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Lung infections are one of the leading causes of death worldwide, and this situation has been exacerbated by the emergence of COVID-19. Pre-clinical modelling of viral infections has relied on cell cultures that lack 3D structure and the context of lung extracellular matrices. Here, we propose a bioreactor-based, whole-organ lung model of viral infection. The bioreactor takes advantage of an automated system to achieve efficient decellularization of a whole rat lung, and recellularization of the scaffold using primary human bronchial cells. Automatization allowed for the dynamic culture of airway epithelial cells in a breathing-mimicking setup that led to an even distribution of lung epithelial cells throughout the distal regions. In the sealed bioreactor system, we demonstrate proof-of-concept for viral infection with the engineered lung by infecting primary human airway epithelial cells. Moreover, to assess the possibility of drug screening in this model, we demonstrate the efficacy of the broad-spectrum antiviral Remdesivir. This whole-organ scale lung infection model represents a step towards modelling viral infection of human cells in a 3D context, providing a powerful tool to investigate the mechanisms of the early stages of pathogenic infections and the development of effective treatment strategies for respiratory diseases.

PurposeThis paper aims to build upon previous work to definitively establish in vitro models of murine pseudoglandular stage lung development. These can be easily translated to human fetal lung samples to allow the investigation of lung development in physiologic and pathologic conditions.MethodsLungs were harvested from mouse embryos at E12.5 and cultured in three different settings, i.e., whole lung culture, mesenchyme-free epithelium culture, and organoid culture. For the whole lung culture, extracted lungs were embedded in Matrigel and incubated on permeable filters. Separately, distal epithelial tips were isolated by firstly removing mesothelial and mesenchymal cells, and then severing the tips from the airway tubes. These were then cultured either in branch-promoting or self-renewing conditions.ResultsCultured whole lungs underwent branching morphogenesis similarly to native lungs. Real-time qPCR analysis demonstrated expression of key genes essential for lung bud formation. The culture condition for epithelial tips was optimized by testing different concentrations of FGF10 and CHIR99021 and evaluating branching formation. The epithelial rudiments in self-renewing conditions formed spherical 3D structures with homogeneous Sox9 expression.ConclusionWe report efficient protocols for ex vivo culture systems of pseudoglandular stage mouse embryonic lungs. These models can be applied to human samples and could be useful to paediatric surgeons to investigate normal lung development, understand the pathogenesis of congenital lung diseases, and explore novel therapeutic strategies.

Anorectal malformations (ARM) represent a broad spectrum of patients with different level of the rectum and type of a fistula. Standardized approaches are usually successful, but patients occasionally present with an unusual course of fistula which requires a modified surgical strategy. We present here three male ARM patients with an atypical fistula which did not have connection with the urinary tract, but ran near the fistula. Case 1 has a low-type ARM with a rectoscrotal fistula running deep and partly involved in the corpus spongiosum. Anorectoplasty was performed through an anterior sagittal incision and the anterior wall of the fistula was laid open leaving the posterior wall undetached. Case 2 was diagnosed with an intermediate-type ARM with a long rectoscrotal fistula running near and parallel the urethra. Posterior sagittal anorectoplasty (PSARP) was performed leaving the fistula untouched. Case 3 presented with an intermediate-type ARM with a rectoperineal fistula adherent to the urethra. The patient was treated by PSARP leaving the fistula and part of the muscle coat of the rectum in situ. All the cases were smoothly discharged and no urological complication nor problem associated with the residual fistula was observed at the latest follow-up (17 months-2 years). Preoperative distal colostography with the aid of diverting colostomy was importantly useful for deciding surgical procedure.

