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Nonrespiratory conditions related to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections have been largely described. Ileocolic intussusception has been reported in association with SARS-CoV-2 infection in 10 children, raising the possibility of an etiopathologic role for the virus, but none of these cases documented tissue pathology that would have supported SARS-CoV-2 intestinal inflammation. We report 2 cases of intussusception in patients with SARS-CoV-2 infection who were treated at different pediatric tertiary centers in Europe and provide evidence of the presence of the virus in mesenteric and intestinal tissues of the patients.

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.

OBJECTIVES: Ghrelin is a brain-gut peptide with GH-releasing and appetite-inducing activities and a widespread tissue distribution. Ghrelin is the endogenous ligand of the GH secretagogue receptor type 1a (GHS-R1a), and both ghrelin and the GHS-R1a are expressed in the pituitary. There are conflicting data regarding the effects of ghrelin on cell proliferation. A positive effect on proliferation and activation of the mitogen-activated protein kinase (MAPK) pathway has been found in hepatoma, adipose, cardiomyocyte and prostate cell lines. However, ghrelin has also been shown to have anti-proliferative effects on breast, lung and thyroid cell lines. We therefore examined the effect of ghrelin on the rat pituitary cell line GH3. METHODS: RT-PCR was used for the detection of GHS-R1a and pre-proghrelin mRNA expression in GH3 cells. The effect of ghrelin on cell proliferation was studied using [(3)H]thymidine incorporation; cell counting and the activation of the MAPK pathway were studied using immunoblotting and inhibitors of the extracellular signal-regulated kinase 1 and 2 (ERK 1/2), protein kinase C (PKC) and tyrosine phosphatase pathways. RESULTS: GHS-R1a and ghrelin mRNA expression were detected in GH3 cells. Ghrelin, at 10(-10) to 10(-6) M concentrations, significantly increased [(3)H]thymidine incorporation (at 10(-9) M, 183+/-13% (means+/-s.e.m.) compared with untreated controls), while 12-phorbol 13-myristate acetate (PMA) at 10(-7) M (used as a positive control) caused a 212+/-14% increase. A reproducible stimulatory effect of desoctanoyl ghrelin was also observed on [(3)H]thymidine incorporation (135+/-5%; P

iASPP, an inhibitory member of the ASPP (apoptosis stimulating protein of p53) family, is an evolutionarily conserved inhibitor of p53 which is frequently upregulated in human cancers. However, little is known about the role of iASPP under physiological conditions. Here, we report that iASPP is a critical regulator of epithelial development. We demonstrate a novel autoregulatory feedback loop which controls crucial physiological activities by linking iASPP to p63, via two previously unreported microRNAs, miR-574-3p and miR-720. By investigating its function in stratified epithelia, we show that iASPP participates in the p63-mediated epithelial integrity program by regulating the expression of genes essential for cell adhesion. Silencing of iASPP in keratinocytes by RNA interference promotes and accelerates a differentiation pathway, which also affects and slowdown cellular proliferation. Taken together, these data reveal iASPP as a key regulator of epithelial homeostasis.

BackgroundGhrelin and its receptor play an important role in glucose metabolism and energy homeostasis, and therefore they are functional candidates for genes carrying susceptibility alleles for type 2 diabetes.MethodsWe assessed common genetic variation of the ghrelin (GHRL; five single nucleotide polymorphisms (SNP)) and the ghrelin-receptor (GHSR) genes (four SNPs) in 610 Caucasian patients with type 2 diabetes and 820 controls. In addition, promoter reporter assays were conducted to model the regulatory regions of both genes.ResultsNeither GHRL nor GHSR gene SNPs were associated with type 2 diabetes. One of the ghrelin haplotypes showed a marginal protective role in type 2 diabetes. We observed profound differences in the regulation of the GHRL gene according to promoter sequence variants. There are three different GHRL promoter haplotypes represented in the studied cohort causing up to 45% difference in the level of gene expression, while the promoter region of GHSR gene is primarily represented by a single haplotype.ConclusionThe GHRL and GHSR gene variants are not associated with type 2 diabetes, although GHRL promoter variants have significantly different activities.

Vitamin D has anti-proliferative and proapoptotic effects on several cell types, including breast cancer cells. There have been no studies quantifying the expression of the enzyme 25-hydroxyvitamin D-1-alpha-hydroxylase (1alphaOHase), which converts 25-hydroxyvitamin D to its active metabolite, in breast tissue. We performed real-time RT-PCR to quantity 1alphaOHase and vitamin D receptor (VDR) mRNA in samples of breast cancer, adjacent non-cancerous tissue and normal breast tissue. 1alphaOHase and VDR mRNA were universally expressed, however, 1alphaOHase expression was significantly down-regulated in adjacent non-cancerous tissue from women with breast cancer in comparison to individuals without cancer. VDR was also up-regulated in breast tumours. The vitamin D axis expression in the breast suggests a role for its actions in normal tissue homeostasis and breast cancer pathogenesis. The decreased expression of 1alphaOHase in normal tissue from women with breast cancer may be important in their predisposition to the development of cancer.

Objectives: Somatostatin (SST) analogues play an important role in the medical management of somatotroph pituitary adenomas and new agonists have the potential to be effective in a wider group of pituitary and other tumours. The anti-proliferative effect of SST occurs through multiple mechanisms, one of which is cell-cycle arrest, where p27, a cyclin-dependent kinase inhibitor, is an important regulator. We hypothesised that SST may upregulate p27 protein levels and downregulate the MAP kinase pathway in these tumours. Methods: Human pituitary adenoma cells and rat pituitary cell line (GH3) were cultured and treated in vitro with octreotide and the broad-spectrum SST agonist SOM230 (pasireotide). Immunoblotting for p27 and phospho-ERK (pERK) was performed and proliferation assessed by [3H]-thymidine incorporation. Histological samples from acromegalic patients treated with octreotide before surgery were immunostained for p27 and compared to samples from untreated patients matched for sex, age, tumour size, extension and invasiveness. Results: We detected upregulation of p27 protein levels with SST analogue treatment in vitro in human pituitary adenoma samples. pERK1/2 was inhibited by SST analogues in both the human samples and GH3 cells. SST and its analogues inhibited the proliferation of GH3 cells. p27 immunostaining was stronger in samples from patients with longer preoperative octreotide treatment (more than 6 months) than in samples from patients with shorter treatment periods. Conclusions: This study demonstrates that SST-mediated growth inhibition is associated with the downregulation of pERK and upregulation of p27. More potent and broader-spectrum SST analogues are likely to play an increasing role in the treatment of tumours, where the MAP kinase pathway is overactivated.