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Embryonic stem cell-derived endoderm is critical for the development of cellular therapies for the treatment of disease such as diabetes, liver cirrhosis, or pulmonary emphysema. Here, we describe a novel approach to induce endoderm from mouse embryonic stem (mES) cells using tibronectin-coated collagen gels. This technique results in a homogeneous endoderm-like cell population, demonstrating endoderm-specific gene and protein expression, which remains committed following in vivo transplantation. In this system, activin, normally an endoderm inducer, caused an 80% decrease in the Foxa2-positive endoderm fraction, whereas follistatin increased the Foxa2-positive endoderm fraction to 78%. Our work suggests that activin delays the induction of endoderm through its transient precursors, the epiblast and mesendoderm. Long-term differentiation displays a twofold reduction in hepatic gene expression and threefold reduction in hepatic protein expression of activin-treated cells compared with follistatin-treated cells. Moreover, subcutaneous transplantation of activin-treated cells in a syngeneic mouse generated a heterogeneous teratoma-like mass, suggesting that these were a more primitive population. In contrast, follistatin-treated cells resulted in an encapsulated epithelial-like mass, suggesting that these cells remained committed to the endoderm lineage. In conclusion, we demonstrate a novel technique to induce the direct differentiation of endoderm from mES cells without cell sorting. In addition, our work suggests a new role for activin in induction of the precursors to endoderm and a new endoderm-enrichment technique using follistatin. [ABSTRACT FROM AUTHOR]

Modulation of the immune system may be a viable alternative in the treatment of fulminant hepatic failure (FHF) and can potentially eliminate the need for donor hepatocytes for cellular therapies. Multipotent bone marrow-derived mesenchymal stem cells (MSCs) have been shown to inhibit the function of various immune cells by undefined paracrine mediators in vitro. Yet, the therapeutic potential of MSC-derived molecules has not been tested in immunological conditions in vivo. Herein, we report that the administration of MSC-derived molecules in two clinically relevant forms-intravenous bolus of conditioned medium (MSC-CM) or extracorporeal perfusion with a bioreactor containing MSCs (MSC-EB)-can provide a significant survival benefit in rats undergoing FHF. We observed a cell mass-dependent reduction in mortality that was abolished at high cell numbers indicating a therapeutic window. Histopathological analysis of liver tissue after MSC-CM treatment showed dramatic reduction of panlobular leukocytic infiltrates, hepatocellular death and bile duct duplication. Furthermore, we demonstrate using computed tomography of adoptively transferred leukocytes that MSC-CM functionally diverts immune cells from the injured organ indicating that altered leukocyte migration by MSC-CM therapy may account for the absence of immune cells in liver tissue. Preliminary analysis of the MSC secretome using a protein array screen revealed a large fraction of chemotactic cytokines, or chemokines. When MSC-CM was fractionated based on heparin binding affinity, a known ligand for all chemokines, only the heparin-bound eluent reversed FHF indicating that the active components of MSC-CM reside in this fraction. These data provide the first experimental evidence of the medicinal use of MSC-derived molecules in the treatment of an inflammatory condition and support the role of chemokines and altered leukocyte migration as a novel therapeutic modality for FHF.

Background/objectives: Central database registrations are widely used tools for assessment of clinical results, but their reliability is subject to debate. The aim of this study is to evaluate the reliability of central database registration for Wilms tumor (WT) nephrectomy-related complications., Design/methods: All Dutch patients undergoing WT nephrectomy according to the International Society of Paediatric Oncology (SIOP) 2001 protocol between 2001 and 2013 were evaluated. Results from the central database were analyzed and compared with data found via individual medical records analysis (gold standard)., Results: A total of 179 patients were included. Fourteen (7.8%) patients with a total of 17 complications were identified in the central database. The medical records revealed that 33 (18.4%) of patients had undergone a total of 41 complications (P < 0.001). Operative complications were similar between the groups (P = 0.157). Eleven short-term complications were noted in the central database versus 27 in the medical records (P = 0.059). Significantly more long-term complications, namely, adhesive small-bowel obstruction, were noted from the medical records compared with the central database (7 vs 1, respectively, P < 0.001). Postoperative chemotherapy was significantly delayed by on average 6 days (P < 0.0001) in patients with complications. No significant effect of complications on event-free survival, overall survival, or the relapse rate was recorded., Conclusion: Central database registrations underestimate the incidence of surgery-related complications after WT nephrectomy and need to be regarded with caution., (© 2018 Wiley Periodicals, Inc.)

In children with no prior history of abdominal surgery and no signs of intussusception or incarcerated inguinal hernia, mechanical ileus may have a congenital cause such as malrotation with volvulus or a persistent omphalomesenteric duct. Acquired causes include sigmoid volvulus. We present two cases of mechanical ileus in children. The first case involved a 6-year-old boy who presented with acute abdominal pain and vomiting. An emergency laparotomy was performed, with resection of the omphalomesenteric duct. Recovery was uneventful. The other case concerned a 9-year-old boy who presented with increasing abdominal pain, bilious vomiting and general clinical deterioration. An emergency laparotomy was performed, revealing malrotation with volvulus and intestinal ischaemia. Children with no prior abdominal history who present with symptoms that may be caused by mechanical obstruction should be managed with a view to surgery and without delay, in order to prevent a catastrophic outcome resulting from a congenital or acquired mechanical obstruction.

Fetal hepatocytes (FHEPs) are a potential source of highly proliferative transplantable cells but express low levels of liver-specific functions. We hypothesized that the microenvironment of adult hepatocytes (AHEPs) may upregulate these functions. Primary FHEPs were seeded on top of collagen-sandwiched AHEPs directly or separated by a porous transwell membrane insert. In direct co-cultures, albumin (ALB) secretion, urea synthesis, and cytochrome P450 (CytP450) activity were all approximately 2 times as high as the sum of the corresponding monocultures. Using a transwell porous insert led to similar results, suggesting a major role for soluble factors. When AHEPs and FHEPs were separated after co-culture, they both initially showed significantly higher ALB secretion than control monocultures, whereas urea synthesis was significantly lower for the FHEPs only. Functions of previously co-cultured FHEPs normalized over the course of a week, but AHEP function remained high even after separation. In conclusion, co-culturing AHEPs with FHEPs increases expression of liver-specific functions in both cell types. The effect on FHEPs, but not AHEPs, was reversible. Unraveling the underlying mechanisms and optimizing this phenomenon will be useful in making fetal liver cells a potential cell source for hepatic tissue-engineering applications.