A 16-month-old boy was referred to our hospital for the management of suspected lithium button battery (LBB) ingestion. He had been previously well, but became febrile with a persistent cough resistant to oral antibiotics and dysphagia for 5 days. Radiography identified an LBB lodged in the upper esophagus. The LBB was retrieved under direct visualization with rigid laryngoscopy. He was sedated for 5 days and enteral feeding was commenced through a nasojejunal tube on the next day after procedure. On day 8 after retrieval, endoscopy and fluoroscopy identified a tracheoesophageal fistula (TEF), 6 mm in diameter. Conservative management was conducted with periodic follow-up endoscopies, which showed signs of healing in the esophagus. Following continuous antibiotics and proactive nutritional support, the TEF was found to have closed spontaneously by day 28 after the LBB removal. We present our experience of the successful nonsurgical management of acquired TEF secondary to LBB ingestion and aim to establish a protocol for managing it conservatively by reviewing the relevant literature.

BACKGROUND: Pregnant women have been identified as a potentially at-risk group concerning COVID-19 infection, but little is known regarding the susceptibility of the fetus to infection. Co-expression of ACE2 and TMPRSS2 has been identified as a prerequisite for infection, and expression across different tissues is known to vary between children and adults. However, the expression of these proteins in the fetus is unknown. METHODS: We performed a retrospective analysis of a single cell data repository. The data were then validated at both gene and protein level by performing RT-qPCR and two-colour immunohistochemistry on a library of second-trimester human fetal tissues. FINDINGS: TMPRSS2 is present at both gene and protein level in the predominantly epithelial fetal tissues analysed. ACE2 is present at significant levels only in the fetal intestine and kidney, and is not expressed in the fetal lung. The placenta also does not co-express the two proteins across the second trimester or at term. INTERPRETATION: This dataset indicates that the lungs are unlikely to be a viable route of SARS-CoV2 fetal infection. The fetal kidney, despite presenting both the proteins required for the infection, is anatomically protected from the exposure to the virus. However, the gastrointestinal tract is likely to be susceptible to infection due to its high co-expression of both proteins, as well as its exposure to potentially infected amniotic fluid. TWEETABLE ABSTRACT: This work provides detailed mechanistic insight into the relative protection & vulnerabilities of the fetus & placenta to SARS-CoV-2 infection by scRNAseq & protein expression analysis for ACE2 & TMPRSS2. The findings help to explain the low rate of vertical transmission. ispartof: BJOG vol:129 issue:2 pages:256-266 ispartof: location:England status: published

Tissue architecture is a driving force for morphogenetic processes during development as well as for several physiological and regenerative responses. Far from being a passive static environment, tissue architecture is highly dynamic. Hydrogel technology reproduces in vitro geometrical and mechanical constrains that control the three-dimensional self-organization of (3D) organoids and organ-like cultures. This control is restricted to the initial culture conditions and cannot be adapted to the dynamic morphological changes of complex 3D cultures during their developmental trajectory. Here, we developed a method that overcomes this spatiotemporal limit. Using 2P crosslinking approach, high resolution 3D hydrogel structures can be fabricated within pre-existing hydrogel with spatiotemporal (four-dimensional, 4D) control relative to ex-vivo organotypic or organoid culture. This hydrogel-in-hydrogel bioprinting approach enables to continuously instruct the self-organization of the evolving 3D organ-like cultures.

Tissue engineering (TE) aims to generate bioengineered constructs which can offer a surgical treatment for many conditions involving tissue or organ loss. Construct generation must be guided by suitable assessment tools. However, most current tools (e.g. histology) are destructive, which restricts evaluation to a single-2D anatomical plane, and has no potential for assessing constructs prior to or following their implantation. An alternative can be provided by laboratory-based x-ray phase contrast computed tomography (PC-CT), which enables the extraction of 3D density maps of an organ's anatomy. In this work, we developed a semi-automated image processing pipeline dedicated to the analysis of PC-CT slices of oesophageal constructs. Visual and quantitative (density and morphological) information is extracted on a volumetric basis, enabling a comprehensive evaluation of the regenerated constructs. We believe the presented tools can enable the successful regeneration of patient-specific oesophagus, and bring comparable benefit to a wide range of TE applications. STATEMENT OF SIGNIFICANCE: Phase contrast computed tomography (PC-CT) is an imaging modality which generates high resolution volumetric density maps of biological tissue. In this work, we demonstrate the use of PC-CT as a new tool for guiding the progression of an oesophageal tissue engineering (TE) protocol. Specifically, we developed a semi-automated image-processing pipeline which analyses the oesophageal PC-CT slices, extracting visual and quantitative (density and morphological) information. This information was proven key for performing a comprehensive evaluation of the regenerated constructs, and cannot be obtained through existing assessment tools primarily due to their destructive nature (e.g. histology). This work paves the way for using PC-CT in a wide range of TE applications which can be pivotal for unlocking the potential of this field.

