diabetic wound environment. Electrochemical studies, materials characterization, and chemical assays showed limited interaction of AuNP-miR146a with H₂O₂ and instability of SiO₂NP-miR146a over time. In contrast, and in support of our prior results, CNP-miR146a displayed chemical stability and persistent ROS scavenging ability. Furthermore, it was determined that CNPs protect miR146a from oxidative damage under prolonged exposure to H₂O₂, whereas AuNPs and SiO₂NPs were shown to be ineffective. Overall, these results reinforce the ability of CNPs to stabilize and protect miRNA while exhibiting robust antioxidant properties, suggesting that therapeutic activity observed in related earlier studies is not limited to a facile nanocarrier function.

Engineered Faceted Cerium Oxide Nanoparticles for Therapeutic miRNA Delivery

In general, wound healing is a highly ordered process, with distinct phases of inflammation, proliferation, and remodeling. However, among diabetic patients, the progression through these phases is often impeded by increased level of oxidative stress and persistent inflammation. Our previous studies demonstrated that cerium oxide nanoparticles (CNPs) conjugated with therapeutic microRNA146a (miR146a) could effectively enhance wound healing by targeting the NFκB pathway, reducing oxidative stress and inflammation. In the present study, we consider the potential effects of nanomaterial surface-faceting and morphology on the efficacy of miRNA delivery. Compared with octahedral-CNPs and cubic-CNPs, rod-CNPs exhibited higher loading capacity. In addition, in comparing the influence of particle morphology on wound healing efficacy, several markers for bioactivity were evaluated and ascribed to the combined effects of the gene delivery and reactive oxygen species (ROS) scavenging properties. In the cellular treatment study, rod-CNP-miR146a displayed the greatest miR146a delivery into cells. However, the reduction of IL-6 was only observed in the octahedral-CNP-miR146a, suggesting that the efficacy of the miRNA delivery is a result of the combination of various factors. Overall, our results give enlightenments into the relative delivery efficiency of the CNPs with different morphology enhancing miRNA delivery efficacy.

Discovery of Small Molecule Activators of Chemokine Receptor CXCR4 That Improve Diabetic Wound Healing

Diabetes produces a chronic inflammatory state that contributes to the development of vascular disease and impaired wound healing. Despite the known individual and societal impacts of diabetic ulcers, there are limited therapies effective at improving healing. Stromal cell-derived factor 1α (SDF-1α) is a CXC chemokine that functions via activation of the CXC chemokine receptor type 4 (CXCR4) receptor to recruit hematopoietic cells to locations of tissue injury and promote tissue repair. The expression of SDF-1α is reduced in diabetic wounds, suggesting a potential contribution to wound healing impairment and presenting the CXCR4 receptor as a target for therapeutic investigations. We developed a high-throughput β-arrestin recruitment assay and conducted structure-activity relationship (SAR) studies to screen compounds for utility as CXCR4 agonists. We identified CXCR4 agonist UCUF-728 from our studies and further validated its activity in vitro in diabetic fibroblasts. UCUF-728 reduced overexpression of miRNA-15b and miRNA-29a, negative regulators of angiogenesis and type I collagen production, respectively, in diabetic fibroblasts. In vivo, UCUF-728 reduced the wound closure time by 36% and increased the evidence of angiogenesis in diabetic mice. Together, this work demonstrates the clinical potential of small molecule CXCR4 agonists as novel therapies for pathologic wound healing in diabetes.

Photopolymerized Zwitterionic Hydrogels with a Sustained Delivery of Cerium Oxide Nanoparticle-miR146a Conjugate Accelerate Diabetic Wound Healing

In the United States, $87 billion per year is spent on the care of diabetic ulcers alone. Although the pathophysiology of diabetic wound healing is multifaceted, high systemic levels of inflammation and increased reactive oxygen species are often implicated in the wound healing impairment. Zwitterionic materials have been demonstrated to reduce inflammation and increase extracellular matrix deposition in wound beds, and here, we demonstrate a fabrication method for photopolymerized zwitterionic hydrogels that also enables sustained drug delivery over time. A therapeutic molecule of interest that is examined in this work is cerium oxide nanoparticle tagged with microRNA-146a (CNP-miR146a) to combat both oxidative stress and inflammation. The hydrogels are composed of zwitterionic and nonzwitterionic monomers, and the hydrogel formation occurs in the absence of a crosslinker. The hydrogels exhibit a wide range of stiffness and mechanical properties depending on their monomer content. Additionally, these hydrogels exhibit sustained release of nanoparticles and proteins. Finally, when employed in an in vivo diabetic mouse wound healing model, the zwitterionic hydrogels alone and laden with the CNP-miR146a conjugate significantly improved the rate of diabetic wound healing. Overall, these materials have excellent potential to be used as a topical treatment for chronic diabetic wounds.

