Leading countries in global science increasingly receive more citations than other countries doing similar research.

Citations and text analysis are both used to study the distribution and flow of ideas between researchers, fields and countries, but the resulting flows are rarely equal. We argue that the differences in these two flows capture a growing global inequality in the production of scientific knowledge. We offer a framework called 'citational lensing' to identify where citations should appear between countries but are absent given that what is embedded in their published abstract texts is highly similar.

Pediatric Surgical Reentry Strategy Following the COVID-19 Pandemic: A Tiered and Balanced Approach.

Background: In response to the COVID-19 pandemic, children's hospitals across the country postponed elective surgery beginning in March 2020. As projective curves flattened, administrators and surgeons sought to develop strategies to safely resume non-emergent surgery. This article reviews challenges and solutions specific to a children's hospital related to the resumption of elective pediatric surgeries.

A neonatal mouse model of intestinal perforation: investigating the harmful synergism between glucocorticoids and indomethacin.

Background: Early postnatal steroids and indomethacin in combination have been shown to increase the risk of spontaneous intestinal perforation (SIP) in infants with extremely low birth weight (ELBW), but the mechanism behind this synergistic effect is unknown.

Materials And Methods: Based on literature in a variety of models suggesting that glucocorticoids and nonsteroidal antiinflammatory agents diminish complementary isoforms of nitric oxide synthase (NOS), we hypothesized that perturbations in NO metabolism contribute to SIP.

Results: Our results using newborn wild-type (WT) and endothelial NOS-knockout (eNOS KO) mice treated with dexamethasone and/or indomethacin indicate that indomethacin treatment diminishes ileal eNOS abundance; dexamethasone treatment diminishes ileal inducible NOS and neuronal NOS (nNOS); 100% of dexamethasone-treated eNOS KO mice die after 3 days; eNOS KO mice treated for 2 days with dexamethasone develop acute pyloric stenosis in association with reduced expression of pyloric nNOS; and isolated ileum from eNOS KO mice treated for 2 days with dexamethasone exhibit a significant decrease in spontaneous peristalsis, decreased circumference, and decreased capacitance for forced volume before ileal perforation compared with ileum from untreated controls.

Insulin-like growth factor-I governs submucosal growth and thickness in the newborn mouse ileum.

Spontaneous intestinal perforations in extremely premature infants are associated with glucocorticoid-induced thinning of the ileal bowel wall. We have previously demonstrated that insulin-like growth factor-1 (IGF-1) is abundant within the submucosa of the newborn mouse ileum but is diminished by glucocorticoid exposure, concomitant with bowel wall thinning. These findings prompted us to hypothesize that IGF-I governs submucosal growth during neonatal gut development and that diminished IGF-I abundance results in submucosal thinning.

Igf-I accelerates ileal epithelial cell migration in culture and newborn mice and may be a mediator of steroid-induced maturation.

We have previously hypothesized that IGF-I is a mediator of dexamethasone (DEX) effect in the newborn mouse ileum-a model designed to mimic the precocious mucosal maturation associated with spontaneous ileal perforations in extremely premature neonates. We have further investigated this hypothesis using in vivo and in vitro models of accelerated epithelial migration (a transient property, temporally associated with mucosal maturation). These experiments include a steroid-treatment model comparing IGF-I immunolocalization with bromo-deoxyuridine (BrdU)-pulse-labeling, as a means of assessing epithelial cell migration, within the ileum of newborn mice that received either daily intraperitoneal injections of DEX (1 microg/gm) or vehicle.