Background CDH UK is a registered charity governed by a volunteer committee and providing informal support to patients, families and healthcare workers affected directly or indirectly with congenital diaphragmatic hernia (CDH) internationally. This is the first patient-led survey undertaken by CDH UK aiming for highlighting the feeding problems and their impact on the daily life of CDH survivors. Methods Answers from CDH survivors were collected through an online questionnaire (SurveyMonkey®) undertaken by CDH UK. The questionnaire contained questions about their feeding problems and support they were receiving for it. Main results Overall, 151 patients answered some parts of the survey and 102 patients completed the questionnaire. Overall, 116 (76.8%) responders reported suffering from any type of feeding issue. Gastric acid reflux (GER) and growth retardation were the commonest symptoms experienced by 97 (91.5%) and 72 (62.2%) responders, respectively. Only 18 (17.0%) responders have received any written information on feeding or details of patient/parent support. Eighty (75.5%) responders are satisfied with the level of support they are receiving, but 78 (76.4%) answered that the whole experience associated with the disease has been very or extremely stressful. Conclusions CDH survivors frequently have various issues with feeding, which may not be adequately supported or discussed clinically. It is desirable to assist the patients to reliable resources of long-term support, including multidisciplinary team (MDT) approach.

While a substantial proportion of adults infected with SARS-CoV-2 progress to develop severe disease, children rarely manifest respiratory complications. Therefore, understanding differences in the local and systemic response to SARS-CoV-2 infection between children and adults may provide important clues about the pathogenesis of SARS-CoV-2 infection. To address this, we first generated a healthy reference multi-omics single cell data set from children (n=30) in whom we have profiled triple matched samples: nasal and tracheal brushings and PBMCs, where we track the developmental changes for 42 airway and 31 blood cell populations from infancy, through childhood to adolescence. This has revealed the presence of naive B and T lymphocytes in neonates and infants with a unique gene expression signature bearing hallmarks of innate immunity. We then contrast the healthy reference with equivalent data from severe paediatric and adult COVID-19 patients (total n=27), from the same three types of samples: upper and lower airways and blood. We found striking differences: children with COVID-19 as opposed to adults had a higher proportion of innate lymphoid and non-clonally expanded naive T cells in peripheral blood, and a limited interferon-response signature. In the airway epithelium, we found the highest viral load in goblet and ciliated cells and describe a novel inflammatory epithelial cell population. These cells represent a transitional regenerative state between secretory and ciliated cells; they were found in healthy children and were enriched in paediatric and adult COVID-19 patients. Epithelial cells display an antiviral and neutrophil-recruiting gene signature that is weaker in severe paediatricversusadult COVID-19. Our matched blood and airway samples allowed us to study the spatial dynamics of infection. Lastly, we provide a user-friendly interface for this data1as a highly granular reference for the study of immune responses in airways and blood in children.