Cerium oxide nanoparticle conjugation to microRNA-146a mechanism of correction for impaired diabetic wound healing

Diabetic wounds represent a significant healthcare burden and are characterized by impaired wound healing due to increased oxidative stress and persistent inflammation. We have shown that CNP-miR146a synthesized by the conjugation of cerium oxide nanoparticles (CNP) to microRNA (miR)-146a improves diabetic wound healing. CNP are divalent metal oxides that act as free radical scavenger, while miR146a inhibits the pro-inflammatory NFκB pathway, so CNP-miR146a has a synergistic role in modulating both oxidative stress and inflammation. In this study, we define the mechanism(s) by which CNP-miR146a improves diabetic wound healing by examining immunohistochemical and gene expression analysis of markers of inflammation, oxidative stress, fibrosis, and angiogenesis. We have found that intradermal injection of CNP-miR146a increases wound collagen, enhances angiogenesis, and lowers inflammation and oxidative stress, ultimately promoting faster closure of diabetic wounds.

Topical gel-based biomaterials for the treatment of diabetic foot ulcers

Diabetic foot ulcers (DFUs) are a devastating ailment for many diabetic patients with increasing prevalence and morbidity. The complex pathophysiology of DFU wound environments has made finding effective treatments difficult. Standard wound care treatments have limited efficacy in healing these types of chronic wounds. Topical biomaterial gels have been developed to implement novel treatment approaches to improve therapeutic effects and are advantageous due to their ease of application, tunability, and ability to improve therapeutic release characteristics. Here, we provide an updated, comprehensive review of novel topical biomaterial gels developed for treating chronic DFUs. This review will examine preclinical data for topical gel treatments in diabetic animal models and clinical applications, focusing on gels with protein/peptides, drug, cellular, herbal/antioxidant, and nano/microparticle approaches. STATEMENT OF SIGNIFICANCE: By 2050, 1 in 3 Americans will develop diabetes, and up to 34% of diabetic patients will develop a diabetic foot ulcer (DFU) in their lifetime. Current treatments for DFUs include debridement, infection control, maintaining a moist wound environment, and pressure offloading. Despite these interventions, a large number of DFUs fail to heal and are associated with a cost that exceeds $31 billion annually. Topical biomaterials have been developed to help target specific impairments associated with DFU with the goal to improve healing. A summary of these approaches is needed to help better understand the current state of the research. This review summarizes recent research and advances in topical biomaterials treatments for DFUs.

Reduction in blood product transfusion requirements with early on-ECMO repair of congenital diaphragmatic hernia

Background

For infants with severe congenital diaphragmatic hernia (CDH) stabilized with extracorporeal membrane oxygenation (ECMO), early repair on ECMO improves outcome; however when compared to operative repair after ECMO, repair on ECMO is associated with increase bleeding risk and need for blood product transfusions.

Methods

A retrospective review of 54 patients with CDH placed on ECMO prior to CDH repair was performed. For the subset of patients repaired on ECMO, analysis comparing those repaired early (within 48 h of cannulation) and late (beyond 48 h) on ECMO was performed. Outcomes of interest included survival to discharge, days on ECMO, and postoperative blood product utilization.

Results

When compared to those patients repaired prior to 48 h of ECMO initiation, 57.7% of patients survived versus 40.9% of late repair patients. For those repaired early, blood product utilization was significantly less. Early repair patients received a median of 72 mL/kg packed red blood cells (PRBC) and 75 mL/kg platelets compared to 151.9 mL/kg and 98.7 mL/kg, respectively (p < 0.05 respectively). There was no difference in median days on ECMO (p = 0.38).

Conclusion

Our data supports prior reports of improved outcome with repair with 48 h of ECMO initiation and suggests early repair on ECMO is associated with less bleeding and decreased blood product requirement in the postoperative period.

The novel fetal MRI O/E CLV versus O/E LHR in predicting prognosis in congenital diaphragmatic hernias: can we teach an old dog new tricks?

PURPOSE

In congenital diaphragmatic hernia (CDH), ultrasound (U/S) measurements of the contralateral lung commonly provide the observed-to-expected lung-to-head ratio (O/E LHR) and are used to determine the severity of pulmonary hypoplasia. Fetal magnetic resonance imaging (MRI) measurement of the observed-to-expected total lung volume (O/E TLV) has been used as an adjunct to O/E LHR in predicting outcomes. Since O/E LHR only measures the contralateral lung, we sought to investigate if MRI measurements of the contralateral lung volume (O/E CLV) can accurately predict outcomes in CDH. We hypothesize that O/E CLV is a better predictor of CDH outcomes than O/E LHR.

