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We show that composite hydrogels comprising methyl cellulose (MC) and cellulose nanocrystal (CNC) colloidal rods display a reversible and enhanced rheological storage modulus and optical birefringence upon heating, i.e., inverse thermoreversibility. Dynamic rheology, quantitative polarized optical microscopy, isothermal titration calorimetry (ITC), circular dichroism (CD), and scanning and transmission electron microscopy (SEM and TEM) were used for characterization. The concentration of CNCs in aqueous media was varied up to 3.5 wt % (i.e, keeping the concentration below the critical aq concentration) while maintaining the MC aq concentration at 1.0 wt %. At 20 °C, MC/CNC underwent gelation upon passing the CNC concentration of 1.5 wt %. At this point, the storage modulus (G′) reached a plateau, and the birefringence underwent a stepwise increase, thus suggesting a percolative phenomenon. The storage modulus (G′) of the composite gels was an order of magnitude higher at 60 °C compared to that at 20 °C. ITC results suggested that, at 60 °C, the CNC rods were entropically driven to interact with MC chains, which according to recent studies collapse at this temperature into ring-like, colloidal-scale persistent fibrils with hollow cross-sections. Consequently, the tendency of the MC to form more persistent aggregates promotes the interactions between the CNC chiral aggregates towards enhanced storage modulus and birefringence. At room temperature, ITC shows enthalpic binding between CNCs and MC with the latter comprising aqueous, molecularly dispersed polymer chains that lead to looser and less birefringent material. TEM, SEM, and CD indicate CNC chiral fragments within a MC/CNC composite gel. Thus, MC/CNC hybrid networks offer materials with tunable rheological properties and access to liquid crystalline properties at low CNC concentrations.

We report the multi-modality treatment of a massive cervicothoracic lymphatic-venous malformation (LVM) in a 13-year-old boy that was present at birth as a small cervical mass. At four years of age, sclerotherapy significantly reduced the size of the malformation but over subsequent years the mass increased dramatically in size and resulted in a consumptive coagulopathy and limited left shoulder function. Treatment with sildenafil was without effect. The consumptive coagulopathy improved with subcutaneous enoxaparin. A multi-disciplinary team excised part of the mass when he was 11 years old. After surgery, gradual enlargement of the mass and rise in d-dimer prompted treatment with sirolimus. Two sessions of sclerotherapy arrested enlargement of the mass. Multi-modality treatment resulted in a marked reduction of the LVM in the child. However, enlargement of the mass and further treatment is anticipated as a cure has not yet been found.

Omphalocele is a congenital condition characterized by midline defect of the anterolateral abdominal wall whereby intra-abdominal contents covered by peritoneal sac are found herniated. It can be defined by size of defect or visceral contents. There are various ways of surgical management of omphalocele. Giant omphalocele presents particular challenge in reconstructing the abdominal wall. In this regard the use of tissues expansion as an adjunct in an attempt to recreate functional abdominal wall domain has been emerging. We are presenting a case of giant omphalocele that was closed with the help of extra peritoneal inter muscular tissue expanders.The patient was born at 37 weeks to a 33 year old healthy gravida 3, para 0 G3P0 mother via planned cesarean section. There were no prenatal, natal or postnatal complications. The giant omphalocele was diagnosed prenatally on screening Ultrasound. The patient remained in the neonatal intensive care unit for 6 weeks. The sac was large with abdominal contents including the entire liver. The sac was allowed to epithelialize completely over the course of two years. Due to the small size of the abdominal wall defect contents of the sac, loss of abdominal domain and inability of the abdominal cavity to accommodate the liver, we chose for rectangular tissue expander placement at age 30 months. 3 months later the patient was planned for tissue expander removal and abdominal wall closure. The tissue expanders were removed and omphalocele closure was performed. The patient has been followed up at 6 months and without recurrence of hernia.The management of giant omphalocele is technically challenging. Use of tissue expansion helps in recreating functional abdominal wall domain. There is growing evidence in the literature supporting the use of intra-abdominal tissue expansion in the management of giant omphalocele however because of hemodynamic consequences we think that the use of rectangular shaped, extra peritoneal, inter muscular tissue expanders is more desirable and has additional advantage of facilitating component separation.

We present the case of a late preterm infant with prenatal concerns for a cloacal anomaly with dilation of bowel and a small bladder. After birth the infant was found to have a presumed uterus didelphys, patent urachus, imperforate anus and total colonic agenesis. This constellation of clinical findings is not described in the literature and no syndrome fits this description. A chromosomal microarray showed a female with normal copy number. It remains unknown if these findings are associated with a syndrome not previously known or occurred as spontaneous changes.

Nontuberculous mycobacterial (NTM) adenitis of the head and neck region is well-described in healthy children, most commonly presenting under the age of 5years. Extracervicofacial NTM adenitis is less common. We present a case of NTM inguinal adenitis in a 2-year-old girl, followed by a systematic review of the literature.

As rates of childhood obesity rise, the frequency of laparoscopic cholecystectomy to treat gallbladder disease in the pediatric population is increasing. Knowledge of biliary anatomy and its variants is vital to performing this operation safely. Duplication of the extrahepatic biliary tree is a rare but important variant. The significance of duplicated common bile duct anatomy is important as these variations may pre-dispose patients to stone formation and obstruction. Here we present the case of an 11-year-old girl with gallstone pancreatitis and a duplicated common bile duct. The patient underwent interval laparoscopic cholecystectomy following resolution of pancreatitis. A duplicated common bile duct type Vb was identified on intraoperative cholangiogram and subsequent endoscopic retrograde cholangiopancreatography.

Superior temporal artery pseudoaneurysms were first described by Thomas Bartholin in 1740, and since then approximately 400 cases have been reported in the literature. It is estimated that of aneurysms that are surgically repaired, traumatic aneurysms, pseudoaneurysms, and arteriovenous (AV) fistulas of the superficial temporal artery (STA) account for 0.5%–2.0%. Of these, only a few reported are in the pediatric population.

Amyand's hernia is an exceedingly rare condition in which the appendix is found in an inguinal hernia. The appendix can be normal, inflamed, infected, or perforated. Here, we present a case of perforated appendicitis in an Amyand's hernia in an extremely preterm infant with subsequent post-operative complications including necrotic bowel and venous thrombosis of the mesentery. This article stresses the importance of complications that can arise in Amyand's hernia, especially in an extremely preterm infant.