Background: While pregnant women have been identified as a potentially at-risk group concerning COVID-19 infection, little is known regarding the susceptibility of the fetus to infection. Co-expression of ACE2 and TMPRSS2 has been identified as a pre-requisite for infection, and expression across different tissues is known to vary between children and adults. However, the expression of these proteins in the fetus is unknown. Methods: We performed a retrospective analysis of single cell data repositories. This data was then validated at both gene and protein level by performing qRT-PCR and two-colour immunohistochemistry on a library of second-trimester human fetal tissues. Findings: TMPRSS2 is present at both gene and protein level in the predominantly epithelial fetal tissues analysed. ACE2 is present at significant levels, only in the fetal intestine and kidney and is not expressed in the fetal lung. The placenta is also negative for the two proteins both during development and at term. Interpretation: This dataset indicates that the lungs are unlikely to be a viable route of SARS-CoV2 fetal infection. The fetal kidney, despite presenting both the proteins required for the infection, is anatomically protected from the exposure to the virus. However, the GI tract is likely to be susceptible to infection due to its high co-expression of both proteins, as well as its exposure to potentially infected amniotic fluid. Funding Information: This work was made possible by an MRC / UKRI COVID-19 Rapid response initiative grant (MR/V028480/1). Declaration of Interests: The authors declare no conflicts of interest related to this work or its developments. DC is founder, shareholder, and consultant of Next Generation Diagnostic SRL. Ethics Approval Statement: Human fetal tissues were obtained with consent through the Human Developmental Biology Resource (HDBR; REC 18/LO/0822 – IRAS 244325; Project ID 2000478). Placental samples were obtained at delivery of an uncomplicated, full-term pregnancy (median 39 weeks PCW [Range 38+1 -39+4] for 6 patients recruited through the EVERREST Prospective Study as normal controls (National Research Ethics reference 13/LO/1254), NCT02097667 registered 31st October 2013[10].

Summary Explosion of gene therapy approaches for treating rare monogenic and common liver disorders created an urgent need for disease models able to replicate human liver cellular environment. Available models lack 3D liver structure or are unable to survive in long-term culture. We aimed to generate and test a 3D culture system that allows long-term maintenance of human liver cell characteristics. The in vitro whole-organ “Bioreactor grown Artificial Liver Model” (BALM) employs a custom-designed bioreactor for long-term 3D culture of human induced pluripotent stem cells-derived hepatocyte-like cells (hiHEPs) in a mouse decellularized liver scaffold. Adeno-associated viral (AAV) and lentiviral (LV) vectors were introduced by intravascular injection. Substantial AAV and LV transgene expression in the BALM-grown hiHEPs was detected. Measurement of secreted proteins in the media allowed non-invasive monitoring of the system. We demonstrated that humanized whole-organ BALM is a valuable tool to generate pre-clinical data for investigational medicinal products., Graphical Abstract, Highlights • Generation of a perfused humanized in vitro whole liver bioreactor model: BALM • BALM improves maturation and long-term survival of human iPS-derived hepatocytes • BALM allows viral transduction of human iHEPs through its vasculature • BALM provides a tool for gene therapy testing of human iHEPs, Clinical Genetics; Bioengineering; Tissue Engineering

Several paediatric gastrointestinal diseases result in life-shortening organ failure. For many of these conditions, current therapeutic options are suboptimal and may not offer a cure. Regenerative medicine is an inter-disciplinary field involving biologists, engineers, and clinicians that aims to produce cell and tissue-based therapies to overcome organ failure. Exciting advances in stem cell biology, materials science, and bioengineering bring engineered gastrointestinal cell and tissue therapies to the verge of clinical trial. In this review, we summarise the requirements for bioengineered therapies, the possible sources of the various cellular and non-cellular components, and the progress towards clinical translation of oesophageal and intestinal tissue engineering to date.

Aim: To assess nonoperative management (NOM) of uncomplicated appendicitis (UC-appy) in children to determine factors influencing prognosis and review the literature. Materials and Methods: All UC-...

Anatomical segmentectomy is an advantageous procedure because it spares healthy lung that has potential to show compensatory growth after lung resection and decreases the risk of air leak and residual resection, which becomes a problem in wedge resection. However, anatomical segmentectomy has not become a common procedure in pediatrics because it requires more complicated procedure than lobectomy or wedge resection, especially in patients with a history of pulmonary infection. In this case report, anatomical basal segmentectomy was safely performed with magnified vision by a hybrid video-assisted thoracic surgery (VATS) approach in a 6-year-old girl with intralobar pulmonary sequestration after severe pneumonia. The result suggests that the indications for hybrid VATS segmentectomy can expand further to include segmental lesions in children.

