374 results on '"Keijzer R"'
Search Results
152. Embryology and anatomy of congenital diaphragmatic hernia.
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De Leon N, Tse WH, Ameis D, and Keijzer R
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- Animals, Female, Humans, Pregnancy, Diaphragm abnormalities, Lung abnormalities, Hernias, Diaphragmatic, Congenital genetics, Hernias, Diaphragmatic, Congenital complications, Hypertension, Pulmonary etiology
- Abstract
Prenatal and postnatal treatment modalities for congenital diaphragmatic hernia (CDH) continue to improve, however patients still face high rates of morbidity and mortality caused by severe underlying persistent pulmonary hypertension and pulmonary hypoplasia. Though the majority of CDH cases are idiopathic, it is believed that CDH is a polygenic developmental defect caused by interactions between candidate genes, as well as environmental and epigenetic factors. However, the origin and pathogenesis of these developmental insults are poorly understood. Further, connections between disrupted lung development and the failure of diaphragmatic closure during embryogenesis have not been fully elucidated. Though several animal models have been useful in identifying candidate genes and disrupted signalling pathways, more studies are required to understand the pathogenesis and to develop effective preventative care. In this article, we summarize the most recent litterature on disrupted embryological lung and diaphragmatic development associated with CDH., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2022. Published by Elsevier Inc.)
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- 2022
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153. Placental Nanoparticle Uptake-On-a-Chip: The Impact of Trophoblast Syncytialization and Shear Stress.
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Abostait A, Tyrrell J, Abdelkarim M, Shojaei S, Tse WH, El-Sherbiny IM, Keijzer R, and Labouta HI
- Subjects
- Female, Pregnancy, Humans, Placenta metabolism, Colforsin pharmacology, Colforsin metabolism, Liposomes metabolism, Lab-On-A-Chip Devices, Carrier Proteins metabolism, Trophoblasts metabolism, Nanoparticles
- Abstract
The placenta is a dynamic and complex organ that plays an essential role in the health and development of the fetus. Placental disorders can affect the health of both the mother and the fetus. There is currently an unmet clinical need to develop nanoparticle-based therapies to target and treat placental disorders. However, little is known about the interaction of nanoparticles (NPs) with the human placenta under biomimetic conditions. Specifically, the impact of shear stress exerted on the trophoblasts (placental epithelial cells) by the maternal blood flow, the gradual fusion of the trophoblasts along the gestation period (syncytialization), and the impact of microvilli formation on the cell uptake of NPs is not known. To this end, we designed dynamic placenta-on-a-chip models using BeWo cells to recapitulate the micro-physiological environment, and we induced different degrees of syncytialization via chemical induction with forskolin. We characterized the degree of syncytialization quantitatively by measuring beta human chorionic gonadotropin (β-hCG) secretion, as well as qualitatively by immunostaining the tight junction protein, ZO-1, and counter nuclear staining. We also characterized microvilli formation under static and dynamic conditions via F-actin staining. We used these models to measure the cell uptake of chondroitin sulfate a binding protein (CSA) conjugated and control liposomes using confocal microscopy, followed by image analysis. Interestingly, exposure of the cells to a dynamic flow of media intrinsically induced syncytialization and microvilli formation compared to static controls. Under dynamic conditions, BeWo cells produced more β-hCG in conditions that increased the cell exposure time to forskolin ( p < 0.005). Our cell uptake results clearly show a combined effect of the exerted shear stress and forskolin treatment on the cell uptake of liposomes as uptake increased in forskolin exposed conditions ( p < 0.05). Overall, the difference in the extent of cell uptake of liposomes among the different conditions clearly displays a need for the development of dynamic models of the placenta that consider the changes in the placental cell phenotype along the gestation period, including syncytialization, microvilli formation, and the expression of different transport and uptake receptors. Knowledge generated from this work will inform future research aiming at developing drug delivery systems targeting the placenta.
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- 2022
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154. The maternal-fetal transfer of passive immunity as a mechanism of transplacental nanoparticle drug delivery for prenatal therapies.
- Author
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Tse WH, Higgins S, Patel D, Xing M, West AR, Labouta HI, and Keijzer R
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- Female, Fetus, Humans, Immunoglobulin G, Infant, Newborn, Placenta, Pregnancy, Chitosan metabolism, Nanoparticles
- Abstract
Nanoparticles administered into the maternal circulation and across the placenta are a potential clinical therapy to treat congenital diseases. The mechanism by which nanoparticles can safely cross the placenta for targeted drug delivery to the fetus remains poorly understood. We demonstrate that the maternal-fetal transfer of passive immunity through the neonatal Fc Receptor (FcRn) can induce the transplacental transfer of chitosan nanoparticles modifed with IgG antibodies (414 ± 27 nm). The transfer of FITC-tagged IgG-modified chitosan nanoparticles was 2.8 times higher ( p = 0.0264) compared to similarly-sized unmodified chitosan nanoparticles (375 ± 17 nm). Co-administration of free IgG competitively diminished the transplacental transfer of IgG-modified nanoparticles, yet unmodified nanoparticles remained unaffected. Colocalization of the FcRn and the IgG-modified chitosan nanoparticles were observed with confocal microscopy. Barrier function before and after nanoparticle administration remained intact as determined by TEER (75-79 Ω cm
2 ) and immmunofluorescence of ZO-1 tight junction proteins. The results provide insight into the clinical applications of nanoparticles for prenatal therapies using the mechanism of the maternal-fetal transfer of passive immunity.- Published
- 2022
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155. Congenital diaphragmatic hernia.
- Author
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Zani A, Chung WK, Deprest J, Harting MT, Jancelewicz T, Kunisaki SM, Patel N, Antounians L, Puligandla PS, and Keijzer R
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- Endoscopy, Female, Humans, Lung abnormalities, Lung diagnostic imaging, Pregnancy, Ultrasonography, Prenatal adverse effects, Hernias, Diaphragmatic, Congenital diagnosis, Hernias, Diaphragmatic, Congenital surgery, Hypertension, Pulmonary diagnosis, Hypertension, Pulmonary etiology, Hypertension, Pulmonary therapy
- Abstract
Congenital diaphragmatic hernia (CDH) is a rare birth defect characterized by incomplete closure of the diaphragm and herniation of fetal abdominal organs into the chest that results in pulmonary hypoplasia, postnatal pulmonary hypertension owing to vascular remodelling and cardiac dysfunction. The high mortality and morbidity rates associated with CDH are directly related to the severity of cardiopulmonary pathophysiology. Although the aetiology remains unknown, CDH has a polygenic origin in approximately one-third of cases. CDH is typically diagnosed with antenatal ultrasonography, which also aids in risk stratification, alongside fetal MRI and echocardiography. At specialized centres, prenatal management includes fetal endoscopic tracheal occlusion, which is a surgical intervention aimed at promoting lung growth in utero. Postnatal management focuses on cardiopulmonary stabilization and, in severe cases, can involve extracorporeal life support. Clinical practice guidelines continue to evolve owing to the rapidly changing landscape of therapeutic options, which include pulmonary hypertension management, ventilation strategies and surgical approaches. Survivors often have long-term, multisystem morbidities, including pulmonary dysfunction, gastroesophageal reflux, musculoskeletal deformities and neurodevelopmental impairment. Emerging research focuses on small RNA species as biomarkers of severity and regenerative medicine approaches to improve fetal lung development., (© 2022. Springer Nature Limited.)
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- 2022
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156. Educational outcomes in school age children with a history of isolated Hirschsprung disease are equivalent to their peers.
- Author
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Cowap M, Derraugh G, Shawyer AC, Balshaw R, Min SAL, and Keijzer R
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- Child, Child, Preschool, Educational Status, Humans, Retrospective Studies, Schools, Academic Success, Hirschsprung Disease
- Abstract
Purpose: The aim of this study was to assess real-world educational outcomes and developmental disorders in patients with a history of Hirschsprung disease compared to an age-matched control group., Methods: With ethics approval (H2016:014) a retrospective cohort study of all children diagnosed with Hirschsprung disease at a single centre from 1992 to 2017 was performed. A 10:1 date-of-birth matched control cohort was constructed from a population-based directory. The educational outcomes were compared using the following measures: Early Developmental Instrument, Grades 3, 7, and 8 assessments, Grade 9 completion, Grade 9 performance, and high school graduation. Fisher's exact tests were used to compare the odds of failure between cases to controls. Only children who reached 4 years of age were included., Results: A total of 75 cases with Hirschsprung disease patients were identified. Patients with Hirschsprung disease were at increased risk of failing to meet expectations on the Early Development Instrument. After entering elementary school, Hirschsprung patients were at no greater risk than their peers of failing to meet expectations on standardized testing or failing to graduate from high school., Conclusion: Using real-world measures of academic success as a surrogate for neurodevelopmental status, our study demonstrates that patients with a history of Hirschsprung disease demonstrated poor neurodevelopmental performance in pre-school, but the educational achievements of patients did not differ from controls once they started school. These promising data can be used to mitigate preconceived notions that patients with Hirschsprung disease require special education, which may be isolating and psychosocially damaging., Competing Interests: Declaration of competing interest None of the authors have conflicts of interest to declare., (Copyright © 2022. Published by Elsevier Inc.)
- Published
- 2022
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157. Musculoskeletal deformities in children with congenital thoracic malformations: a population-based cohort study.
- Author
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Markel M, Derraugh G, Lacher M, Iqbal S, Balshaw R, Lum Min SA, and Keijzer R
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- Child, Cohort Studies, Humans, Retrospective Studies, Esophageal Atresia surgery, Hernias, Diaphragmatic, Congenital surgery, Tracheoesophageal Fistula surgery
- Abstract
Purpose: It is unclear if musculoskeletal deformities observed in patients with congenital diaphragmatic hernia (CDH), congenital lung lesion (CLL) and esophageal atresia/tracheoesophageal fistula (EA/TEF) are associated with the anomaly or are a result of the surgery required to treat the anomaly. This study compared the prevalence of musculoskeletal deformities for: (1) children with congenital thoracic anomalies to controls; (2) CLL to EA/TEF both repaired via thoracotomy; and (3) CLL and EA/TEF to CDH repaired via laparotomy., Methods: We performed a retrospective study of children with CLL, CDH or EA/TEF between 1990 and 2016. Date-of-birth-matched control groups were generated from a population-based dataset. International Classification of Disease codes were used to identify scoliosis and pectus anomalies. We determined Hazard ratios (HR) for cases versus controls., Results: We included 167 cases (CDH n = 82; CLL n = 29; EA/TEF n = 56) and 1670 controls. EA/TEF had a greater risk of scoliosis (HR 5.52, 95%CI 1.49,13.73) and pectus deformities (HR 4.07, 95%CI 1.96,8.45). CDH showed more scoliosis (HR 5.03, 95%CI 1.99,12.74) but not pectus anomalies. Musculoskeletal deformities were not more common in CLL., Conclusion: Children born with CDH or EA/TEF, but not CLL, had more musculoskeletal deformities than controls. The inconsistent association between musculoskeletal deformities and the surgical approach suggested a congenital predisposition., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
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- 2022
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158. Tenascin C is dysregulated in hypoplastic lungs of miR-200b -/- mice.
