Fetal lung underdevelopment is rescued by administration of amniotic fluid stem cell extracellular vesicles in rodents.

Fetal lung underdevelopment, also known as pulmonary hypoplasia, is characterized by decreased lung growth and maturation. The most common birth defect found in babies with pulmonary hypoplasia is congenital diaphragmatic hernia (CDH). Despite research and clinical advances, babies with CDH still have high morbidity and mortality rates, which are directly related to the severity of lung underdevelopment. To date, there is no effective treatment that promotes fetal lung growth and maturation. Here, we describe a stem cell-based approach in rodents that enhances fetal lung development via the administration of extracellular vesicles (EVs) derived from amniotic fluid stem cells (AFSCs). Using fetal rodent models of pulmonary hypoplasia (primary epithelial cells, organoids, explants, and in vivo), we demonstrated that AFSC-EV administration promoted branching morphogenesis and alveolarization, rescued tissue homeostasis, and stimulated epithelial cell and fibroblast differentiation. We confirmed this regenerative ability in in vitro models of lung injury using human material, where human AFSC-EVs obtained following good manufacturing practices restored pulmonary epithelial homeostasis. Investigating EV mechanism of action, we found that AFSC-EV beneficial effects were exerted via the release of RNA cargo. MicroRNAs regulating the expression of genes involved in lung development, such as the miR17-92 cluster and its paralogs, were highly enriched in AFSC-EVs and were increased in AFSC-EV-treated primary lung epithelial cells compared to untreated cells. Our findings suggest that AFSC-EVs hold regenerative ability for underdeveloped fetal lungs, demonstrating potential for therapeutic application in patients with pulmonary hypoplasia.

Experimental necrotizing enterocolitis induces neuroinflammation in the neonatal brain.

BACKGROUND: Necrotizing enterocolitis (NEC) is an inflammatory gastrointestinal disease primarily affecting preterm neonates. Neonates with NEC suffer from a degree of neurodevelopmental delay that is not explained by prematurity alone. There is a need to understand the pathogenesis of neurodevelopmental delay in NEC. In this study, we assessed the macroscopic and microscopic changes that occur to brain cell populations in specific brain regions in a neonatal mouse model of NEC. Moreover, we investigated the role of intestinal inflammation as part of the mechanism responsible for the changes observed in the brain of pups with NEC. METHODS: Brains of mice were assessed for gross morphology and cerebral cortex thickness (using histology). Markers for mature neurons, oligodendrocytes, neural progenitor cells, microglia, and astrocytes were used to quantify their cell populations in different regions of the brain. Levels of cell apoptosis in the brain were measured by Western blotting and immunohistochemistry. Endoplasmic reticulum (ER) stress markers and levels of pro-inflammatory cytokines (in the ileum and brain) were measured by RT-qPCR and Western blotting. A Pearson test was used to correlate the levels of cytokines (ELISA) in the brain and ileum and to correlate activated microglia and astrocyte populations to the severity of NEC. RESULTS: NEC pups had smaller brain weights, higher brain-to-body weight ratios, and thinner cortices compared to control pups. NEC pups had increased levels of apoptosis and ER stress. In addition, NEC was associated with a reduction in the number of neurons, oligodendrocytes, and neural progenitors in specific regions of the brain. Levels of pro-inflammatory cytokines and the density of activated microglia and astrocytes were increased in the brain and positively correlated with the increase in the levels pro-inflammatory cytokines in the gut and the severity of NEC damage respectively. CONCLUSIONS: NEC is associated with severe changes in brain morphology, a pro-inflammatory response in the brain that alters cell homeostasis and density of brain cell populations in specific cerebral regions. We show that the severity of neuroinflammation is associated with the severity of NEC. Our findings suggest that early intervention during NEC may reduce the chance of acute neuroinflammation and cerebral damage.

The Regenerative Potential of Amniotic Fluid Stem Cell Extracellular Vesicles: Lessons Learned by Comparing Different Isolation Techniques.