Aim of the study Tissue engineering appears as a potential alternative treatment for long-gap esophageal atresia, for which otherwise there is few treatment options. However, lack of biocompatibility of synthetic materials used in preclinical experiments hampered regeneration of functional muscle layers, eventually leading stricture in the oesophagus or displacement of the material. To overcome this problem, we took advantage of cell-based bioengineering in which progenitor cells with myogenic potential were seeded into extracellular matrix (ECM) scaffolds obtained by decellularization of piglets’ oesophagi. Methods Oesophagi were harvested from piglets and decellularized through two cycle of the detergent-enzymatic treatment (DET) in tailored bioreactors. Mesoangioblasts (MABs) and fibroblasts (FBs) were isolated from the biopsy of human skeletal muscle and expanded. The cells were co-seeded into the ECM scaffolds, at a proportion of 85% MABs and 15% FBs. The seeded oesophagi were cultured in the dynamic condition, in which custom designed bioreactors generate continuous flow of cell culture media inside the lumen. Incubation was maintained for up to 10 days. Results Histology of decellularized oesophagi showed absence of the native cells. The ECM construction of the scaffold was comparable to native oesophagus, preserving distinctive layers. Immunohistochemistry of the repopulated oesophagi identified migration of the cells from the injected sites and differentiation of MABs to smooth muscle cells with expression of SM22 and αSMA. Co-seeded FB distributed along the scaffold maintaining the initial proportion of cells (figure 1). Conclusions We demonstrated efficient decellularization by DET and migration and differentiation of MABs in the ECM scaffold promoted by co-seeding with FBs. Utilization of an oesophagus scaffold from piglets, which has a similar size to human neonates’ oesophagus, will be promising strategy for clinical application of regenerative medicine in humans.

Introduction Therapeutic options for long-gap oesophageal atresia are characterized by poor outcomes with impact on the quality of life. Tissue Engineered (TE) oesophagus could help to fill this gap. Epithelization is a critical factor to avoid long-term complication as strictures. Therefore, for a TE strategy, is crucial to create and maintain a functional epithelium. The aim of our study was to test the capacity of pig oesophageal epithelial cells (PigOEC) to engraft in oesophagus decellularized scaffolds in an in-vitro model. Methods Rat oesophagi were decellularized to prepare scaffolds using a modified detergent-enzymatic treatment protocol. PigOEC were isolated via mechanic-enzymatic dissociation from full-thickness oesophageal samples and plated over lethally-irradiated 3T3 feeder cells. PigOEC were expanded, characterized, and seeded on the inner surface of slit-open scaffolds. Cells were evaluated weekly up to 28 days. Viability was determined by colorimetric assay for cell metabolic activity (MTT assay) and samples were also processed for histological analyses. Results PigOEC were expanded long-term in culture where they showed features comparable to other mammalian epithelial cells. Seeded PigOEC successfully adhered to and covered the entire surface of the scaffolds; they were proliferating and formed a multi-layered epithelium expressing integrin α6 (CD49f) and cytokeratin (CK) 5/14 only in the basal compartment. Discussion Epithelial cells are crucial to restore the oesophageal functional barrier. We have demonstrated in vitro growth capacity of PigOEC that could differentiate and partially stratify upon seeding on decellularized scaffolds. The next steps will be testing full stratification capacity and survival of cultivated PigOEC in an in vivo model. These results support the use of PigOEC to construct a TE oesophagus for a pre-clinical study.