METHODS

We identified all infants with a prenatal diagnosis of CDH at our fetal center who had both MRI and U/S measurements. Using lung volume ratios of right-left 55:45, we calculated O/E CLV from O/E TLV. We used receiver-operating characteristic (ROC) curves to calculate the area under the curve (AUC) to compare the predictive accuracy of O/E CLV to O/E LHR for ECMO support, as well as survival to both discharge and 1 year.

RESULTS

Seventy-four patients had complete prenatal imaging with 39% requiring ECMO support. The median O/E CLV was 48.0% and the median O/E LHR was 42.3%. O/E CLV was a better predictor of the need for ECMO support (AUC 0.81 vs. 0.74). O/E CLV was a better predictor of survival to discharge (AUC 0.84 vs. 0.64) and 1-year survival (AUC 0.83 vs. 0.63) than O/E LHR.

CONCLUSION

O/E LHR is a well-validated standard for predicting outcomes and guiding prenatal counseling in CDH. We provide evidence that fetal MRI measurements of the contralateral lung volume corrected for gestational age were more accurate in predicting the need for ECMO and survival. Future prospective studies validating O/E CLV regarding outcomes and ECMO utilization are warranted.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Macrophage polarization and diabetic wound healing

Diabetes mellitus is a costly disease and nearly one-third of these costs are attributed to management of diabetic foot disease including chronic, non-healing, diabetic foot ulcers. Therefore, much effort has been placed into understanding the pathogenesis of diabetic wounds and novel therapeutics. A relatively new area of interest has been macrophage polarization and its role in diabetic wound healing. Diabetic wounds show dysregulated and persistent M1 (pro-inflammatory) macrophage polarization whereas normal wounds will display a transition to M2 (pro-healing) macrophages around day three after wounding. We reviewed factors known to affect macrophage polarization, mostly focused on those that contribute to M2 macrophage polarization, and potential treatments that at least in part target macrophage polarization in the diabetic wound bed. Much of the work has been aimed at reducing hyperglycemia and encouraging pro-inflammatory cytokine neutralization or decreased expression given this has a significant role in producing M1 macrophages. Treatment of diabetic wounds will likely require a multi-modal approach including management of underlying diabetes and control of hyperglycemia, topical therapeutics, and prevention of secondary infection and inflammation.

Nanoparticle mediated RNA delivery for wound healing

Wound healing is a complicated physiological process that comprises various steps, including hemostasis, inflammation, proliferation, and remodeling. The wound healing process is significantly affected by coexisting disease states such as diabetes, immunosuppression, or vascular disease. It can also be impacted by age, repeated injury, or hypertrophic scarring. These comorbidities can affect the rate of wound closure, the quality of wound closure, and tissues' function at the affected sites. There are limited options to improve the rate or quality of wound healing, creating a significant unmet need. Advances in nucleic acid research and the human genome project have developed potential novel approaches to address these outstanding requirements. In particular, the use of microRNA, short hairpin RNA, and silencing RNA is unique in their abilities as key regulators within the physiologic machinery of the cell. Although this innovative therapeutic approach using ribonucleic acid (RNA) is an attractive approach, the application as a therapeutic remains a challenge due to site-specific delivery, off-target effects, and RNA degradation obstacles. An ideal delivery system is essential for successful gene delivery. An ideal delivery system should result in high bioactivity, inhibit rapid dilution, controlled release, allow specific activation timings facilitating physiological stability, and minimize multiple dosages. Currently, these goals can be achieved by inorganic nanoparticle (NP) (e.g., cerium oxide, gold, silica, etc.) based delivery systems. This review focuses on providing insight into the preeminent research carried out on various RNAs and their delivery through NPs for effective wound healing. This article is categorized under: Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Therapeutic Approaches and Drug Discovery > Emerging Technologies Biology-Inspired Nanomaterials > Nucleic Acid-Based Structures.

Evaluation of skin care concerns and patient's perception of the effect of NanoSilk Cream on facial skin

BACKGROUND

Skin aging is an inevitable process with one of the key features of aging being dryness or flakiness of the skin. Previous in vivo and in vitro testing has highlighted that a silk-based product may be effective in improving moisture retention in skin.

METHODS

We evaluated the safety and efficacy of our silk-based product through a combination of objective- including scanning electron microscopy (SEM) and EpiDerm Skin Irritation tests - and subjective tests - including direct evaluation of patient's own perception of their skin.