Extracellular vesicles (EVs) derived from amniotic fluid stem cells (AFSCs) mediate anti-apoptotic, pro-angiogenic, and immune-modulatory effects in multiple disease models, such as skeletal muscle atrophy and Alport syndrome. A source of potential variability in EV biological functions is how EV are isolated from parent cells. Currently, a comparative study of different EV isolation strategies using conditioned medium from AFSCs is lacking. Herein, we examined different isolation strategies for AFSC-EVs, using common techniques based on differential sedimentation (ultracentrifugation), solubility (ExoQuick, Total Exosome Isolation Reagent, Exo-PREP), or size-exclusion chromatography (qEV). All techniques isolated AFSC-EVs with typical EV morphology and protein markers. In contrast, AFSC-EV size, protein content, and yield varied depending on the method of isolation. When equal volumes of the different AFSC-EV preparations were used as treatment in a model of lung epithelial injury, we observed a significant variation in how AFSC-EVs were able to protect against cell death. AFSC-EV enhancement of cell survival appeared to be dose dependent, and largely uninfluenced by variation in EV-size distributions, relative EV-purity, or their total protein content. The variation in EV-mediated cell survival obtained with different isolation strategies emphasizes the importance of testing alternative isolation techniques in order to maximize EV regenerative capacity.

Open Versus Laparoscopic Approach for Morgagni's Hernia in Infants and Children: A Systematic Review and Meta-Analysis.

INTRODUCTION: The laparoscopic repair of Morgagni's hernia (MH) has been reported to be safe and feasible. However, it is still unclear whether laparoscopy is superior to open surgery in repairing MH. MATERIALS AND METHODS: Using a defined search strategy, three investigators independently identified all comparative studies reporting data on open and laparoscopic MH repair in patients <18 years of age. Case reports and opinion articles were excluded. Meta-analysis was conducted according to PRISMA guidelines and using RevMan 5.3. Data are expressed as mean ± SD. RESULTS: Systematic review - Of 774 titles/abstracts screened, 51 full-text articles were analyzed. Three studies were included (92 patients), with 53 (58%) open approaches and 39 (42%) laparoscopy. Meta-analysis - The length of surgery was shorter in laparoscopy (50.5 ± 17.0 min) than in open procedure (90.0 ± 15.0 min; P < .00001). Laparoscopy shortened the length of hospital stay (2.1 ± 1.4 days) versus open surgery (4.5 ± 2.1 days; P < .00001). There was no difference with regards to complications (laparoscopy: 8.8% ± 5.5%, open: 9.4% ± 1.6%; P = .087) and recurrences (laparoscopy: 2.9% ± 5.0%, open: 5.7% ± 1.8%; P = .84). DISCUSSION: Comparative studies indicate that laparoscopic MH repair can be performed in infants and children. Laparoscopy is associated with shortened length of surgery and hospital stay in comparison to open procedure. Prospective randomized studies would be needed to confirm present data.

Gastrostomy Placement in Children: Percutaneous Endoscopic Gastrostomy or Laparoscopic Gastrostomy?

The aim of this study is to compare the outcomes and the complications between the 2 most adopted procedures for gastrostomy placement: percutaneous endoscopic gastrostomy (PEG) and laparoscopic gastrostomy (LG) in children. We present our study on 69 patients (male: 46/female: 23): group 1 (37 patients, 54%) undergoing PEG, group 2 (32 patients, 46%) undergoing LG. A total of 5 major complications were observed all in the PEG group (13.5%), no major complication was observed in the LG group (P-value<0.05). A total of 12 minor complications were observed: 4 occurred in the PEG group (10.8%) and 8 (25%) in the laparoscopic gastrostmoy group, not statistically relevant. We suggest that the LG should be considered the preferred technique for gastrostomy placement in pediatric patients, particularly in newborns, children with significant skeletal malformations, and patients who underwent previous abdominal surgery.

Endobronchial tumor in children: Unusual finding in recurrent pneumonia, report of three cases.

We are reporting 3 cases of pediatric endobronchial tumors presented with recurrent pneumonia. The median age of patients, at time of presentation, was 10.6 years. All patients presented with recurrent pneumonia with a mean time to occurrence, after onset of symptoms, of 14 mo. Bronchoscopy was early performed as part of diagnostic work-up and it revealed an endobronchial mass in every case. Complete surgical resection was performed in all cases, with lung preservation in two of them. Neither post-operative chemotherapy nor radiotherapy was required. The mean duration of follow-up was 7 years and all patients are still alive and disease-free. Recurrent pneumonia, in pediatrics, should raise the suspicion of an obstructing lesion, congenital malformation or systemic disease. A systematic approach is useful for organize the clinicians initial workup. Prompt diagnosis allows parenchymal-sparing surgery, which offers the best chance of cure and reduces clinical and functional complications in these patients.