Background and aim of the study The animal models of congenital diaphragmatic hernia (CDH) have contributed to identify several signaling pathways potentially associated to the pathogenesis of lung hypoplasia. However, due to their in vivo nature, these models can only demonstrate the consequence of the malformation and thus are not adequate to evaluate different factors which may have influence on pulmonary hypoplasia separately. In particular, it is still unclear at what extent physical constraint produced by herniated abdominal viscera affects the lung development. We aim at developing a novel ex vivo model harnessing an innovative three-dimensional (3D) printing technique to recapitulate the lung development impaired by physical constraint in CDH. Methods Lungs harvested from E12.5 mouse embryos were embedded in Matrigel solution and maintained in air-liquid interphase (ALI) culture conditions. On the following day (equivalent to E13.5), a 3D structure surrounding the outer surface of the left lobe was built by polymerization of a chemically modified Polyethylene-glycol (PEG) solution, which was added to Matrigel and selectively cross-linked through a two-photon laser. Main results The 3D structure mimics the physical constraint observed in CDH. Live imaging demonstrates decreased growth and delayed branching impeded by 3D structure. After 4 days of culture, the size of the lobe and the number of epithelial branching of the lung surrounded by 3D structure were significantly decreased compared to the control lungs cultured without physical constraint. Conclusions We envision our model as an innovative way to investigate the pathogenesis of pulmonary hypoplasia of CDH. This model has a potential to be applied to human embryo, paving the way for a deeper understanding of the molecular pathways implicated in the mechanism of pulmonary hypoplasia.

We investigated the relationship between the affected lobe and symptom onset in prenatally diagnosed congenital pulmonary airway malformation (CPAM). 53 CPAM patients diagnosed prenatally were reviewed retrospectively by creating 2 groups according to symptom onset. Group Sneo: (symptomatic during the neonatal period; n = 13) and group S > neo: (symptomatic after the neonatal period; n = 40) were compared for type of CPAM, affected lobes, types of symptoms/infections, treatment, duration of follow-up, and histopathology. Requirement for surgery (Sx) was then used to create three subgroups: Sneo + Sx, S > neo + Sx, and Sx−. Some cases had multiple affected lobes. In Sneo, symptoms developed in 55.6%, 50.0%, 0%, 0%, and 36.8% of right upper lobes (RUL), right middle lobes (RML), right lower lobes (RLL), left upper lobes (LUL), and left lower lobes (LLL) diagnosed with CPAM, prenatally. In S > neo, symptoms developed in 0%, 0%, 6.3%, 55.6%, and 33.3% of RUL, RML, RLL, LUL, and LLL diagnosed with CPAM, prenatally. In prenatally diagnosed CPAM, RUL and RML lesions are more likely to become symptomatic in neonates, and LUL lesions in infants. Surgery is recommended before the onset of respiratory infections after 1 year of age.

Explosion of gene therapy approaches for treating rare monogenic and common liver disorders created an urgent need for disease models able to replicate human liver cellular environment. Available models lack 3D liver structure or are unable to survive in long-term culture. We aimed to generate and test a 3D culture system that allows long-term maintenance of human liver cell characteristics. The in vitro whole-organ "Bioreactor grown Artificial Liver Model" (BALM) employs a custom-designed bioreactor for long-term 3D culture of human induced pluripotent stem cells-derived hepatocyte-like cells (hiHEPs) in a mouse decellularized liver scaffold. Adeno-associated viral (AAV) and lentiviral (LV) vectors were introduced by intravascular injection. Substantial AAV and LV transgene expression in the BALM-grown hiHEPs was detected. Measurement of secreted proteins in the media allowed non-invasive monitoring of the system. We demonstrated that humanized whole-organ BALM is a valuable tool to generate pre-clinical data for investigational medicinal products. ispartof: ISCIENCE vol:23 issue:12 ispartof: location:United States status: published

