A review of animal models for post-operative pericardial adhesions.

Post-operative pericardial adhesions remain a serious complication after cardiac surgery that can lead to increased morbidity and mortality. Fibrous adhesions can destroy tissue planes leading to injury of surrounding vasculature, lengthening of operation time, and increased healthcare costs. While animal models are necessary for studying the formation and prevention of post-operative pericardial adhesions, a standardized animal model for inducing post-operative pericardial adhesions has not yet been established.

A quality improvement initiative to standardize time to initiation of enteral feeds after non-surgical necrotizing enterocolitis using a consensus-based guideline.

Background: Recent evidence demonstrates that earlier feeding may be beneficial after non-surgical necrotizing enterocolitis (NEC). We aimed to decrease time to reach full enteral feeds by 20% post-NEC by standardizing time to reinitiate feeds.

Methods: We implemented a consensus-based guideline for earlier feeding post-NEC.

Impact of the Coronavirus (COVID-19) Pandemic on the Care of Pediatric Acute Appendicitis.

Background: Appendicitis is the most common abdominal surgical emergency in children. With the rise of the Coronavirus-19 pandemic, quarantine measures have been enforced to limit the viral transmission of this disease. The purpose of this study was to identify differences in the clinical presentation and outcomes of pediatric acute appendicitis during the Coronavirus-19 pandemic.

Botox, Abdominal Wall Transection, and Body Positioning: A Case of Complex Abdominal Wall Reconstruction With Seat Belt Syndrome.

Seat belt syndrome (SBS) represents all injury profiles associated with seat belt injuries and motor vehicle crashes (MVCs). Seat belt syndrome classically presents with a superficial seat belt sign that may signify deeper intra-abdominal and/or spinal involvement. The amount of force transmitted from the restraint to the passenger ultimately dictates the amount and severity of the injury.

Virtual Visits for Outpatient Burn Care During the COVID-19 Pandemic.

Burn-injured patients must frequently travel long distances to regional burn centers, creating a burden on families and impairing clinical outcomes. Recent federal policies in response to the coronavirus pandemic have relaxed major barriers to conducting synchronous videoconference visits in the home. However, the efficacy and benefits of virtual visits relative to in-person visits remained unclear for burn patients.

Adhesion barriers in cardiac surgery: A systematic review of efficacy.

Background: Postoperative pericardial adhesions have been associated with increased morbidity, mortality, and surgical difficulty. Barriers exist to limit adhesion formation, yet little is known about their use in cardiac surgery. The study presented here provides the first major systematic review of adhesion barriers in cardiac surgery.

Rapunzel Syndrome: A Rare Case of Small Bowel Intussusception in a Child.

Trichobezoars are indigestible masses of ingested hair commonly found in the stomach, often presenting with symptoms related to gastric outlet obstruction and severity related to the mass's size and location. Gastrointestinal complications include ulceration, perforation, peritonitis, pancreatitis, obstructive jaundice, pneumatosis intestinalis, and intussusception. Management of trichobezoars differs from that of other forms of bezoars, which can often be addressed with chemical dissolution.

A predictive model for preterm babies born < 30 weeks gestational age who will not attain full oral feedings.

Objective: Develop a model to predict gastrostomy tube (GT) for feeding at discharge in infants born < 30 weeks' (w) gestational age (GA).

Study Design: A single-center retrospective study at academic NICU. Total of 391 (78 GT, 313 non-GT) infants < 30 w GA admitted in 2015-2018 split into test (15-16) and validation (17-18) cohorts.

Severity of respiratory disease is correlated with time of first oral feeding and need for a gastrostomy tube at discharge in premature infants born at <30 weeks of gestation.

Background: Premature infants who cannot achieve full oral feeds may need a gastrostomy tube (GT) to be discharged from the neonatal intensive care unit (NICU). We previously developed a model to predict which infants born <30 weeks (w) gestational age (GA) will require a GT before discharge. Here we report the detailed respiratory variable data to describe the general respiratory course for infants in the NICU < 30 w GA at birth and the association between different levels of respiratory support with postmenstrual age (PMA) at the time of first oral feeding attempt (PMAff), including later need for GT for discharge.

Are rib fractures stable? An analysis of progressive rib fracture offset in the acute trauma setting.

Background: Rib fractures serve as both a marker of injury severity and a guide for clinical decision making for trauma patients. Although recent studies have suggested that rib fractures are dynamic, the degree of progressive offset remains unknown. The purpose of this study was to further characterize the change that takes place in the acute trauma setting.

Cardiopulmonary Resuscitation-Induced Hardware Failure After Surgical Stabilization of Flail Chest.

Flail chest occurs when three or more ribs have concurrent fractures in two or more places. Flail chest is a marker of injury severity and is associated with increased morbidity and mortality. The management of flail chest includes multiple nonoperative components in addition to surgical stabilization, which has been shown to lower mortality rates to those of multiple rib fractures with a stable chest wall (i.

Intrinsic islet heterogeneity and gap junction coupling determine spatiotemporal Ca²⁺ wave dynamics.