RESULTS

In alignment with previous studies, patients reported significant concerns about aging, wrinkling, or saggy skin. We found that our silk-based product was safe and effective in improving hydration and resilience of facial skin and a majority of participants stated they would continue to use this product, when commercially available.

CONCLUSION

Our novel silk-based product, NanoSilk Cosmo, is safe for use on human facial skin and it improves skin resiliency and hydration.

A Large Mammalian Model of Myocardial Regeneration After Myocardial Infarction in Fetal Sheep

Objective: Ischemic heart disease accounts for over 20% of all deaths worldwide. As the global population faces a rising burden of chronic diseases, such as hypertension, hyperlipidemia, and diabetes, the prevalence of heart failure due to ischemic heart disease is estimated to increase. We sought to develop a model that may more accurately identify therapeutic targets to mitigate the development of heart failure following myocardial infarction (MI). Approach: Having utilized fetal large mammalian models of scarless wound healing, we proposed a fetal ovine model of myocardial regeneration after MI. Results: Use of this model has identified critical pathways in the mammalian response to MI, which are differentially activated in the regenerative, fetal mammalian response to MI when compared to the reparative, scar-forming, adult mammalian response to MI. Innovation: While the foundation of myocardial regeneration research has been built on zebrafish and rodent models, effective therapies derived from these disease models have been lacking; therefore, we sought to develop a more representative ovine model of myocardial regeneration after MI to improve the identification of therapeutic targets designed to mitigate the development of heart failure following MI. Conclusions: To develop therapies aimed at mitigating this rising burden of disease, it is critical that the animal models we utilize closely reflect the physiology and pathology we observe in human disease. We encourage use of this ovine large mammalian model to facilitate identification of therapies designed to mitigate the growing burden of heart failure.

Deviations in MicroRNA-21 Expression Patterns Identify a Therapeutic Target for Diabetic Wound Healing

Chronic inflammation plays a major role in impaired healing of diabetic wounds. Mounting evidence highlights the role of controlled, sequential polarization of macrophages in producing the appropriate progression through the stages of wound healing: inflammation (pro- inflammatory stage), proliferation and remodeling (regenerative stage). Non-coding RNAs, including microRNAs, maintain critical roles in regulating normal biological processes, such as wound healing; and are being explored as therapeutic targets for modulating dysfunction in disease states. Interestingly, microRNA-21 (miR-21) has a suggested role in the induction of pro-inflammatory and regenerative stages of healing, but clarity remains elusive on the specific mechanisms determining the direction miR-21 shifts wound healing processes. Findings by Liechty et al. in International Journal of Molecular Science indicate an important role of miR-21, in shaping the wound healing cascade by preferentially inducing M1-like (pro-inflammatory) polarization of macrophages in the early phase of diabetic wound healing. Persistent elevation of miR-21 is suggestive of sustained pro-inflammatory drive, and subsequent wound healing impairment, in the skin of diabetic murine models and diabetic human skin. Differences in the expression patterns of miR-21 during diabetic wound healing identifies the potentially critical role of therapeutic timing, for miR-21 based therapies, in driving positive outcomes for patients.

Continuous local bupivacaine wound infusion reduces oral opioid use for acute postoperative pain control following myelomeningocele repair

BACKGROUND

For pregnancies complicated by fetal myelomeningocele who meet the established criteria, prenatal closure is a viable management option. Prenatal closure is an open procedure, with some techniques requiring greater dissection of maternal tissue than cesarean delivery; pain control is an important postoperative goal. Given the rising rates of opioid dependence and concerns regarding the fetal and neonatal effects of opioid use, our practice has turned to nonopioid pain management techniques.

OBJECTIVE

This study aimed to compare postoperative opioid use and pain scores in women undergoing open fetal myelomeningocele repair with and without continuous local bupivacaine wound infusion.

STUDY DESIGN

This was a retrospective, single-center chart review of all consecutive patients who underwent open myelomeningocele repair from March 2013 to December 2019. Women were enrolled at the time of referral and locally followed for 2 weeks postoperatively. The control group received patient-controlled epidural analgesia for 48 hours with acetaminophen and oral and intravenous opioids as needed. The treatment group received patient-controlled epidural analgesia for 24 hours with acetaminophen, oral and intravenous opioids, and continuous local bupivacaine infusion. Pain scores, medication use, and postoperative milestones and complications through discharge were abstracted from the chart and compared.

RESULTS

Of 72 subjects, 51 were in the control group and 21 in the treatment group. Total opioid use, including intravenous doses (165 vs 52.5 mg; P=.001) and daily average oral opioid use (30 vs 10.5 mg; P=.002) were lower in the treatment group. In addition, 24% of women in the treatment group used no opioid postoperatively, compared with 4% in the control group. There was no difference in postoperative day 1 to 4 pain scores, antiemetic use, or bowel function; the treatment group was discharged significantly earlier.