- Author
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Markel M, Tse WH, DeLeon N, Patel D, Kahnamouizadeh S, Lacher M, Wagner R, and Keijzer R
- Subjects
- Animals, Epithelial-Mesenchymal Transition, Lung abnormalities, Male, Mice, Mice, Knockout, Hernias, Diaphragmatic, Congenital genetics, Hernias, Diaphragmatic, Congenital metabolism, MicroRNAs genetics, Tenascin genetics, Tenascin metabolism
- Abstract
Purpose: We previously demonstrated that absence of miR-200b results in abnormal lung development in congenital diaphragmatic hernia due to imbalance between epithelial and mesenchymal cells. Tenascin C is a highly conserved extracellular matrix protein involved in epithelial to mesenchymal transition, tissue regeneration and lung development. Considering the involvement of Tenascin C and miR-200b and their potential interaction, we aimed to study Tenascin C during lung development in the absence of miR-200b., Methods: We collected lungs of miR-200b
-/- mice (male, 8 weeks). We performed Western blot (WB) analysis (N = 6) and immunofluorescence (N = 5) for Tenascin C and alpha smooth muscle actin and RT-qPCR for Tenascin C gene expression (N = 4)., Results: Using WB analysis, we observed a decreased total protein abundance of Tenascin C in miR-200b-/- lungs (miR-200b+/+ : 3.8 × 107 ± 1 × 107 ; miR-200b-/- : 1.9 × 107 ± 5 × 106 ; p = 0.002). Immunofluorescence confirmed decreased total Tenascin C in miR-200b-/- lungs. Tenascin C was significantly decreased in the mesenchyme but relatively increased in the airways of mutant lungs. Total lung RNA expression of Tenascin C was higher in miR-200b-/- lungs., Conclusion: We report dysregulation of Tenascin C in lungs of miR-200b-/- mice. This suggests that absence of miR-200b results in abnormal Tenascin C abundance contributing to the lung hypoplasia observed in miR-200b-/- mice., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)- Published
- 2022
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159. Congenital lung malformation patients experience respiratory infections after resection: A population-based cohort study.
- Author
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Markel M, Derraugh G, Lacher M, Iqbal S, Balshaw R, Min SAL, and Keijzer R
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- Child, Cohort Studies, Humans, Lung abnormalities, Lung surgery, Retrospective Studies, Bronchopulmonary Sequestration surgery, Cystic Adenomatoid Malformation of Lung, Congenital epidemiology, Cystic Adenomatoid Malformation of Lung, Congenital surgery, Influenza, Human, Lung Diseases congenital, Pneumonia, Respiratory System Abnormalities epidemiology, Respiratory System Abnormalities surgery, Respiratory Tract Infections epidemiology, Respiratory Tract Infections etiology
- Abstract
Purpose: The benefit of elective resection of congenital lung malformations continues to be debated. Proponents of resection endorse a decreased risk of respiratory complications as one indication for surgery. Our study aimed to compare the prevalence of respiratory infections in cases, before and after resection of congenital lung malformations, to controls without a history of congenital lung malformation., Methods: We performed a retrospective cohort study of children born from 1991 to 2007 who underwent congenital lung malformation resection. Patients were identified from Winnipeg´s Surgical Database of Outcomes and Management (WiSDOM), and a 10:1 date-of-birth matched control group was generated from a population-based administrative data repository. International Classification of Disease codes were used to assess pulmonary infection outcomes. Relative rates (RR) were calculated to compare the frequency of pneumonia, respiratory infections and influenza between cases and controls., Results: We included 31 congenital lung malformation cases and 310 controls. Cases consisted of 14 (45.16%) congenital pulmonary airway malformations, 9 (29.03%) bronchopulmonary sequestrations and 8 (25.81%) hybrid lesions. Before resection, pneumonia was more common in cases than controls (RR 6.85; 95%CI 3.89, 11.9), while the risk of acute respiratory infections (RR 1.21; 95%CI 0.79, 1.79) and influenza (RR 0.46; 95%CI 0.01, 3.22) were similar to controls. Post-resection, the risk of pneumonia (RR 9.75; 5.06, 18.50) was still higher in cases than controls, and respiratory infections (RR 1.77; 95%CI 1.20, 2.53) and influenza (RR 3.98; 95%CI 1.48, 9.36) were more common in cases than controls., Conclusion: Our study demonstrated that after resection of congenital lung malformations, children experience more frequent respiratory infections compared to the general population. Resection does not eliminate the increased risk of pneumonia., Competing Interests: Conflict of Interest None of the authors have conflicts of interest to declare., (Copyright © 2022. Published by Elsevier Inc.)
- Published
- 2022
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160. Yes-associated protein is dysregulated during nitrofen-induced hypoplastic lung development due to congenital diaphragmatic hernia.
- Author
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Kahnamoui S, Khoshgoo N, Patel D, Wagner R, and Keijzer R
- Subjects
- Animals, Disease Models, Animal, Gene Expression Regulation, Developmental, Humans, Lung abnormalities, Phenyl Ethers toxicity, Rats, Rats, Sprague-Dawley, YAP-Signaling Proteins, Hernias, Diaphragmatic, Congenital metabolism
- Abstract
Background: Congenital diaphragmatic hernia (CDH) is a birth defect associated with abnormal lung development. Yes-associated protein (YAP) is a core kinase of the Hippo pathway, which controls organ size during development. The absence of YAP protein during lung development results in hypoplastic lungs comparable to the lung phenotype in CDH (Mahoney, Dev Cell 30(2):137-150, 2014). We aimed to describe the expression of YAP during normal and nitrofen-induced abnormal lung development., Methods: Intra-gastric administration of dams with 100 mg of nitrofen was used to induce CDH and abnormal lung development in the embryos. Immunofluorescence was performed to visualize the localization of YAP and p-YAP during lung development (E15, E18, E21). Western Blotting was used to determine the abundance of YAP and p-YAP in E21 control and nitrofen-induced hypoplastic CDH lungs., Results: Immunofluorescence demonstrated cytoplasmic localization of YAP protein in airway epithelial and mesenchymal cells of nitrofen-induced hypoplastic lungs compared to nuclear localization in control lungs. Western Blotting showed a decrease (p = 0.0188) in abundance of YAP (active form) and increase in p-YAP (inactive form) in hypoplastic lungs compared to control lungs., Conclusion: Our results demonstrate that YAP protein is mostly phosphorylated, inactive, and expressed in the cytoplasm at the later stages of nitrofen-induced hypoplastic lung development indicating that the alteration in regulation of YAP can be associated with the pathogenesis of abnormal lung development in experimental CDH., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
- Published
- 2022
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161. Misoprostol treatment prevents hypoxia-induced cardiac dysfunction through a 14-3-3 and PKA regulatory motif on Bnip3.
- Author
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Martens MD, Seshadri N, Nguyen L, Chapman D, Henson ES, Xiang B, Falk L, Mendoza A, Rattan S, Field JT, Kawalec P, Gibson SB, Keijzer R, Saleem A, Hatch GM, Doucette CA, Karch JM, Dolinsky VW, Dixon IM, West AR, Rampitsch C, and Gordon JW
- Subjects
- Animals, Disease Models, Animal, Humans, Misoprostol pharmacology, Oxytocics pharmacology, Rats, Transfection, 14-3-3 Proteins metabolism, Heart Diseases drug therapy, Membrane Proteins metabolism, Misoprostol therapeutic use, Mitochondrial Proteins metabolism, Oxytocics therapeutic use
- Abstract
Systemic hypoxia is a common element in most perinatal emergencies and is a known driver of Bnip3 expression in the neonatal heart. Bnip3 plays a prominent role in the evolution of necrotic cell death, disrupting ER calcium homeostasis and initiating mitochondrial permeability transition (MPT). Emerging evidence suggests a cardioprotective role for the prostaglandin E1 analog misoprostol during periods of hypoxia, but the mechanisms for this protection are not completely understood. Using a combination of mouse and cell models, we tested if misoprostol is cardioprotective during neonatal hypoxic injury by altering Bnip3 function. Here we report that hypoxia elicits mitochondrial-fragmentation, MPT, reduced ejection fraction, and evidence of necroinflammation, which were abrogated with misoprostol treatment or Bnip3 knockout. Through molecular studies we show that misoprostol leads to PKA-dependent Bnip3 phosphorylation at threonine-181, and subsequent redistribution of Bnip3 from mitochondrial Opa1 and the ER through an interaction with 14-3-3 proteins. Taken together, our results demonstrate a role for Bnip3 phosphorylation in the regulation of cardiomyocyte contractile/metabolic dysfunction, and necroinflammation. Furthermore, we identify a potential pharmacological mechanism to prevent neonatal hypoxic injury., (© 2021. The Author(s).)
- Published
- 2021
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162. Respiratory outcomes in the first 10 years of life in children with gastroschisis: A retrospective cohort study.
- Author
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Asemota O, Derraugh G, Levesque M, Iqbal S, Balshaw R, Lum Min SA, and Keijzer R
- Subjects
- Child, Cohort Studies, Humans, Retrospective Studies, Gastroschisis epidemiology, Pneumonia, Respiratory Tract Infections
- Abstract
Background: Little attention has been given to the long-term respiratory outcomes of children with gastroschisis. The purpose of this study was to determine if gastroschisis survivors have more respiratory illnesses in their first 10 years of life compared with age-matched controls., Methods: We performed a retrospective cohort study of all gastroschisis children born in Manitoba between 1991 and 2017. Gastroschisis cases were identified from a clinical database, and a date of birth-matched control cohort was constructed from a population-based data repository. International Classification of Disease codes were used to compare the risk and frequency of respiratory diagnoses for children with gastroschisis to date of birth-matched controls from 0-5 years of age and 5-10 years of age., Results: The 0-5 years of age analysis included 117 gastroschisis cases and 1205 date of birth-matched controls; children with gastroschisis had a higher risk of asthma (relative risk [RR] = 1.46; 95% confidence interval [CI]: 1.03, 2.55; p = .029), acute bronchitis/bronchiolitis (RR = 1.61; 95% CI: 1.27, 2.03; p < .001), pneumonia (RR = 1.99; 95% CI: 1.45, 2.72; p < .001), viral pneumonia (RR = 5.15; 95% CI: 1.79, 14.81; p = .007), and pneumonia due to unspecified organism (RR = 2.06; 95% CI: 1.45, 2.92; p < .001). Gastroschisis children 0-5 years of age were also diagnosed more frequently with bronchitis/bronchiolitis (RR = 2.14; 95% CI: 1.79, 2.57; p < .001) and viral pneumonia (RR = 8.10; 95% CI: 3.79, 17.31; p < .001). The 5-10 years of age analysis included 73 cases and 738 controls; no difference in the risk of respiratory illness was found for gastroschisis cases and controls in this age group. However, gastroschisis cases were more frequently diagnosed with bacterial pneumonia (RR = 3.03; 95% CI: 1.67, 5.51; p < .001) and influenza (RR = 3.03; 95% CI: 1.67, 5.51; p < .001)., Conclusion: Our study shows that children with gastroschisis have an increased risk of asthma and respiratory infections compared with children without gastroschisis, most noticeably in the first 5 years of life., (© 2021 Wiley Periodicals LLC.)