Insulin is released from the islets of Langerhans in discrete pulses that are linked to synchronized oscillations of intracellular free calcium ([Ca(2+)]i). Associated with each synchronized oscillation is a propagating calcium wave mediated by Connexin36 (Cx36) gap junctions. A computational islet model predicted that waves emerge due to heterogeneity in β-cell function throughout the islet.

Connexin 36 mediates blood cell flow in mouse pancreatic islets.

The insulin-secreting β-cells are contained within islets of Langerhans, which are highly vascularized. Blood cell flow rates through islets are glucose-dependent, even though there are no changes in blood cell flow within in the surrounding exocrine pancreas. This suggests a specific mechanism of glucose-regulated blood flow in the islet.

Connexin-36 gap junctions regulate in vivo first- and second-phase insulin secretion dynamics and glucose tolerance in the conscious mouse.

Insulin is secreted from the islets of Langerhans in coordinated pulses. These pulses are thought to lead to plasma insulin oscillations, which are putatively more effective in lowering blood glucose than continuous levels of insulin. Gap-junction coupling of β-cells by connexin-36 coordinates intracellular free calcium oscillations and pulsatile insulin release in isolated islets, however a role in vivo has not been shown.

Gap junctions and other mechanisms of cell-cell communication regulate basal insulin secretion in the pancreatic islet.

Cell-cell communication in the islet of Langerhans is important for the regulation of insulin secretion. Gap-junctions coordinate oscillations in intracellular free-calcium ([Ca(2+)](i)) and insulin secretion in the islet following elevated glucose. Gap-junctions can also ensure that oscillatory [Ca(2+)](i) ceases when glucose is at a basal levels.

Defects in beta cell Ca²+ signalling, glucose metabolism and insulin secretion in a murine model of K(ATP) channel-induced neonatal diabetes mellitus.

Aims/hypothesis: Mutations that render ATP-sensitive potassium (K(ATP)) channels insensitive to ATP inhibition cause neonatal diabetes mellitus. In mice, these mutations cause insulin secretion to be lost initially and, as the disease progresses, beta cell mass and insulin content also disappear. We investigated whether defects in calcium signalling alone are sufficient to explain short-term and long-term islet dysfunction.

Quantitative measurement of zinc secretion from pancreatic islets with high temporal resolution using droplet-based microfluidics.

We assayed glucose-stimulated insulin secretion (GSIS) from live, murine islets of Langerhans in microfluidic devices by the downstream formation of aqueous droplets. Zinc ions, which are cosecreted with insulin from beta-cells, were quantitatively measured from single islets with high temporal resolution using a fluorescent indicator, FluoZin-3. Real-time storage of secretions into droplets (volume of 0.

Real-time, multidimensional in vivo imaging used to investigate blood flow in mouse pancreatic islets.

The pancreatic islets of Langerhans are highly vascularized micro-organs that play a key role in the regulation of blood glucose homeostasis. The specific arrangement of endocrine cell types in islets suggests a coupling between morphology and function within the islet. Here, we established a line-scanning confocal microscopy approach to examine the relationship between blood flow and islet cell type arrangement by real-time in vivo imaging of intra-islet blood flow in mice.

Gap junction coupling and calcium waves in the pancreatic islet.

The pancreatic islet is a highly coupled, multicellular system that exhibits complex spatiotemporal electrical activity in response to elevated glucose levels. The emergent properties of islets, which differ from those arising in isolated islet cells, are believed to arise in part by gap junctional coupling, but the mechanisms through which this coupling occurs are poorly understood. To uncover these mechanisms, we have used both high-speed imaging and theoretical modeling of the electrical activity in pancreatic islets under a reduction in the gap junction mediated electrical coupling.

Dimethyl amiloride improves glucose homeostasis in mouse models of type 2 diabetes.

Dimethyl amiloride (DMA) enhances insulin secretion in the pancreatic beta-cell. DMA also enhances time-dependent potentiation (TDP) and enables TDP to occur in situations where it is normally absent. As we have demonstrated before, these effects are mediated in part through inhibition of neuronal nitric oxide synthase (nNOS), resulting in increased availability of arginine.

Direct effect of cholesterol on insulin secretion: a novel mechanism for pancreatic beta-cell dysfunction.

Objective: Type 2 diabetes is often accompanied by abnormal blood lipid and lipoprotein levels, but most studies on the link between hyperlipidemia and diabetes have focused on free fatty acids (FFAs). In this study, we examined the relationship between cholesterol and insulin secretion from pancreatic beta-cells that is independent of the effects of FFAs.

Research Design And Methods: Several methods were used to modulate cholesterol levels in intact islets and cultured beta-cells, including a recently developed mouse model that exhibits elevated cholesterol but normal FFA levels.

Mechanisms of time-dependent potentiation of insulin release: involvement of nitric oxide synthase.

Time-dependent potentiation (TDP) of insulin release is normally absent in mice. However, we recently demonstrated that TDP occurs in mouse islets under conditions of forced decrease of intracellular pH (pH(i)) associated with elevated NADPH+H(+) (NADPH) levels. Hence, TDP in mouse islets may be kept suppressed by neuronal nitric oxide (NO) synthase (nNOS), an NADPH-utilizing enzyme with alkaline pH optimum.