CONCLUSION

Postoperative opioid use was reduced in women who received continuous local wound infusion of bupivacaine for incisional pain control after prenatal myelomeningocele repair. Pain control is paramount following open myelomeningocele repair; local bupivacaine wound infusion is an important adjunct to reduce opioid use postoperatively.

Congenital diaphragmatic hernias: Severe defect grade predicts the need for fundoplication

Over one-third of infants with congenital diaphragmatic hernia (CDH) eventually require a Nissen fundoplication (NF). We examined pre- and intraoperative predictors for need of a NF in children undergoing CDH repair to elucidate, which patients will need a later NF.A retrospective analysis of all consecutive patients undergoing CDH repair at our institution from 2008 to 2018 was performed. Patients who underwent a NF were compared to those who did not (noNissen). Logistic regression analysis was performed to find independent predictors for NF in patients undergoing CDH repair. Severe Defect Grade was defined as defect >50% of the hemidiaphragm and intrathoracic liver.One hundred twenty-six patients were included, 42 (33%) underwent NF at a median of 61 days after CDH repair. Intrathoracic liver was more frequent in the NF (71%) versus noNissen (45%) group (P = .008). Absence of >50% of the hemidiaphragm was more frequent in the NF group (76% vs 31%, P < .001). Severe Defect Grade emerged as independent predictor for NF (odds ratio 7, 95% confidence interval 3-16, P < .001).Severe Defect Grade emerged as independent predictor for NF after CDH repair.

Nanosilk Increases the Strength of Diabetic Skin and Delivers CNP-miR146a to Improve Wound Healing

Diabetes mellitus is a metabolic disorder associated with properties and an increased risk of chronic wounds due to sustained pro-inflammatory response. We have previously of radical scavenging cerium oxide nanoparticles (CNP) conjugated to the anti-inflammatory microRNA (miR)-146a, termed CNP-miR146a, improves diabetic wound healing by synergistically lowering oxidative stress and inflammation, and we sought to evaluate this treatment in a topical application. Silk fibroin is a biocompatible polymer that can be fabricated into nanostructures, termed nanosilk. Nanosilk is characterized by a high strength-to-density ratio and an ability to exhibit strain hardening. We therefore hypothesized that nanosilk would strengthen the biomechanical properties of diabetic skin and that nanosilk solution could effectively deliver CNP-miR146a to improve diabetic wound healing. The ability of nanosilk to deliver CNP-miR146a to murine diabetic wounds and improve healing was assessed by the rate of wound closure and inflammatory gene expression, as well as histologic analysis. The effect of nanosilk on the properties of human diabetic skin was evaluated by testing the biomechanical properties following topical application of a 7% nanosilk solution. Diabetic murine wounds treated with topical nanosilk and CNP-miR146a healed by day 14.5 compared to day 16.8 in controls (p = 0.0321). Wounds treated with CNP-miR146a had higher collagen levels than controls (p = 0.0126) with higher pro-fibrotic gene expression of TGFβ-1 (p = 0.0092), Col3α1 (p = 0.0369), and Col1α2 (p = 0.0454). Treatment with CNP-miR146a lowered pro-inflammatory gene expression of IL-6 (p = 0.0488) and IL-8 (p = 0.0009). Treatment of human diabetic skin with 7% nanosilk solution resulted in significant improvement in maximum load and modulus (p < 0.05). Nanosilk solution is able to strengthen the biomechanical properties of diabetic skin and can successfully deliver CNP-miR146a to improve diabetic wound healing through inhibition of pro-inflammatory gene signaling and promotion of pro-fibrotic processes.

Thromboelastography-guided management of coagulopathy in neonates with congenital diaphragmatic hernia supported by extracorporeal membrane oxygenation

PURPOSE

Congenital diaphragmatic hernia (CDH) can cause severe hemodynamic deterioration requiring support with extracorporeal membrane oxygenation (ECMO). ECMO is associated with hemorrhagic and thromboembolic complications. In 2015, we standardized anti-coagulation management on ECMO, incorporating thromboelastography (TEG) as an adjunct to manage hemostasis of CDH patients. The purpose of this study is to evaluate our blood product utilization, choice of blood product use in response to abnormal TEG parameters, and the associated effect on bleeding and thrombotic complications.

METHODS

We retrospectively reviewed all CDH neonates supported by ECMO between 2008 and 2018. Blood product administration, TEG data, and hemorrhagic and thrombotic complications data were collected. We divided subjects into two groups pre-2015 and post-2015.