- Published
- 2021
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163. Formal Research Training - An Essential Aspect for Surgical Residency?
- Author
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Wagner R, Montalva L, Zani A, and Keijzer R
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- Biomedical Research education, Internship and Residency, Specialties, Surgical education
- Abstract
Competing Interests: The authors report no conflicts of interest.
- Published
- 2021
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164. The RNA-binding protein Quaking regulates multiciliated and basal cell abundance in the developing lung.
- Author
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Ameis D, Liu F, Kirby E, Patel D, and Keijzer R
- Subjects
- Animals, Female, Protein Isoforms, RNA-Binding Proteins genetics, Rats, Rats, Sprague-Dawley, Cell Differentiation, Cilia physiology, Gene Expression Regulation, Developmental, Lung embryology, Lung metabolism, RNA-Binding Proteins metabolism
- Abstract
RNA-binding proteins (RBPs) form complexes with RNA, changing how the RNA is processed and thereby regulating gene expression. RBPs are important sources of gene regulation during organogenesis, including the development of lungs. The RBP called Quaking (QK) is critical for embryogenesis, yet it has not been studied in the developing lung. Here, we show that QK is widely expressed during rat lung development and into adulthood. The QK isoforms QK5 and QK7 colocalize to the nuclei of nearly all lung cells. QK6 is present in the nuclei and cytoplasm of mesenchymal cells and is only present in the epithelium during branching morphogenesis. QK knockdown in embryonic lung explants caused a greater number of multiciliated cells to appear in the airways, at the expense of basal cells. The mRNA of multiciliated cell genes and the abundance of FOXJ1/SOX2+ cells increased after knockdown, whereas P63/SOX2+ cells decreased. The cytokine IL-6, a known regulator of multiciliated cell differentiation, had increased mRNA levels after QK knockdown, although protein levels remained unchanged. Further studies are necessary to confirm whether QK acts as a blocker for the IL-6-induced differentiation of basal cells into multiciliated cells, and a conditional QK knockout would likely lead to additional discoveries on QK's role during lung development.
- Published
- 2021
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165. Publisher's Note: "A cryogenic-helium pipe flow facility with unique double-line molecular tagging velocimetry capability" [Rev. Sci. Instrum. 91, 053901 (2020)].
- Author
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Sanavandi H, Bao S, Zhang Y, Keijzer R, Guo W, and Cattafesta LN 3rd
- Published
- 2021
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166. The prevalence of hearing loss in children with congenital diaphragmatic hernia: A longitudinal population-based study.
- Author
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Alenazi A, Derraugh G, Levesque M, Morris MI, Shawyer AC, Lum Min SA, and Keijzer R
- Subjects
- Child, Female, Humans, Odds Ratio, Parturition, Pregnancy, Prevalence, Retrospective Studies, Hearing Loss epidemiology, Hearing Loss etiology, Hernias, Diaphragmatic, Congenital complications, Hernias, Diaphragmatic, Congenital epidemiology
- Abstract
Background: The true prevalence of hearing loss among children with congenital diaphragmatic hernia (CDH) is unknown, with some studies reporting rates up to 60%., Purpose: The purpose of this study was to determine the prevalence of hearing loss among children with CDH and compare it to age-matched controls., Methods: We used population-based datasets to compare the number of hearing loss diagnoses in children younger than 10 years-of-age born between 1992 and 2009 with CDH to date-of-birth matched controls without CDH. Factors associated with CDH disease severity were analyzed to determine their effect on the prevalence of hearing loss. A sensitivity analysis was performed to determine if selection bias of improved care over the course of the study affected hearing loss in CDH patients. The prevalences of hearing loss were compared using Fisher's exact tests and statistical significance was defined as p < 0.05., Results: A total of 529 children, 38 CDH cases and their 491 date-of-birth matched controls, met the inclusion criteria. Hearing loss was found in 7 children with CDH (18.4%) compared to 26 (5.3%) controls; the risk ratio (RR) of hearing loss was 3.48 (95%CI = 1.61-7.49, p = 0.006). There was no association between CDH disease severity and hearing loss., Conclusions: CDH is associated with hearing loss compared to the general population. Our results suggest that congenital factors may contribute to hearing loss in CDH more than perinatal exposures., Level of Evidence: 3., (Copyright © 2020 Elsevier Inc. All rights reserved.)
- Published
- 2021
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167. Epithelial cell-adhesion protein cadherin 26 is dysregulated in congenital diaphragmatic hernia and congenital pulmonary airway malformation.
- Author
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Wagner R, Li H, Ayoub L, Kahnamoui S, Patel D, Stefanovici C, Lacher M, and Keijzer R
- Subjects
- Animals, Cadherins genetics, Disease Models, Animal, Down-Regulation, Epithelial Cells metabolism, Hernias, Diaphragmatic, Congenital genetics, Humans, Infant, Infant, Newborn, Lung metabolism, Lung Diseases genetics, Mice, Rats, Rats, Sprague-Dawley, Cadherins metabolism, Hernias, Diaphragmatic, Congenital metabolism, Lung abnormalities, Lung Diseases metabolism
- Abstract
Background: Congenital diaphragmatic hernia (CDH) and congenital pulmonary airway malformation (CPAM) are two inborn pathologies of the lung of unknown origin. Alterations of gene expression in airway epithelial cells are involved in the pathobiology of both diseases. We previously found decreased expression of the epithelial cell adhesion protein cadherin 26 (CDH26) in hypoplastic mice lungs. Here, our objective was to describe the expression and localization of CDH26 in hypoplastic CDH lungs and hyperproliferative CPAM tissues., Methods: After ethical approval, we used human lung tissues from CDH and CPAM cases and age-matched control samples from a previously established biobank. Furthermore, lungs from the nitrofen rat model of CDH were included in the study. We performed immunohistochemistry and western blot analysis with antibodies against CDH26 to examine protein localization and abundance. Statistical analysis was performed using Mann-Whitney U test with significance set at p < 0.05., Results: We observed an overexpression of CDH26 within the epithelium of cystic CPAM lesions compared to normal airways within the same lung and compared to control lungs. Western blot demonstrated a downregulation of CDH26 in the nitrofen rat model of CDH compared to healthy controls. Immunohistochemistry could not show consistent differences between CDH and control in human and rat lungs. In the studied human lung samples, CDH26 was localized to the apical part of the airway epithelial cells., Conclusion: CDH26 is differentially expressed in human CPAM lung tissues and may be downregulated in nitrofen-induced hypoplastic rat lungs compared to control lungs. Disruption of CDH26 associated pathways in lung development may be involved in the pathogenesis of lung hypoplasia or cystic lung disease.
- Published
- 2021
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168. miR-200 family expression during normal and abnormal lung development due to congenital diaphragmatic hernia at the later embryonic stage in the nitrofen rat model.
- Author
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Mulhall D, Khoshgoo N, Visser R, Iwasiow B, Day C, Zhu F, Eastwood P, and Keijzer R
- Subjects
- Animals, Disease Models, Animal, Female, Hernias, Diaphragmatic, Congenital pathology, In Situ Hybridization, Fluorescence, Lung pathology, Phenyl Ethers, Rats, Rats, Sprague-Dawley, Real-Time Polymerase Chain Reaction, Gene Expression genetics, Hernias, Diaphragmatic, Congenital embryology, Hernias, Diaphragmatic, Congenital genetics, Lung embryology, MicroRNAs genetics
- Abstract
Introduction: Congenital diaphragmatic hernia (CDH) is a life-threatening disease associated with pulmonary hypoplasia. CDH occurs approximately 1 in every 2000-3000 live births, and the pathophysiology is unknown. MicroRNAs are short, non-coding RNAs that control gene expression through post-transcriptional regulation. Based on our previous work, we hypothesized that the miR-200 family is differentially expressed in normal and abnormal lung development. We aimed to examine the expression of the miR-200 family during normal and hypoplastic lung development due to CDH., Methods: We performed reverse transcriptase polymerase chain reaction (RT-qPCR) and fluorescent in situ hybridization (FISH) to study the expression levels and distribution of the miR-200 family members on embryonic day 21 (E21) rat control and nitrofen-induced hypoplastic CDH lungs., Results: RT-qPCR showed up-regulation of miR-200a in hypoplastic CDH lungs. FISH showed contrasting expression patterns for miR- 200a, miR-200c, and miR-429 between control and hypoplastic CDH lungs, while we could not detect miR-141 in control and hypoplastic CDH lungs., Conclusion: We demonstrate a specific expression pattern of miR-200 family members in hypoplastic CDH lungs different from control lungs. This study suggests that disruption of miR-200 family expression plays a role in the pathogenesis of pulmonary hypoplasia associated with CDH.
- Published
- 2020
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169. High-frequency vs. conventional ventilation at the time of CDH repair is not associated with higher mortality and oxygen dependency: a retrospective cohort study.
- Author
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Derraugh G, Levesque M, Schantz D, Sesha M, Minski J, Baier J, Morris MI, Shawyer AC, Balshaw R, Lum Min SA, and Keijzer R
- Subjects
- Canada epidemiology, Female, Follow-Up Studies, Hernias, Diaphragmatic, Congenital mortality, High-Frequency Ventilation methods, Humans, Infant, Newborn, Male, Retrospective Studies, Survival Rate trends, Hernias, Diaphragmatic, Congenital surgery, Herniorrhaphy methods, Oxygen metabolism, Respiration, Artificial methods
- Abstract
Purpose: The VICI-trial reported that in patients with congenital diaphragmatic hernia (CDH), mortality or bronchopulmonary dysplasia (BPD) were equivalent using conventional mechanical ventilation (CMV) and high-frequency oscillatory ventilation. The purpose of this study was to determine if the mode of ventilation at the time of CDH repair affected mortality or oxygen dependence at 28 days., Methods: We performed a retrospective cohort study of infants born wih CDH from 1991 to 2015. A generalized linear model was applied to the data using a propensity score analysis., Results: Eighty patients met the inclusion criteria; at the time of surgery 39 (48.8%) patients were on HFV and 41 (51.3%) patients were on CMV. In the HFV group, 16 (47.1%) patients remained oxygen dependent and there were 5 (12.8%) deaths at 28 days. In the CMV group, 5 (12.2%) patients remained oxygen dependent at 28 days but none had died. The base model demonstrated that the HFV group had increased rates of oxygen dependence [OR = 6.40 (2.13, 22.2), p = 0.002]. However, after propensity score analysis, we found no difference between HFV and CMV., Conclusion: Our study suggests that in infants with CDH, there is no significant difference between HFV and CMV in oxygen dependency or death.