Laparoscopic percutaneous extraperitoneal closure (LPEC) has become routine for repairing pediatric inguinal hernia (IH). Reports on the effective repair of IH in challenging cases, such as extremely low birth weight infants (ELBWI) who become symptomatic soon after birth and have surgery before 1 year of age, are rare; and conventional herniotomy (CH) in ELBWI requires extensive experience of neonatal surgery. We compared LPEC with CH for treating ELBWI with IH. Consecutive ELBWI with IH treated by either LPEC (n = 17) or CH (n = 22) before 1 year of age between 2012 and 2017 were reviewed. LPEC were performed by consultant pediatric surgeons (CPS; n = 3) with experience of at least 200 cases each. In CH, 11 cases were treated by CPS and 11 by CPS-supervised surgical trainees. There were no intraoperative complications. Operative time and anesthesia time for bilateral IH repairs were both shorter in LPEC. Postoperative sequelae were recurrence (LPEC; n = 1; repaired by redo LPEC 2 months after the initial repair) and intravenous rehydration (CH; n = 1; for persistent post-anesthetic vomiting). Recovery was unremarkable in all cases without additional analgesia. LPEC would appear to be a viable option for treating IH in ELBWI, especially bilateral cases.

INTRODUCTION We prospectively reviewed 41 male infants younger than 12 months old who had presented with severe incarcerated inguinal hernia between 2014 and 2016 and had been treated by laparoscopic percutaneous extraperitoneal closure (LPEC) or conventional open repair (CO). METHODS Operative times and intraoperative findings were evaluated. Scrotal/testicular status were assessed preoperatively, 1 week, and 4 weeks after surgery. RESULTS There were 21 boys treated by LPEC and 20 by CO. Mean ages and mean weights at surgery were similar between the groups. The mean operative time was 19.7 min for LPEC and 45.8 min for CO (P

Background Laparoscopic percutaneous extraperitoneal closure (LPEC) has become a common procedure for repairing inguinal hernia. As a laparoscopic approach, pediatric surgical trainees require more training to learn LPEC than a traditional open approach. This study aimed to clarify the experience needed to acquire the skill to perform LPEC adequately. Methods This descriptive single-center study used clinical data from patients who underwent LPEC between May 2009 and May 2016. The mean operative time for ten consecutive unilateral repairs was used as an index of proficiency with the procedure. The number of repairs performed before the mean operative time became less than 20 min was evaluated for each trainee. Results During the study period, six pediatric surgical trainees participated in the training independently. The number of the patients was 987. The total number of repairs was 1436, including 538 unilateral repairs and 449 concurrent bilateral repairs. Overall, the mean operative time was 21.8 ± 8.1 min for unilateral repair and 31.4 ± 9.7 min for concurrent bilateral repairs. The mean number of repairs performed before the acquisition of skill for dexterous LPEC was 125.1 ± 29.5. Conclusions Although there were individual differences, all trainees acquired the skill to perform LPEC adequately within one year. With appropriate guidance, LPEC can become a standard technique for pediatric surgical trainees, along with traditional open surgery. These results provide valuable information for planning LPEC training.

Introduction Jejunoileal atresia (JIA) is a major congenital anomaly that requires surgical intervention in the neonatal period. During follow-up after surgery, there is usually a period of catch-up growth (CUG) that is sufficient for patients to regain normal weight for age. However, in some cases, CUG is inadequate. The aim of this study was to assess postoperative JIA patients to determine factors that may be associated with good CUG. Material and Methods We retrospectively reviewed JIA patients treated at our institution by classifying them into three groups based on a comparison of postoperative weight with standard weight for healthy matched controls; that is, more than mean at 12 months after surgery (group M+), less than mean at 12 months after surgery but more than mean at 24 months after surgery because of CUG (group M-CUG+), less than mean at 24 months after surgery because there was no CUG (group M-CUG−). The following parameters were evaluated: gestational age, birth weight, sight of atresia: jejunum or ileum, length of residual small intestine, ratio of the length of residual small intestine to the predicted length of small intestine for matched gestational age (RP ratio), and duration of parenteral nutrition. Results A total of 42 patients were reviewed and classified into group M+ ( n = 13), group M-CUG+ ( n = 11), and group M-CUG− ( n = 18). There were no significant differences in gestational age, birth weight, and duration of parenteral nutrition between the three groups. Incidence of JIA according to site was also similar. Length of residual small intestine was not significantly different between the three groups, but RP ratios were significantly higher in M+ (84.7 ± 15.4%) and M-CUG+ (83.8 ± 17.7%) compared with M-CUG− (69.2 ± 18.1%) ( p = 0.02, respectively). Conclusions A higher RP ratio (approximately 84%) would appear to be conducive to CUG while a lower ratio (less than 70%) was not. Actual length of residual small intestine was not relevant to CUG. We recommend calculating the RP ratio in postoperative JIA patients and using 70% as a cutoff value to predict patients with poor potential for CUG who may benefit from more aggressive nutritional support to achieve normal growth.