RESULTS

After 2015, platelet transfusion was administered for a low maximum amplitude (MA) more frequently (77% compared to 65%, p = 0.0007). Cryoprecipitate was administered less frequently for a low alpha-angle (28% compared to 41%, p = 0.0016). There was no difference in fresh frozen plasma use over time. After standardizing the use of TEG, we observed a significant reduction in hemothoraces (18% compared to 54%, p = 0.026).

CONCLUSION

Institutional standardization of anti-coagulation management of CDH neonates on ECMO, including the use of goal-directed TEG monitoring may lead to improved blood product utilization and a decrease in bleeding complications in neonates with CDH supported by ECMO.

LEVEL OF EVIDENCE/TYPE OF STUDY

Level III, Retrospective comparative study.

Determining maternal risk factors for gastroschisis using colorado's birth registry database

AIM OF STUDY

Gastroschisis is a congenital abdominal wall defect which results in herniation of abdominal contents. The objective of this study was to determine the maternal risk factors for gastroschisis in Colorado.

METHODS

A case-control study was performed using the Birth Registry database from 2007 to 2016. The outcome was gastroschisis, and the main variable was maternal age which was divided into <21, 21-30, and >30 years of age. Descriptive analysis, bivariate analysis, and logistic regression was performed.

RESULTS

There were 236 cases of gastroschisis compared to 944 controls. Maternal age did vary significantly between groups (23.4 ± 5 years (cases) vs. 28.7 ± 5.9 years (controls); p < 0.0001). Unadjusted analysis demonstrated that those with young maternal age (<21 years of age) had a 14.14 (95% CI 8.44-23.67) higher odds of gastroschisis compared to those >30 years of age. Independent risk factors for gastroschisis were exposure to prenatal and first trimester cigarettes, prenatal and first trimester alcohol, and chlamydia infection. The odds (4.41, 95% CI 1.36-14.26) of gastroschisis were highest in those with first trimester cigarette exposure and young maternal age (p = 0.03).

CONCLUSIONS

Young maternal age, cigarette exposure, alcohol exposure, and chlamydia infection increase the odds of gastroschisis. The interaction between young maternal age and first trimester cigarette exposure significantly increases the odds of gastroschisis.

TYPE OF STUDY

Prognosis Study.

LEVEL OF EVIDENCE

Level III.

Silk fibroin nanofibrous mats for visible sensing of oxidative stress in cutaneous wounds

Amplex red infused silk mats in visible detection of oxidative stress in the cutaneous wound over time.

A congenital cystic pulmonary airway malformation occurring together with both an extralobar pulmonary sequestration and an esophageal duplication cyst

A foregut duplication cyst occurring together with both a congenital cystic pulmonary airway malformation and extralobar pulmonary sequestration is an unusual combination. Prenatal ultrasound, MRI, and postnatal CT are helpful for operative planning. Surgical resection is the definitive management for all three anomalies.

Low postnatal CRI values are associated with the need for ECMO in newborns with CDH

INTRODUCTION

Accurate, real-time technology is needed to predict which newborns with congenital diaphragmatic hernia (CDH) will require ECMO. The Compensatory Reserve Index (CRI) is a noninvasive monitoring technology that continuously trends an individual's capacity to compensate from normovolemia (CRI = 1) to decompensation (CRI = 0). We hypothesized that postnatal CRI values would be lower in CDH newborns that required ECMO than those who did not require ECMO.

METHODS

Newborns with a CDH were prospectively monitored with a CipherOx® CRI M1 device. We compared CRI values from delivery to ECMO (ECMO group) versus delivery to clinical stabilization (non-ECMO group).

RESULTS

Postnatal CRI values were available from 26 newborns. Eight underwent ECMO within 33 h of delivery, and median CRI prior to ECMO was 0.068 (IQR: 0.057, 0.078). Eighteen did not require ECMO. Median CRI from birth to 48 h was 0.112 (IQR: 0.082, 0.15). CRI values were significantly lower in newborns that required ECMO versus those who did not (p = 0.0035). Postnatal CRI had the highest AUC (0.85) compared to other prenatal prognostic measures.

CONCLUSION

Humans from newborns to adults share elemental features of the pulsatile waveform that are associated with progression to decompensation. CRI may be helpful when deciding when to initiate ECMO.

LEVEL OF EVIDENCE

Level III.

TYPE OF STUDY

Diagnostic test.