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- 2020
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170. Misoprostol attenuates neonatal cardiomyocyte proliferation through Bnip3, perinuclear calcium signaling, and inhibition of glycolysis.
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Martens MD, Field JT, Seshadri N, Day C, Chapman D, Keijzer R, Doucette CA, Hatch GM, West AR, Ivanco TL, and Gordon JW
- Subjects
- Animals, Animals, Newborn, Calcium metabolism, Cell Hypoxia drug effects, Cell Nucleus drug effects, Cell Proliferation drug effects, Gene Expression Regulation drug effects, Male, Myocytes, Cardiac cytology, Myocytes, Cardiac drug effects, NFATC Transcription Factors metabolism, Rats, Long-Evans, Calcium Signaling drug effects, Cell Nucleus metabolism, Glycolysis drug effects, Membrane Proteins metabolism, Misoprostol pharmacology, Mitochondrial Proteins metabolism, Myocytes, Cardiac metabolism
- Abstract
Systemic hypoxia resulting from preterm birth, altered lung development, and cyanotic congenital heart disease is known to impede the regulatory and developmental pathways in the neonatal heart. While the molecular mechanisms are still unknown, hypoxia induces aberrant cardiomyocyte proliferation, which may be initially adaptive, but can ultimately program the heart to fail in early life. Recent evidence suggests that the prostaglandin E1 analogue, misoprostol, is cytoprotective in the hypoxia-exposed neonatal heart by impacting alternative splicing of the Bcl-2 family member Bnip3, resulting in the generation of a variant lacking the third exon (Bnip3ΔExon3 or small Nip; sNip). Using a rodent model of neonatal hypoxia, in combination with rat primary neonatal cardiomyocytes (PVNCs) and H9c2 cells, we sought to determine if misoprostol can prevent cardiomyocyte proliferation and what the key molecular mechanisms might be in this pathway. In PVNCs, exposure to 10% oxygen induced myocyte proliferation concurrent with molecular markers of cell-cycle progression, such as Cyclin-D1, which were prevented by misoprostol treatment. Furthermore, we describe a critical role for sNip in opposing cardiomyocyte proliferation through several mechanisms, including reduced expression of the proliferative MEF2C-myocardin-BMP10 pathway, accumulation of nuclear calcium leading to NFATc3 activation, and increased expression of the cardiac maturation factor BMP2. Intriguingly, misoprostol and sNip inhibited hypoxia-induced glycolytic flux, which directly influenced myocyte proliferation. These observations were further supported by knockdown studies, where hypoxia-induced cardiomyocyte proliferation is restored in misoprostol-treated cells by an siRNA targeting sNip. Finally, in postnatal day (PND)-10 rat pups exposed to hypoxia, we observed histological evidence of increased nuclei number and increased PPH3 staining, which were completely attenuated by misoprostol treatment. Collectively, this data demonstrates how neonatal cardiomyocyte proliferation can be pharmacologically modulated by misoprostol treatment, which may have important implications for both neonatal and regenerative medicine., Competing Interests: Declaration of Competing Interest None., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)
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- 2020
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171. Long-Term Health-Related Quality of Life in Survivors of Congenital Diaphragmatic Hernia.
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Derraugh G, Lum Min SA, and Keijzer R
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- Adolescent, Case-Control Studies, Child, Child, Preschool, Female, Humans, Male, Surveys and Questionnaires, Hernias, Diaphragmatic, Congenital psychology, Quality of Life
- Abstract
The health-related quality of life (HRQoL) of survivors of congenital diaphragmatic hernia (CDH) is presently unknown. Literature prior to 2015 suggests that CDH survivors have worse HRQoL compared with the general population. However, due to changes in the diagnosis, management, and follow-up of CDH patients, this may no longer be true. The objective of this review was to determine what recent literature suggests regarding the HRQoL of CDH survivors. We reviewed all studies published between April 9, 2015, and April 6, 2020, that described the HRQoL of CDH survivors. Studies were identified using PubMed, and the references of the identified papers were searched for additional studies eligible for inclusion. Seven studies describing HRQoL in CDH survivors using validated measures of HRQoL for children, PedsQL (Pediatric Quality of Life Inventory), KIDSCREEN-52, and Comprehensive Quality of Life Scale - School Version were examined. The findings were disparate. One study suggested that CDH survivors had better than average HRQoL scores, three studies found patients and controls had equivalent scores, and two studies reported poor outcomes for CDH patients. The final study found no effect of disease severity on HRQoL, as determined by prenatal ultrasound. Evidence published between 2015 and 2020 suggests that CDH patients have an HRQoL equivalent to the general population., Competing Interests: None declared., (Georg Thieme Verlag KG Stuttgart · New York.)
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- 2020
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172. Standardizing congenital diaphragmatic hernia care in Canada: Implementing national clinical practice guidelines.
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LaRusso K, Baird R, Keijzer R, Skarsgard E, and Puligandla P
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- Canada, Guideline Adherence, Humans, Reference Standards, Surveys and Questionnaires, Hernias, Diaphragmatic, Congenital therapy, Practice Guidelines as Topic standards
- Abstract
Purpose: We sought to identify implementation barriers and opportunities to increase utilization of the Canadian Congenital Diaphragmatic Hernia (CDH) Collaborative's clinical practice guideline., Methods: A validated readiness assessment was sent via SurveyMonkey™ to CAPSNet site coordinators and local CDH stakeholders. The survey was open from 11/2018 to 02/2019. Data and responses were analyzed using descriptive statistics (REB 2019-4753)., Results: Eighty-six responses were received, of which 65% (n = 56/86) were fully completed. The greatest number of responses came from neonatology (n = 27), pediatric surgery (n = 25), and respiratory therapy (n = 10). Seventy-eight percent (n = 67/86) of respondents were aware of the CDH guideline, and 63% (n = 54/86) used the entire guideline, while 23% (n = 20/86) used only certain sections. Besides recommendations pertaining to fetal intervention and ECLS, interdisciplinary long-term surveillance and prenatal diagnosis were considered most difficult to implement owing to funding limitations. Most respondents (n = 49/56; 87.5%) felt they could implement >75% of the recommendations. Establishing common team goals [i.e., minimize care variations] (n = 33/58;57%), provider buy-in [commitment of all health professionals to the guideline] (n = 28/58;48%), and regular compliance assessment (n = 23/58;40%) would increase uptake., Conclusion: There is national awareness of the CDH guideline. Implementation strategies ensuring common team goals, provider buy-in, and regular compliance assessment should increase guideline uptake/utilization. Consolidating funding for interdisciplinary long-term surveillance and prenatal diagnosis is necessary for any site-specific implementation strategy., Level of Evidence: Level 4 qualitative, survey., (Copyright © 2020 Elsevier Inc. All rights reserved.)
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- 2020
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173. Magnamosis for esophageal atresia is associated with anastomotic strictures requiring an increased number of dilatations.
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Wolfe E, Zidane M, Hancock BJ, Lum Min SA, Zaritzky M, and Keijzer R
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- Canada, Child, Dilatation, Humans, Anastomosis, Surgical instrumentation, Anastomosis, Surgical methods, Esophageal Atresia surgery, Magnets, Tracheoesophageal Fistula surgery
- Abstract
Background/purpose: Magnamosis is a novel technique which utilizes high power magnets to anastomose the esophageal ends in children with esophageal atresia (EA) with or without a tracheoesophageal fistula (TEF), theoretically avoiding the need for thoracotomy. The objective of this study was to compare anastomotic stricture formation requiring dilatation after magnamosis versus after conventional anastomosis., Methods: Our center treated the first 3 cases of EA ± TEF with magnamosis in Canada. One was unsuccessful and excluded from our study. The number of postintervention dilatations was compared to controls from our database, which includes all children with EA ± TEF treated between 1991 and 2015. The controls had EA ± TEF treated with pouch-to-end anastomosis or colonic interposition (n = 65). Mann-Whitney U tests were used with p < 0.05 being significant., Results: The 2 magnamosis cases had a mean of 13.5 dilatations, compared to 2.6 for the controls. Those managed with pouch-to-end anastomosis or colonic interposition had a mean of 2.3 and 2.7 dilatations, respectively. We found that the cases required more dilatations than controls (p = 0.022) and pouch-to-end anastomosis (p = 0.021), but not than colonic interposition (p = 0.106)., Conclusion: Our results indicate that magnamosis is associated with more postintervention dilatations than conventional anastomotic techniques, suggesting that magnamosis results in more frequent and/or more resilient anastomotic strictures., Level of Evidence: 3., (Copyright © 2020 Elsevier Inc. All rights reserved.)
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- 2020
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174. A cryogenic-helium pipe flow facility with unique double-line molecular tagging velocimetry capability.
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Sanavandi H, Bao S, Zhang Y, Keijzer R, Guo W, and Cattafesta LN 3rd
- Abstract
Cryogenic helium-4 has extremely small kinetic viscosity, which makes it a promising material for high Reynolds (Re) number turbulence research in compact laboratory apparatus. In its superfluid phase (He II), helium has an extraordinary heat transfer capability and has been utilized in various scientific and engineering applications. In order to unlock the full potential of helium in turbulence research and to improve our understanding of the heat transfer mechanism in He II, a flow facility that allows quantitative study of helium heat-and-mass transfer processes is needed. Here, we report our work in assembling and testing a unique helium pipe-flow facility that incorporates a novel double-line molecular tagging velocimetry (DL-MTV) system. This flow facility allows us to generate turbulent pipe flows with Re above 107, and it can also be adapted to produce heat-induced counterflow in He II. The DL-MTV system, which is based on the generation and tracking of two parallel thin He
2 * molecular tracer lines with an adjustable separation distance, allows us to measure not only the velocity profile but also both the transverse and longitudinal spatial velocity structure functions. We have also installed a differential pressure sensor on the flow pipe for pressure drop measurements. The testing results of the flow facility and the measuring instruments are presented. We discuss how this facility will allow us to solve some outstanding problems in the helium heat-and-mass transfer topic area.- Published
- 2020
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175. Congenital diaphragmatic hernia: current management strategies from antenatal diagnosis to long-term follow-up.