Intensive treatment including surgery for patients with trisomy 13 (T13) remains controversial. This study aimed to evaluate the safety and efficacy of noncardiac surgical intervention for T13 patients. Medical records of patients with karyotypically confirmed T13 treated in the neonatal intensive care unit in Nagano Children's Hospital from January 2000 to October 2016 were retrospectively reviewed, and data from patients who underwent noncardiac surgery were analyzed. Of the 20 patients with T13, 15 (75%) underwent a total of 31 surgical procedures comprising 15 types, including tracheostomy in 10 patients and gastrostomy in 4. Operative time, anesthesia time, and amount of bleeding are described for the first time in a group of children with T13. All the procedures were completed safely with no anesthetic complications or surgery-related death. The overall rate of postoperative complications was 19.3%. Patients receiving tracheostomy had stable or improved respiratory condition. Six of them were discharged home and were alive at the time of this study. These results suggest at least short-term safety and efficacy of major noncardiac surgical procedures, and long-term efficacy of tracheostomy on survival or respiratory stabilization for home medical care of children with T13. Noncardiac surgical intervention is a reasonable choice for patients with T13.

Extralobar pulmonary sequestration (EPS) can occasionally be found incidentally in congenital diaphragmatic hernia (CDH). Extralobar pulmonary sequestration usually arises in the chest or the abdomen; rarely in the diaphragm. We report a neonatal case of antenatally diagnosed CDH associated with intradiaphragmatic EPS.

We present EDCAT (epidural catheter-assisted Deflux(®) treatment) for treating vesicoureteral reflux (VUR) and confirming ureteric patency after Deflux(®) treatment.We treated 147 ureters in 101 children (M:F 62:39; VUR ≤ grade III: n = 72; VUR ≥ grade IV: n = 75) using EDCAT between 2011 and 2014. EDCAT involves injecting 1-3 mL of diluted indigo carmine solution through an epidural anesthesia catheter inserted into the Deflux(®)-treated ureter and observing for up to 15 min to confirm patency.For EDCAT, mean age was 4.9 years and mean operative time was 30.1 ± 12.1 min; overall cure of VUR after initial treatment was 87.7 % for VUR grades I-V, 88.9 % for VUR ≤ grade III, and 86.6 % for VUR ≥ grade IV; VUR was cured in 129/147 after 1 treatment, 7/18 after 2 treatments, 7/11 after 3 treatments, and persistent in 4/4. We experienced 1 case of obstruction after an EDCAT catheter was removed before confirming patency. EDCAT catheters were left overnight in 2 ureters in 2 cases when patency could not be confirmed after 15 min to prevent obstruction. Both did not develop obstruction. Four ureters with recurrence of VUR (all grade ≤ II) are being observed.EDCAT allows ureteric patency to be confirmed immediately and prevents obstruction.

Extraosseous ewing sarcoma (EES) is a rare soft-tissue tumor usually found in the extremities or paraspinal region. We describe the case of a 4-year-old boy with a large cystic mass in the mesentery diagnosed as mesenteric lymphangioma preoperatively and as EES after partial resection and histopathological examination. EES in the mesentery is extremely rare, with only 2 reports described in the English literature. This represents the first report of EES in a child.

Colonoscopy in an 11-year-old boy identified a large long pedunculated colonic duplication originating from the mesenteric side of the cecum extending to the sigmoid colon that did not share a common wall with the native colon and had become intussuscepted. Following uneventful excision, normal growth resumed after resolution of all symptoms.