Injectable, self-healable zwitterionic cryogels with sustained microRNA - cerium oxide nanoparticle release promote accelerated wound healing

Diabetics are prone to chronic wounds that have slower healing, and methods of accelerating the wound closure and to ensure protection from infections are critically needed. MicroRNA-146a gets dysregulated in diabetic wounds and injection of this microRNA combined with reactive oxygen species-scavenging cerium oxide nanoparticles (CNPs) can reduce inflammation and improve wound healing; however, a better delivery method than intradermal injections is needed. Here we demonstrate a biomaterial system of zwitterionic cryogels (gels formed below freezing temperatures) laden with CNP-miR146a that are topically applicable, injectable, self-healable, and provide sustained release of the therapeutic molecules. These cryogels are comprised of CBMA or SBMA and HEMA, and do not contain chemical crosslinkers. Properties of the gels can be manipulated by changing monomer type and ratio. These materials have demonstrated efficacy and viability in vivo with a diabetic mouse wound healing model. Overall, these materials have a high potential for application in wound treatments due to their ease of production, antifouling characteristics, durability, topical application, and sustained release mechanics. STATEMENT OF SIGNIFICANCE: This work presents the development of zwitterionic cryogels with unique physical properties including injectability and self-healing, that also offer highly sustained release of nanoparticles over time to improve wound healing in a diabetic mouse model. The nanoparticles are made of cerium oxide, which is known to scavenge reactive oxygen species and reduce oxidative stress, and these particles have been further tagged with a microRNA146a that has been shown to reduce inflammation. Zwitterionic materials are known for their superior antifouling properties and good biocompatibility and ability to incorporate bioactive factors. Given these properties, the use of these materials as wound healing dressings would be exciting, yet to date it has been difficult to prolong the release of bioactive factors from them due to their hydrophilicity. Previously we developed zwitterionic cyrogels with very sustained protein release over time, but those materials were quite brittle and difficult to handle. Here, we demonstrate for the first time that by removing the crosslinker molecule from our reaction and polymerizing gels under cryo-conditions, we are able to form zwitterionic cryogels that are injectable, self-healing, and with sustained release profiles. The sustained release of miRNA146a-tagged cerium oxide nanoparticles from these gels is demonstrated to speed up diabetic wound healing time and significantly reduce inflammation.

Flap repair in congenital diaphragmatic hernia leads to lower rates of recurrence

BACKGROUND

Congenital diaphragmatic hernia (CDH) repair is technically challenging with different approaches for repair. The aim of this study was to compare outcomes between patch and flap repair.

METHODS

CDH repairs performed at a quaternary care children's hospital between 2008 and 2018 were reviewed. Seventy CDH repairs were analyzed after primary repairs were excluded (n = 52). Analysis included proportions or median with interquartile range and chi-square or Wilcoxon rank-sum test.

RESULTS

Comparing patch and flap repairs, demographic characteristics and hernia parameters were similar. Examining outcomes, length of stay, 30-day mortality, and 1-year mortality were all similar between groups, but total/symptomatic recurrence was higher in the patch group (10%/7% vs. 3%/0%), and the median time to recurrence was 3 months. A sub-analysis comparing those who recurred to those who did not demonstrated no significant difference between the two groups.

CONCLUSION

Patients who undergo flap repair have a lower risk of recurrence compared to those who undergo patch repair, and this may be due to the ability of the flap to grow over time with the child.

TYPE OF STUDY

Treatment Study.

LEVEL OF EVIDENCE

III.

Examination of Prenatal Sonographic Findings: Intra-Abdominal Bowel Dilation Predicts Poor Gastroschisis Outcomes

BACKGROUND

Gastroschisis is an anterior abdominal wall defect with variable outcomes. There are conflicting data regarding the prognostic value of sonographic findings.

OBJECTIVES

The aim of this study was to identify prenatal ultrasonographic features associated with poor neonatal outcomes.

METHOD

A retrospective review of 55 patients with gastroschisis from 2007 to 2017 was completed. Ultrasounds were reviewed for extra-abdominal intestinal diameter (EAID) and intra-abdominal intestinal diameter (IAID), echogenicity, visceral content within the herniation, amniotic fluid index, defect size, and abdominal circumference (AC). Ultrasound variables were correlated with full enteral feeding and the diagnosis of a complex gastroschisis.

RESULTS

Bivariate analysis demonstrated an increased time to full enteral feeds with increasing number of surgeries, EAID, and IAID. Additionally, there was a significant relationship between IAID and AC percentile with the diagnosis of complex gastroschisis. On multivariate analysis, only IAID was significant and increasing diameter had a 2.82 (95% CI 1.02-7.78) higher odds of a longer time to full enteral feeds and a 1.2 (95% CI 1.05-1.36) greater odds of the diagnosis of a complex gastroschisis.