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Kirby E and Keijzer R
- Subjects
- Female, Fetoscopy methods, Follow-Up Studies, Hernias, Diaphragmatic, Congenital diagnosis, Humans, Infant, Newborn, Pregnancy, Time Factors, Disease Management, Fetus diagnostic imaging, Hernias, Diaphragmatic, Congenital surgery, Practice Guidelines as Topic, Prenatal Diagnosis methods
- Abstract
Congenital diaphragmatic hernia (CDH) is a developmental birth defect consisting of a diaphragmatic defect and abnormal lung development. CDH complicates 2.3-2.8 per 10,000 live births. Despite efforts to standardize clinical practice, management of CDH remains challenging. Frequent re-evaluation of clinical practices in CDH reveals that management of CDH is evolving from one of postnatal stabilization to prenatal optimization. Translational research reveals promising avenues for in utero therapeutic intervention, including fetoscopic endoluminal tracheal occlusion. These remain highly experimental and demand improved antenatal diagnostics. Timely diagnosis of CDH and identification of severely affected fetuses allow time for delivery planning or in utero therapeutics. Optimal perinatal care and surgical treatment strategies are highly debated. Improved CDH mortality rates have placed increased emphasis on identifying and monitoring the long-term sequelae of disease throughout childhood and into adulthood. We review the current management strategies for CDH, highlighting where progress has been made, and where future developments have the potential to revolutionize care in this vulnerable patient population.
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- 2020
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176. Can circular RNAs be used as prenatal biomarkers for congenital diaphragmatic hernia?
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Wagner R, Jha A, Ayoub L, Kahnamoui S, Patel D, Mahood TH, Halayko AJ, Lacher M, Pascoe CD, and Keijzer R
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- Biomarkers, Female, Humans, Pregnancy, RNA, Circular, Hernias, Diaphragmatic, Congenital diagnostic imaging, Hernias, Diaphragmatic, Congenital genetics
- Abstract
Competing Interests: Conflict of interest: R. Wagner has nothing to disclose. Conflict of interest: A. Jha has nothing to disclose. Conflict of interest: L. Ayoub has nothing to disclose. Conflict of interest: S. Kahnamoui has nothing to disclose. Conflict of interest: D. Patel has nothing to disclose. Conflict of interest: T.H. Mahood has nothing to disclose Conflict of interest: A.J. Halayko has nothing to disclose. Conflict of interest: M. Lacher has nothing to disclose. Conflict of interest: C.D. Pascoe has nothing to disclose. Conflict of interest: R. Keijzer has nothing to disclose.
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- 2020
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177. Asthma Medication Use in Congenital Diaphragmatic Hernia Survivors: A Retrospective Population Level Data Analysis.
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Levesque M, Lum Min SA, Morris MI, Shawyer AC, and Keijzer R
- Subjects
- Administration, Inhalation, Adrenal Cortex Hormones therapeutic use, Case-Control Studies, Child, Child, Preschool, Follow-Up Studies, Humans, Infant, Infant, Newborn, Office Visits, Retrospective Studies, Risk Factors, Asthma complications, Asthma drug therapy, Bronchodilator Agents therapeutic use, Hernias, Diaphragmatic, Congenital complications
- Abstract
Introduction: The purpose of this study was to determine if congenital diaphragmatic hernia (CDH) survivors had worse long-term respiratory outcomes compared with age-matched controls, as measured by inhaled bronchodilator use, inhaled steroid use, and asthma-related physician visits., Materials and Methods: We performed a retrospective case-control study of infants with isolated CDH from 1991 to 2013. The primary outcome measures were inhaled bronchodilator prescriptions, inhaled steroid prescriptions, and asthma-related physician visits between 0 and 5 years of age and between 5 and 10 years of age. Subgroup analysis compared the same outcomes for CDH patients grouped by: birth weight, gestational age, side of defect, defect size, liver herniation, hernia sac, and pulmonary hypertension., Results: Fifty-six patients with CDH and 753 age-matched controls met the inclusion criteria for the 0 to 5 years of age analysis. Between 0 and 5 years of age, more CDH survivors were prescribed an inhaled bronchodilator (odds ratio [OR] = 2.47[1.38-4.48], p = 0.001) and inhaled steroid (OR = 2.03[1.07-3.74], p = 0.03), and had an asthma-related physician visit (OR = 1.92[1.00-3.56], p = 0.04). Thirty-eight cases and 491 controls met the inclusion criteria for the 5 to 10 years of age analysis. Between 5 and 10 years of age, CDH survivors were not more likely to be prescribed inhaled bronchodilators, inhaled steroids, or have an asthma-related physician visit. Among the CDH patients, we did not find a clinical characteristic associated with increased inhaled bronchodilator or steroid prescriptions at any age., Conclusion: A history of CDH is associated with higher rates of inhaled bronchodilator prescriptions, inhaled steroid prescriptions, and asthma-related physician visits from 0 to 5 years of age compared with age-matched controls. However, this difference resolves by 5 to 10 years of age., Competing Interests: None declared., (Georg Thieme Verlag KG Stuttgart · New York.)
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- 2020
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178. Basic and translational science advances in congenital diaphragmatic hernia.
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Wagner R, Montalva L, Zani A, and Keijzer R
- Subjects
- Animals, Disease Models, Animal, Epigenesis, Genetic, Fetal Therapies, Hernias, Diaphragmatic, Congenital genetics, Hernias, Diaphragmatic, Congenital metabolism, Humans, MicroRNAs, Prenatal Diagnosis, Trachea surgery, Translational Research, Biomedical, Vascular Remodeling, Fetoscopy, Hernias, Diaphragmatic, Congenital therapy, Hypertension, Pulmonary therapy, Stem Cell Transplantation
- Abstract
Congenital Diaphragmatic Hernia (CDH) is a birth defect that is characterized by lung hypoplasia, pulmonary hypertension and a diaphragmatic defect that allows herniation of abdominal organs into the thoracic cavity. Although widely unknown to the public, it occurs as frequently as cystic fibrosis (1:2500). There is no monogenetic cause, but different animal models revealed various biological processes and epigenetic factors involved in the pathogenesis. However, the pathobiology of CDH is not sufficiently understood and its mortality still ranges between 30 and 50%. Future collaborative initiatives are required to improve our basic knowledge and advance novel strategies to (prenatally) treat the abnormal lung development. This review focusses on the genetic, epigenetic and protein background and the latest advances in basic and translational aspects of CDH research., (Copyright © 2019 Elsevier Inc. All rights reserved.)
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- 2020
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179. Correction to: Myocardin regulates mitochondrial calcium homeostasis and prevents permeability transition.
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Mughal W, Martens M, Field J, Chapman D, Huang J, Rattan S, Hai Y, Cheung KG, Kereliuk S, West AR, Cole LK, Hatch GM, Diehl-Jones W, Keijzer R, Dolinsky VW, Dixon IM, Parmacek MS, and Gordon JW
- Abstract
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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- 2020
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180. First steps in the development of a liquid biopsy in situ hybridization protocol to determine circular RNA biomarkers in rat biofluids.
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Kirby E, Tse WH, Patel D, and Keijzer R
- Subjects
- Animals, Biomarkers metabolism, Disease Models, Animal, Female, Hernias, Diaphragmatic, Congenital diagnosis, Liquid Biopsy, Pregnancy, Rats, Rats, Sprague-Dawley, Hernias, Diaphragmatic, Congenital metabolism, Hernias, Diaphragmatic, Congenital pathology, In Situ Hybridization methods, RNA, Circular metabolism
- Abstract
Purpose: Epigenetic factors are involved in the pathogenesis of congenital diaphragmatic hernia (CDH). Circular RNAs (circRNAs) are epigenetic regulators amenable to biomarker profiling. Here, we aimed to develop a liquid biopsy protocol to detect pathognomonic circRNA changes in biofluids., Methods: Our protocol is adapted from the existing BaseScope™ in situ hybridization technique. Rat biofluids were fixed in a gelatin-coated 96-well plate with formalin. Probes were designed to target circRNAs with significant fold change in nitrofen-induced CDH. FastRED fluorescence was assessed using a plate reader and confirmed with confocal microscopy. We tested maternal serum and amniotic fluid samples from control and nitrofen-treated rats., Results: We detected circRNAs in rat serum and amniotic fluid from control and CDH (nitrofen-treated) rats using fluorescent readout. CircRNA signal was observed in fixed biofluids as fluorescent punctate foci under confocal laser scanning microscopy. This was confirmed by comparison to BaseScope™ lung tissue sections. Signal was concentration dependent and DNase resistant., Conclusion: We successfully adapted BaseScope™ to detect circRNAs in rat biofluids: serum and amniotic fluid. We detected signal from probes targeted to circRNAs that are dysregulated in rat CDH. This work establishes the preliminary feasibility of circRNA detection in prenatal diagnostics.
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- 2019
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181. Best practices for enhancing surgical research: a perspective from the Canadian Association of Chairs of Surgical Research
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Sener A, Anderson CC, Auger FA, Barralet J, Brindle M, Cayabyab FS, Fehlings MG, Lacombe L, Perrault LP, Sabbagh R, Seely AJ, Wallace C, Ellsmere J, and Keijzer R
- Subjects
- Canada, Humans, Surveys and Questionnaires, Attitude of Health Personnel, Biomedical Research, General Surgery
- Abstract
Summary: The Canadian Association of Chairs of Surgical Research was created in 2014, with representation from every departmental surgical research committee across Canada, to establish Canadian surgical research as a beacon for health care innovation and to propose solutions for the daily challenges facing surgeon-researchers. Our key mandate has been to identify challenges for surgeons and scientists performing research to prevent further erosion of this vital area of activity that benefits patients, health care service providers and Canadian society. This article outlines the findings of a nationwide survey sent to all members of departments of surgery across Canada, seeking input on current threats and potential solutions. The results suggest that surgical research in Canada is experiencing a decline in funding and an increase in challenges affecting research productivity of academic surgeons, such as pressures to be clinically active, unpredictable surgical schedules, growing administrative demands, and increasing complexity of patient populations. Although surgeons are productive in their research endeavours, institutional changes and sharing of best practices are needed to ensure sustainable growth of research programs., Competing Interests: M. Brindle is an associate editor of CJS; she was not involved in the review of this manuscript or in the decision to accept it for publication. A. Seely is the founder and chief science officer of Therapeutic Monitoring Systems, a company dedicated to commercialization of variability-derived clinical decision support tools in the intensive care unit. This work has no relationship to the submitted work. No other competing interests were declared., (© 2019 Joule Inc. or its licensors)
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- 2019
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182. Prenatal maternal biomarkers for the early diagnosis of congenital malformations: A review.
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Wagner R, Tse WH, Gosemann JH, Lacher M, and Keijzer R
- Subjects
- Biomarkers metabolism, Congenital Abnormalities metabolism, Female, Humans, Pregnancy, Body Fluids metabolism, Congenital Abnormalities diagnosis, Prenatal Diagnosis methods
- Abstract
Congenital anomalies cause ~7% of all neonatal deaths, many of which have no identified pathophysiological cause. Because accurate and robust laboratory tests are unavailable for most birth defects, physicians rely on imaging such as ultrasound and MRI. Biomarkers from human body fluids are considered a powerful diagnostic tool to assess human disease and health as it mirrors an individual's condition. Minimally invasive 'liquid biopsies' from blood samples are highly valuable for diagnosis, prognosis, risk assessment, and treatment of many conditions. Recent large-scale analysis ('omics') have enabled researchers to identify novel biomarkers in different areas. To accurately facilitate the early detection of congenital anomalies, the identification of biomarkers from maternal plasma should be promoted. This approach will uncover new opportunities in prenatal diagnosing and likely lead to a better understanding of the pathogenesis of congenital anomalies.
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- 2019
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183. Establishment of a biobank for human lung tissues of congenital diaphragmatic hernia and congenital pulmonary airway malformation.
- Author
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Wagner R, Ayoub L, Kahnamoui S, Li H, Patel D, Liu D, Del Bigio MR, Stefanovici C, Lacher M, and Keijzer R
- Subjects
- Child, Child, Preschool, Female, Gestational Age, Humans, Infant, Infant, Newborn, Male, Retrospective Studies, Cystic Adenomatoid Malformation of Lung, Congenital pathology, Hernias, Diaphragmatic, Congenital pathology, Tissue Banks organization & administration
- Abstract
Background: Human tissue samples are an invaluable and little available source of information for translational studies of congenital lung diseases such as Congenital Diaphragmatic Hernia (CDH) or Congenital Pulmonary Airway Malformation (CPAM)., Purpose: We aimed to establish a human lung tissue biobank of CDH and CPAM patients together with age-matched controls, coupled with a clinical database., Methods: Pathology records from autopsies or surgical specimens for CDH and CPAM cases between 1980 and 2017 were reviewed. For surviving individuals, clinical patient data was obtained from corresponding pediatric surgery reports. Formalin-fixed, paraffin-embedded tissues of patients and age-matched controls were systematically stored for further translational studies. RNA integrity was determined on selected CDH blocks., Results: A total of 16 CDH and 18 CPAM and age-matched control lung tissue blocks were included in our biobank. Ages ranged from 22 to 41 weeks of gestation (GA) in CDH (33.9 ± 6.35 weeks) and 26 weeks (GA) and 12 years in CPAM (2.3 ± 3.7 y). RNA isolation from CDH and control blocks yielded good RNA quality (OD 260/280 ratio: 2.01-2.09, OD 260/230 ratio: 2.04-2.09)., Conclusion: We established a unique human biobank for CDH and CPAM tissues. The combination with clinical patient data will allow us to design future translational studies to improve our understanding of the disease pathogenesis of these congenital malformations., (Copyright © 2019. Published by Elsevier Inc.)
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- 2019
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184. The presence of a hernia sac in isolated congenital diaphragmatic hernia is associated with less disease severity: A retrospective cohort study.
- Author
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Levesque M, Derraugh G, Schantz D, Morris MI, Shawyer A, Lum Min SA, and Keijzer R
- Subjects
- Administration, Inhalation, Child, Female, Free Radical Scavengers administration & dosage, Humans, Infant, Infant, Newborn, Male, Nitric Oxide administration & dosage, Prognosis, Recurrence, Respiration, Artificial, Retrospective Studies, Severity of Illness Index, Hernias, Diaphragmatic, Congenital mortality, Hernias, Diaphragmatic, Congenital pathology, Oxygen Inhalation Therapy
- Abstract
Introduction: We aimed to determine if the presence of a hernia sac in neonates with isolated congenital diaphragmatic hernia (CDH) was associated with better clinical outcomes., Methods: We performed a retrospective cohort study of infants with isolated CDH from 1991 to 2015. Primary outcome measures were oxygen-dependence and mortality at 28 days. Secondary measures were: inhaled nitric oxide use, vasoactive medication use, ventilator support, and recurrence rates., Results: Seventy-one patients met the inclusion criteria: 14 patients (19.7%) had a hernia sac, and 57 patients (80.3%) did not. Mortality did not differ between the 2 groups [0 of 14 versus 3 of 57 (5.3%) (p = 1.000)]. Hernia sac patients had similar oxygen-dependence after 28 days [1 of 14 (7.1%) versus 14 of 57 (24.6%) (p = 0.273)]. Hernia sac children required less iNO (0.64 ± 2.41 vs. 6.35 ± 12.2 days, p = 0.002), vasoactive medications (2.79 ± 3.07 vs. 5.36 ± 5.52, p = 0.027), and time on ventilation (7.62 ± 6.12 vs. 15.9 ± 19.2, p = 0.010). Hernia sac children had similar recurrence rates within 2 years [0 of 14 versus 7 of 57 (12.3%) (p = 0.331)]., Conclusion: The presence of a hernia sac was not associated with lower rates of oxygen dependency or death at 28 days but was associated with decreased inhaled nitric oxide, vasoactive medication, and ventilator use., Level of Evidence: III., (Copyright © 2019 Elsevier Inc. All rights reserved.)
- Published
- 2019
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185. Prenatal microRNA miR-200b Therapy Improves Nitrofen-induced Pulmonary Hypoplasia Associated With Congenital Diaphragmatic Hernia.
- Author
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Khoshgoo N, Kholdebarin R, Pereira-Terra P, Mahood TH, Falk L, Day CA, Iwasiow BM, Zhu F, Mulhall D, Fraser C, Correia-Pinto J, and Keijzer R
- Subjects
- 2,4-Dinitrophenol administration & dosage, Abnormalities, Multiple genetics, Animals, Disease Models, Animal, Hernias, Diaphragmatic, Congenital chemically induced, Hernias, Diaphragmatic, Congenital complications, Hernias, Diaphragmatic, Congenital genetics, Lung Diseases complications, Lung Diseases genetics, Rats, Rats, Sprague-Dawley, Abnormalities, Multiple therapy, Fetal Therapies methods, Hernias, Diaphragmatic, Congenital therapy, Lung abnormalities, Lung Diseases therapy, MicroRNAs therapeutic use
- Abstract
Objective: We aimed to evaluate the use of miR-200b as a prenatal transplacental therapy in the nitrofen rat model of abnormal lung development and congenital diaphragmatic hernia (CDH)., Background: Pulmonary hypoplasia (PH) and pulmonary hypertension determine mortality and morbidity in CDH babies. There is no safe medical prenatal treatment available. We previously discovered that higher miR-200b is associated with better survival in CDH babies. Here, we investigate the role of miR-200b in the nitrofen rat model of PH and CDH and evaluate its use as an in vivo prenatal therapy., Methods: We profiled miR-200b expression during nitrofen-induced PH using RT-qPCR and in situ hybridization in the nitrofen rat model of PH and CDH. The effects of nitrofen on downstream miR-200b targets were studied in bronchial lung epithelial cells using a SMAD luciferase assay, Western blotting and Immunohistochemistry. We evaluated miR-200b as a lung growth promoting therapy ex vivo and in vivo using lung explant culture and transplacental prenatal therapy in the nitrofen rat model., Results: We show that late lung hypoplasia in CDH is associated with (compensatory) upregulation of miR-200b in less hypoplastic lungs. Increasing miR-200b abundance with mimics early after nitrofen treatment decreases SMAD-driven TGF-β signaling and rescues lung hypoplasia both in vitro and in vivo. Also, prenatal miR-200b therapy decreases the observed incidence of CDH., Conclusions: Our data indicate that miR-200b improves PH and decreases the incidence of CDH. Future studies will further exploit this newly discovered prenatal therapy for lung hypoplasia and CDH.
- Published
- 2019
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186. Introduction.
- Author
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Dakshinamurti S, Dolinsky V, Keijzer R, and Olson D
- Published
- 2019
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187. Identifying Information Needs for Hirschsprung Disease Through Caregiver Involvement via Social Media: A Prioritization Study and Literature Review.
- Author
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Wittmeier KD, Hobbs-Murison K, Holland C, Crawford E, Loewen H, Morris M, Lum Min S, Abou-Setta A, and Keijzer R
- Subjects
- Child, Child, Preschool, Health Resources, Humans, Infant, Infant, Newborn, Retrospective Studies, Surveys and Questionnaires, Caregivers psychology, Hirschsprung Disease therapy, Medical Informatics trends, Social Media trends
- Abstract
Background: Patient and public involvement in health research is important to produce relevant and impactful results., Objective: This paper aimed to prioritize and summarize Hirschsprung disease (HD)-related information needs among caregivers of children with HD and pediatric surgeons through partnership with a parent-initiated social media campaign., Methods: We conducted a Web-based survey with the 2 stakeholder groups to identify information needs. The caregiver survey was conducted through a global Web-based community, and the surgeon survey was distributed to members of the Canadian Association of Paediatric Surgeons (CAPS). We conducted a literature review to identify evidence on the prioritized topics., Results: Our findings showed that 54.9% (89/162) of the individuals completed the caregiver survey and 23.8% (52/218 listed members) of the pediatric surgeons completed the survey distributed through CAPS. Only 20% (18/89) of the caregivers reported being very satisfied or satisfied with the current HD-related resources. A final prioritized list of information needs included bowel management, nutrition and growth, infection, perianal irritation, gastrointestinal pain, surgical diagnostics, and surgical complications. In total, 87 studies were included in the literature review, which included the following: 8 reviews, 2 randomized controlled trials, 74 cohort studies, and 3 practice guidelines. Two priority issues identified by caregivers had only a single study that met the inclusion criteria, whereas 1 topic had none., Conclusions: With caregiver and surgeon input, we identified 7 information priority areas related to HD. A review of the literature on the priorities found little evidence to support the development of high-quality guidelines. More research is necessary to meet the information needs related to HD as identified by stakeholders., (©Kristy DM Wittmeier, Kendall Hobbs-Murison, Cindy Holland, Elizabeth Crawford, Hal Loewen, Melanie Morris, Suyin Lum Min, Ahmed Abou-Setta, Richard Keijzer. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 21.12.2018.)
- Published
- 2018
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188. Myocardin regulates mitochondrial calcium homeostasis and prevents permeability transition.