CONCLUSIONS

Based on these findings, IAID is associated with a longer time to full enteral feeding and the diagnosis of complex gastroschisis.

Tapering duodenoplasty: a beneficial adjunct in the treatment of congenital duodenal obstruction

Objective

Congenital duodenal obstruction is typically treated by duodenoduodenostomy. Tapering of the dilated segment has been indicated to reduce duodenal dysmotility. The purpose of this study was to review the outcomes between these two approaches.

Methods

We retrospectively reviewed cases of duodenal obstruction repair performed at a quaternary care referral pediatric hospital from 2007 to 2017. The length of stay, time to full enteral feeding, and complications were compared between patients who underwent duodenoduodenostomy with and without tapering duodenoplasty (n=4 and n=35, respectively).

Results

Both groups had similar times to initial enteral feeding (7 days) and full enteral feeding (14 vs. 15 days). Among the 35 patients who underwent duodenoduodenostomy alone, 6 (17%) required a return to the operating room; in contrast, no patients who underwent tapering required a return to the operating room. Of those who returned to the operating room, two underwent tapering at that time because of duodenal dilation and feeding intolerance.

Conclusions

Although limited by the small sample size, this study suggests that patients undergoing tapering duodenoplasty may have a slightly shorter time to full enteral feeding and a lower rate of complications than patients undergoing duodenoduodenostomy alone.

MOMS Plus: Single-Institution Review of Outcomes for Extended BMI Criteria for Open Fetal Repair of Myelomeningocele

BACKGROUND

In utero repair has become an accepted therapy to decrease the rate of ventriculoperitoneal shunting and improve neurologic function in select cases of myelomeningocele. The Management of Myelomeningocele Study (MOMS) trial excluded patients with a BMI >35 due to concerns for increased maternal complications and preterm delivery, limiting the population that may benefit from this intervention.

OBJECTIVES

The aim of this study was to evaluate outcomes associated with extending the maternal BMI criteria to 40 in open fetal repair of myelomeningocele.

METHOD

Retrospective review of fetal closure of myelomeningocele at a quaternary referral center between 2013 and 2016 with maternal BMI ranging from 35 to 40.

RESULTS

Eleven patients with a BMI >35 were identified. The average BMI was 37. The average maternal age at the time of evaluation was 27 years. The average gestational age at fetal surgery was 24 weeks. Gestational age at birth was an average of 32 weeks. There was one perinatal death immediately following the fetal intervention. The shunt rate at 1 year was 45% (5/11 patients).

CONCLUSIONS

In this single-institution review of expanded BMI criteria for fetal repair of myelomeningocele, we did not observe any adverse maternal outcomes associated with maternal obesity; however, the gestational age at delivery was 2 weeks earlier compared to the MOMS trial.

Differential Expression of Transforming Growth Factor-β1 Is Associated With Fetal Regeneration After Myocardial Infarction

BACKGROUND

Global extracellular matrix (ECM)-related gene expression is decreased after myocardial infarction (MI) in fetal sheep when compared with adult sheep. Transforming growth factor (TGF)-β1 is a key regulator of ECM; therefore we hypothesize that TGF-β1 is differentially expressed in adult and fetal infarcts after MI.

METHODS

Adult and fetal sheep underwent MI via ligation of the left anterior descending coronary artery. Expression of TGF-β1 and ECM-related genes was evaluated by ovine-specific microarray and quantitative polymerase chain reaction. Fibroblasts from the left ventricle of adult and fetal hearts were treated with TGF-β1 or a TGF-β1 receptor inhibitor (LY36497) to evaluate the effect of TGF-β1 on ECM-related genes.

RESULTS

Col1a1, col3a1, and MMP9 expression were increased in adult infarcts 3 and 30 days after MI but were upregulated in fetal infarcts only 3 days after MI. Three days after MI elastin expression was increased in adult infarcts. Despite upregulation in adult infarcts both 3 and 30 days after MI, TGF-β1 was not upregulated in fetal infarcts at any time point. Inhibition of the TGF-β1 receptor in adult cardiac fibroblasts decreased expression of col1a1, col3a1, MMP9, elastin, and TIMP1, whereas treatment of fetal cardiac fibroblasts with TGF-β1 increased expression of these genes.

CONCLUSIONS

TGF-β1 is increased in adult infarcts compared with regenerative, fetal infarcts after MI. Although treatment of fetal cardiac fibroblasts with TGF-β1 conveys an adult phenotype, inhibition of TGF-β1 conveys a fetal phenotype to adult cardiac fibroblasts. Decreasing TGF-β1 after MI may facilitate myocardial regeneration by "fetalizing" the otherwise fibrotic, adult response to MI.