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Mughal W, Martens M, Field J, Chapman D, Huang J, Rattan S, Hai Y, Cheung KG, Kereliuk S, West AR, Cole LK, Hatch GM, Diehl-Jones W, Keijzer R, Dolinsky VW, Dixon IM, Parmacek MS, and Gordon JW
- Subjects
- Animals, Cells, Cultured, Doxorubicin pharmacology, Gene Expression drug effects, Heart drug effects, Isoproterenol pharmacology, Membrane Potential, Mitochondrial drug effects, Membrane Proteins antagonists & inhibitors, Membrane Proteins genetics, Membrane Proteins metabolism, Mice, Mice, Inbred C57BL, MicroRNAs metabolism, Myocytes, Cardiac cytology, Myocytes, Cardiac metabolism, Nuclear Proteins antagonists & inhibitors, Nuclear Proteins genetics, Permeability drug effects, Proto-Oncogene Proteins antagonists & inhibitors, Proto-Oncogene Proteins genetics, Proto-Oncogene Proteins metabolism, RNA Interference, RNA, Small Interfering metabolism, Rats, Sarcoplasmic Reticulum metabolism, Trans-Activators antagonists & inhibitors, Trans-Activators genetics, Calcium metabolism, Mitochondria metabolism, Nuclear Proteins metabolism, Trans-Activators metabolism
- Abstract
Myocardin is a transcriptional co-activator required for cardiovascular development, but also promotes cardiomyocyte survival through an unclear molecular mechanism. Mitochondrial permeability transition is implicated in necrosis, while pore closure is required for mitochondrial maturation during cardiac development. We show that loss of myocardin function leads to subendocardial necrosis at E9.5, concurrent with elevated expression of the death gene Nix. Mechanistically, we demonstrate that myocardin knockdown reduces microRNA-133a levels to allow Nix accumulation, leading to mitochondrial permeability transition, reduced mitochondrial respiration, and necrosis. Myocardin knockdown elicits calcium release from the endo/sarcoplasmic reticulum with mitochondrial calcium accumulation, while restoration of microRNA-133a function, or knockdown of Nix rescues calcium perturbations. We observed reduced myocardin and elevated Nix expression within the infarct border-zone following coronary ligation. These findings identify a myocardin-regulated pathway that maintains calcium homeostasis and mitochondrial function during development, and is attenuated during ischemic heart disease. Given the diverse role of Nix and microRNA-133a, these findings may have broader implications to metabolic disease and cancer.
- Published
- 2018
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189. MicroRNA 200b is upregulated in the lungs of fetal rabbits with surgically induced diaphragmatic hernia.
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Eastwood MP, Deprest J, Russo FM, Wang H, Mulhall D, Iwasiow B, Mahood TH, and Keijzer R
- Subjects
- Animals, Disease Models, Animal, Female, Fetal Weight, Gestational Age, Hernias, Diaphragmatic, Congenital etiology, In Situ Hybridization veterinary, Lung metabolism, MicroRNAs genetics, Organ Size, Pregnancy, Rabbits, Real-Time Polymerase Chain Reaction veterinary, Trachea surgery, Up-Regulation, Hernias, Diaphragmatic, Congenital metabolism, Lung chemistry, Lung embryology, MicroRNAs analysis
- Abstract
Objective: Profiling of miR-200b expression and its targets (transforming growth factor [TGF]-β2 and ZEB2) in the surgical rabbit congenital diaphragmatic hernia (DH) model before and after tracheal occlusion (TO)., Methods: Thirty-eight timed-pregnant rabbits had left DH creation on gestational day (GD) 23. On GD28, 17 randomly selected fetuses had TO. We harvested fetuses at GD23, GD28, or GD30. We calculated lung-to-body weight ratios, processed lungs for miR-200b in situ hybridization and real-time quantitative polymerase chain reaction, and evaluated effects on downstream targets TGF-β2 or ZEB2., Results: We obtained 16 DH fetuses (n = 7 GD28 and n = 9 GD30), 13 TO fetuses (GD30), and 38 control fetuses (n = 15 GD23, n = 11 GD28, and n = 12 GD30). Diaphragmatic hernia lungs were hypoplastic, and TO resulted in control lung-to-body weight ratio levels. Term miR-200b-3p levels were significantly upregulated in the hypoplastic compared with control ipsilateral lung (1.906 ± 0.90 vs 0.7429 ± 0.44) (P < .01). Fetal TO ipsilateral lungs displayed a variable miR-200b response on in situ hybridization and polymerase chain reaction, with levels similar to control and congenital DH lungs. The TGF-β2 was unchanged in hypoplastic and TO lungs, and ZEB2 tended to be reduced in TO compared with DH lungs (1.79 [0.4-2.9] vs 0.73 [0.5-1.4])., Conclusions: Hypoplastic fetal rabbit lungs display upregulation of miR-200b expression although downstream targets are not different from controls. Following TO, fetal rabbit lungs display a variable miR-200b response., (© 2018 John Wiley & Sons, Ltd.)
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- 2018
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190. Antenatal management of congenital diaphragmatic hernia today and tomorrow.
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van der Veeken L, Russo FM, van der Merwe J, Basurto D, Sharma D, Nguyen T, Eastwood MP, Khoshgoo N, Toelen J, Allegaert K, Dekoninck P, Hooper SB, Keijzer R, De Coppi P, and Deprest J
- Subjects
- Female, Hernias, Diaphragmatic, Congenital complications, Humans, Hypertension, Pulmonary etiology, Hypertension, Pulmonary prevention & control, Phosphodiesterase 5 Inhibitors administration & dosage, Pregnancy, Prognosis, Sildenafil Citrate administration & dosage, Fetal Therapies methods, Fetoscopy methods, Hernias, Diaphragmatic, Congenital therapy
- Abstract
Congenital diaphragmatic hernia is rare birth defect, which can be easily corrected after birth. The main problem is that herniation of viscera during fetal life impairs lung development, leading to a 30% mortality and significant morbidity. In isolated cases the outcome can be accurately predicted prenatally by medical imaging. Cases with a poor prognosis can be treated before birth; clinically this is by fetoscopic endoluminal tracheal occlusion. Obstruction of the airways triggers lung growth. This procedure is currently being evaluated in a global clinical trial for left sided cases; right sided cases with poor prognosis are offered the procedure clinically. The search for more potent and less invasive therapies continues. Prenatal transplacental sildenafil administration will in due course be tried clinically, with the aim to reduce the occurrence of persistent pulmonary hypertension, either alone or in combination with fetal surgery. Other medical approaches are in an earlier translational phase.
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- 2018
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191. Diagnosis and management of congenital diaphragmatic hernia: a clinical practice guideline.
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Puligandla PS, Skarsgard ED, Offringa M, Adatia I, Baird R, Bailey M, Brindle M, Chiu P, Cogswell A, Dakshinamurti S, Flageole H, Keijzer R, McMillan D, Oluyomi-Obi T, Pennaforte T, Perreault T, Piedboeuf B, Riley SP, Ryan G, Synnes A, and Traynor M
- Subjects
- Canada, Echocardiography, Female, Humans, Infant, Infant, Newborn, Patient Care Team, Pregnancy, Prenatal Diagnosis, Societies, Medical, Ultrasonography, Prenatal, Hernias, Diaphragmatic, Congenital diagnostic imaging, Hernias, Diaphragmatic, Congenital therapy, Hypertension, Pulmonary diagnostic imaging
- Abstract
Competing Interests: Competing interests: Pramod Puligandla received a one-time honorarium, outside the submitted work, for participation in a meeting regarding the use of inhaled nitric oxide in adults and children hosted by Ikaria Canada Inc. Ian Adatia reports a forthcoming grant award from Malinkcrodt. No other competing interests were declared.
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- 2018
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192. Living Like an Academic Athlete: How to Improve Clinical and Academic Productivity as a Gastroenterologist.
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Benchimol EI and Keijzer R
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- Academic Medical Centers, Faculty, Medical, Humans, Efficiency, Gastroenterology, Time Management
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- 2018
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193. MicroRNA-200b regulates distal airway development by maintaining epithelial integrity.
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Khoshgoo N, Visser R, Falk L, Day CA, Ameis D, Iwasiow BM, Zhu F, Öztürk A, Basu S, Pind M, Fresnosa A, Jackson M, Siragam VK, Stelmack G, Hicks GG, Halayko AJ, and Keijzer R
- Subjects
- Animals, Epithelial Cells pathology, Gene Expression Profiling methods, Gene Expression Regulation, Developmental, Gene Knockout Techniques, Gene Ontology, Gene Regulatory Networks, Hernias, Diaphragmatic, Congenital genetics, Hernias, Diaphragmatic, Congenital physiopathology, Humans, Lung cytology, Lung physiopathology, Mice, Respiratory Function Tests, Sequence Analysis, RNA, Epithelial Cells cytology, Lung growth & development, MicroRNAs genetics, Up-Regulation
- Abstract
miR-200b plays a role in epithelial-to-mesenchymal transition (EMT) in cancer. We recently reported abnormal expression of miR-200b in the context of human pulmonary hypoplasia in congenital diaphragmatic hernia (CDH). Smaller lung size, a lower number of airway generations, and a thicker mesenchyme characterize pulmonary hypoplasia in CDH. The aim of this study was to define the role of miR-200b during lung development. Here we show that miR-200b
-/- mice have abnormal lung function due to dysfunctional surfactant, increased fibroblast-like cells and thicker mesenchyme in between the alveolar walls. We profiled the lung transcriptome in miR-200b-/- mice, and, using Gene Ontology analysis, we determined that the most affected biological processes include cell cycle, apoptosis and protein transport. Our results demonstrate that miR-200b regulates distal airway development through maintaining an epithelial cell phenotype. The lung abnormalities observed in miR-200b-/- mice recapitulate lung hypoplasia in CDH.- Published
- 2017
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194. Lung size and liver herniation predict need for extracorporeal membrane oxygenation but not pulmonary hypertension in isolated congenital diaphragmatic hernia: systematic review and meta-analysis.
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Russo FM, Eastwood MP, Keijzer R, Al-Maary J, Toelen J, Van Mieghem T, and Deprest JA
- Subjects
- Extracorporeal Membrane Oxygenation, Female, Hernias, Diaphragmatic, Congenital complications, Hernias, Diaphragmatic, Congenital diagnostic imaging, Hernias, Diaphragmatic, Congenital therapy, Humans, Liver Diseases congenital, Predictive Value of Tests, Pregnancy, Severity of Illness Index, Ultrasonography, Prenatal, Hernias, Diaphragmatic, Congenital physiopathology, Liver Diseases complications, Lung pathology
- Abstract
Objectives: To identify antenatal predictors of persistent pulmonary hypertension (PPH) and the need for extracorporeal membrane oxygenation (ECMO) in fetuses with congenital diaphragmatic hernia (CDH)., Methods: We performed a systematic literature review on antenatal diagnostic tests in fetuses with isolated CDH. The primary outcomes assessed were PPH within 28 days of age and the need for ECMO. Quality of studies was assessed with the QUADAS-2 tool. Meta-analysis was performed when at least three studies reported on the same test. Sensitivity analysis was performed according to prenatal management of CDH (tracheal occlusion vs expectant management)., Results: Thirty-eight studies met the inclusion criteria. Fifteen reported on the incidence of PPH only, 19 on the need for ECMO only and four reported on both outcomes. The general quality of the studies was moderate; most studies were retrospective (61%) and single-center series (92%). One study included only fetuses undergoing tracheal occlusion, 22 included only fetuses managed expectantly in utero and 15 included both populations. We could not identify antenatal predictors of PPH. The need for ECMO was predicted by parameters indicative of lung size: lung-to-head ratio (LHR) (relative risk (RR) for LHR < 1, 1.65 (95% CI, 1.27-2.14)) and observed/expected LHR (standardized mean difference (SMD), -0.70 (95% CI, -0.98 to -0.42)) measured by ultrasound and observed/expected total lung volume (SMD, -1.00 (95% CI, -1.52 to -0.48)) measured by magnetic resonance imaging. Liver herniation was also associated with an increased risk of need for ECMO (RR, 3.04 (95% CI, 2.23-4.14)). These results were confirmed by a sensitivity analysis of studies that included only expectantly managed cases. Data on vascular assessment for the prediction of PPH could not be pooled as most of the parameters were evaluated in a single series or in different series by the same principal investigator., Conclusions: In fetuses with CDH, lung size and liver herniation predict the need for ECMO, however a predictor for PPH is still lacking. Further studies aimed at diagnosing impaired vascular development in utero should therefore be undertaken. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd., (Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.)
- Published
- 2017
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195. Abnormal lung development in congenital diaphragmatic hernia.
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Ameis D, Khoshgoo N, and Keijzer R
- Subjects
- Diaphragm abnormalities, Diaphragm embryology, Genetic Markers, Genetic Predisposition to Disease, Hernias, Diaphragmatic, Congenital genetics, Hernias, Diaphragmatic, Congenital pathology, Humans, Lung abnormalities, Hernias, Diaphragmatic, Congenital embryology, Lung embryology
- Abstract
The outcomes of patients diagnosed with congenital diaphragmatic hernia (CDH) have recently improved. However, mortality and morbidity remain high, and this is primarily caused by the abnormal lung development resulting in pulmonary hypoplasia and persistent pulmonary hypertension. The pathogenesis of CDH is poorly understood, despite the identification of certain candidate genes disrupting normal diaphragm and lung morphogenesis in animal models of CDH. Defects within the lung mesenchyme and interstitium contribute to disturbed distal lung development. Frequently, a disturbance in the development of the pleuroperitoneal folds (PPFs) leads to the incomplete formation of the diaphragm and subsequent herniation. Most candidate genes identified in animal models have so far revealed relatively few strong associations in human CDH cases. CDH is likely a highly polygenic disease, and future studies will need to reconcile how disturbances in the expression of multiple genes cause the disease. Herein, we summarize the available literature on abnormal lung development associated with CDH., (Copyright © 2017 Elsevier Inc. All rights reserved.)
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- 2017
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196. Appendectomy versus non-operative treatment for acute uncomplicated appendicitis in children: study protocol for a multicentre, open-label, non-inferiority, randomised controlled trial.
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Hall NJ, Eaton S, Abbo O, Arnaud AP, Beaudin M, Brindle M, Bütter A, Davies D, Jancelewicz T, Johnson K, Keijzer R, Lapidus-Krol E, Offringa M, Piché N, Rintala R, Skarsgard E, Svensson JF, Ungar WJ, Wester T, Willan AR, Zani A, St Peter SD, and Pierro A
- Abstract
Background: Appendectomy is considered the gold standard treatment for acute appendicitis. Recently the need for surgery has been challenged in both adults and children. In children there is growing clinician, patient and parental interest in non-operative treatment of acute appendicitis with antibiotics as opposed to surgery. To date no multicentre randomised controlled trials that are appropriately powered to determine efficacy of non-operative treatment (antibiotics) for acute appendicitis in children compared with surgery (appendectomy) have been performed., Methods: Multicentre, international, randomised controlled trial with a non-inferiority design. Children (age 5-16 years) with a clinical and/or radiological diagnosis of acute uncomplicated appendicitis will be randomised (1:1 ratio) to receive either laparoscopic appendectomy or treatment with intravenous (minimum 12 hours) followed by oral antibiotics (total course 10 days). Allocation to groups will be stratified by gender, duration of symptoms (> or <48 hours) and centre. Children in both treatment groups will follow a standardised treatment pathway. Primary outcome is treatment failure defined as additional intervention related to appendicitis requiring general anaesthesia within 1 year of randomisation (including recurrent appendicitis) or negative appendectomy. Important secondary outcomes will be reported and a cost-effectiveness analysis will be performed. The primary outcome will be analysed on a non-inferiority basis using a 20% non-inferiority margin. Planned sample size is 978 children., Discussion: The APPY trial will be the first multicentre randomised trial comparing non-operative treatment with appendectomy for acute uncomplicated appendicitis in children. The results of this trial have the potential to revolutionise the treatment of this common gastrointestinal emergency. The randomised design will limit the effect of bias on outcomes seen in other studies., Trial Registration Number: clinicaltrials.gov: NCT02687464. Registered on Jan 13th 2016., Competing Interests: Competing interests: None declared.
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- 2017
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197. Applying vacuum to accomplish reduced wound infections in laparoscopic pediatric surgery.
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Visser R, Milbrandt K, Lum Min S, Wiseman N, Hancock BJ, Morris M, and Keijzer R
- Subjects
- Adolescent, Child, Child, Preschool, Female, Humans, Infant, Infant, Newborn, Male, Pediatrics, Single-Blind Method, Specialties, Surgical, Surgical Wound Infection epidemiology, Treatment Outcome, Laparoscopy, Negative-Pressure Wound Therapy, Postoperative Care methods, Surgical Wound Infection prevention & control
- Abstract
Introduction: The prevention of surgical site infections has received little attention in pediatric surgery. Negative pressure wound therapy is used to treat complex wounds. We hypothesized that this principle could reduce wound infection rates following laparoscopic surgery. We tested this in a randomized controlled trial., Materials and Methods: We randomized pediatric patients with an umbilical port site to a standard dressing or a vacuum dressing. The dressings were removed 48h after surgery. A nurse blinded for the treatment inspected the umbilical wound between post-operative days 7-10 for infection. Data comparison was performed using a Fisher exact test with p<0.05 defined as significant., Results: We recruited 90 patients over 2 years and randomized 44 to the vacuum dressing arm and 42 to the control arm. We observed a 2.8% (n=1/35) infection rate in the vacuum dressing group and 3.3% (n=1/30) in the control group (p=1.0)., Discussion: We ended our study early when an interim analysis showed an impractical number of patients would be required to achieve sufficient power. We did not find a significant difference between the control and vacuum dressings in reducing post-operative wound infections., Level of Evidence: 3., (Copyright © 2017 Elsevier Inc. All rights reserved.)
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- 2017
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198. MicroRNAs in Lung Development and Disease.
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Ameis D, Khoshgoo N, Iwasiow BM, Snarr P, and Keijzer R
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- Animals, Asthma genetics, Bronchopulmonary Dysplasia genetics, Cystic Fibrosis genetics, Gene Expression, Gene Expression Regulation, Developmental, Humans, Lung growth & development, Lung embryology, Lung Diseases genetics, MicroRNAs genetics
- Abstract
MicroRNAs (miRNAs) are small (∼22 nucleotides), non-coding RNA molecules that regulate gene expression post-transcriptionally by inhibiting target mRNAs. Research into the roles of miRNAs in lung development and disease is at the early stages. In this review, we discuss the role of miRNAs in pediatric respiratory disease, including cystic fibrosis, asthma, and bronchopulmonary dysplasia., (Copyright © 2016. Published by Elsevier Ltd.)
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- 2017
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199. Fetal Tracheal Occlusion for Severe Pulmonary Hypoplasia in Isolated Congenital Diaphragmatic Hernia: A Systematic Review and Meta-analysis of Survival.
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Al-Maary J, Eastwood MP, Russo FM, Deprest JA, and Keijzer R
- Subjects
- Female, Humans, Pregnancy, Survival Analysis, Fetoscopy methods, Hernias, Diaphragmatic, Congenital mortality, Hernias, Diaphragmatic, Congenital surgery, Lung abnormalities, Trachea surgery
- Abstract
Objective: To evaluate fetal survival after tracheal occlusion in fetuses with severe pulmonary hypoplasia and isolated congenital diaphragmatic hernia (CDH)., Background: Despite recent advances in neonatal intensive care, CDH still has a high mortality and morbidity. Fetoscopic endoluminal tracheal occlusion (FETO) stimulates lung growth and improves gas exchange in animal models of CDH, but the effects in humans are still under investigation., Methods: We searched Pubmed, Cochrane, EMBASE, and Scopus databases for clinical studies on tracheal occlusion and CDH. All studies comparing FETO and a contemporary control group were included. The primary outcome was survival, with the need for oxygen on discharge the secondary outcome. Meta-analysis of outcome measures was performed and odds ratios, relative risk ratios, and 95% confidence intervals were estimated with a fixed-effects model and were reported in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidance., Results: Between 1997 and 2015, five eligible studies describing 211 patients were included (101 control and 110 FETO). All studies selected isolated severe CDH fetuses with a lung-to-head ratio 1.0 or less and liver herniation into the thoracic cavity. FETO favored survival outcome (odds ratio 13.32; 95% confidence interval, 5.40-32.87). Meta-analysis of the secondary outcome oxygen need at discharge could not be calculated, because it was not reported in all included studies., Conclusions: FETO improves survival in isolated CDH with severe pulmonary hypoplasia compared with the standard perinatal management.
- Published
- 2016
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200. The transcriptome of nitrofen-induced pulmonary hypoplasia in the rat model of congenital diaphragmatic hernia.
- Author
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Mahood TH, Johar DR, Iwasiow BM, Xu W, and Keijzer R
- Subjects
- Animals, Female, Gene Expression Regulation, Developmental, Hernias, Diaphragmatic, Congenital pathology, Humans, Lung drug effects, Lung embryology, MicroRNAs metabolism, Phenyl Ethers adverse effects, Phosphatidylinositol 3-Kinases metabolism, Polymerase Chain Reaction, RNA, Messenger metabolism, Rats, Sequence Analysis, DNA, Signal Transduction genetics, Transforming Growth Factor beta metabolism, Hernias, Diaphragmatic, Congenital metabolism, Lung pathology, Transcriptome
- Abstract
Background: We currently do not know how the herbicide nitrofen induces lung hypoplasia and congenital diaphragmatic hernia in rats. Our aim was to compare the differentially expressed transcriptome of nitrofen-induced hypoplastic lungs to control lungs in embryonic day 13 rat embryos before the development of embryonic diaphragmatic defects., Methods: Using next-generation sequencing technology, we identified the expression profile of microRNA (miRNA) and mRNA genes. Once the dataset was validated by both RT-qPCR and digital-PCR, we conducted gene ontology, miRNA target analysis, and orthologous miRNA sequence matching for the deregulated miRNAs in silico., Results: Our study identified 186 known mRNA and 100 miRNAs which were differentially expressed in nitrofen-induced hypoplastic lungs. Sixty-four rat miRNAs homologous to known human miRNAs were identified. A subset of these genes may promote lung hypoplasia in rat and/or human, and we discuss their associations. Potential miRNA pathways relevant to nitrofen-induced lung hypoplasia include PI3K, TGF-β, and cell cycle kinases., Conclusion: Nitrofen-induced hypoplastic lungs have an abnormal transcriptome that may lead to impaired development.
- Published
- 2016
- Full Text
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