Active microparticle propulsion pervasively powered by asymmetric AC field electrophoresis.

Hypothesis: Symmetry breaking in an electric field-driven active particle system can be induced by applying a spatially uniform, but temporally non-uniform, alternating current (AC) signal. Regardless of the type of particles exposed to sawtooth AC signals, the unevenly induced polarization of the ionic charge layer leads to a major electrohydrodynamic effect of active propulsion, termed Asymmetric Field Electrophoresis (AFEP).

Experiments: Suspensions containing latex microspheres of three sizes, as well as Janus and metal-coated particles were subjected to sawtooth AC signals of varying voltages, frequencies, and time asymmetries.

International Liver Transplantation Society Global Census: First Look at Pediatric Liver Transplantation Activity Around the World.

Background: Over 16 000 children under the age of 15 died worldwide in 2017 because of liver disease. Pediatric liver transplantation (PLT) is currently the standard of care for these patients. The aim of this study is to describe global PLT activity and identify variations between regions.

Unidirectional rotation of micromotors on water powered by pH-controlled disassembly of chiral molecular crystals.

Biological and synthetic molecular motors, fueled by various physical and chemical means, can perform asymmetric linear and rotary motions that are inherently related to their asymmetric shapes. Here, we describe silver-organic micro-complexes of random shapes that exhibit macroscopic unidirectional rotation on water surface through the asymmetric release of cinchonine or cinchonidine chiral molecules from their crystallites asymmetrically adsorbed on the complex surfaces. Computational modeling indicates that the motor rotation is driven by a pH-controlled asymmetric jet-like Coulombic ejection of chiral molecules upon their protonation in water.

Costs of pediatric liver transplantation among commercially insured and Medicaid-insured patients with cholestasis in the US.

Children with rare cholestatic liver diseases, such as Alagille syndrome, progressive familial intrahepatic cholestasis, and biliary atresia typically require liver transplantation (LT). The objective of this analysis was to assess the economic burden of LT on these patients. Health care resource utilization and costs associated with pediatric LT were retrospectively assessed using insurance claims data from the US IBM MarketScan Commercial and Medicaid databases collected between October 2015 and December 2019.

Electro-Orientation and Electro-Rotation of Metallodielectric Janus Particles.

The electro-rotation (EROT) and electro-orientation (EOR) behavior of metallodielectric spherical Janus particles (JP) are studied analytically and verified experimentally. This stands in contrast to previous either heuristic or numerically computed models of JP dipoles. First, we obtain frequency-dependent analytic expressions for the corresponding dipole terms for a JP composed of dielectric and metallic hemispheres by applying the "standard" (weak-field) electrokinetic model and using a Fourier-Legendre collocation method for solving two sets of linear equations.

Travelling-Wave Electrophoresis, Electro-Hydrodynamics, Electro-Rotation, and Symmetry- Breaking of a Polarizable Dimer in Non-Uniform Fields.

A theoretical framework is presented for calculating the polarization, electro-rotation, travelling-wave dielectrophoresis, electro-hydrodynamics and induced-charge electroosmotic flow fields around a freely suspended conducting dimer (two touching spheres) exposed to non-uniform direct current (DC) or alternating current (AC) electric fields. The analysis is based on employing the classical (linearized) Poisson-Nernst-Planck (PNP) formulation under the standard linearized 'weak-field' assumption and using the tangent-sphere coordinate system. Explicit expressions are first derived for the axisymmetric AC electric potential governed by the Robin (mixed) boundary condition applied on the dimer surface depending on the resistance-capacitance circuit (RC) forcing frequency.

Pediatric Liver Transplantation.

Liver transplantation (LT) for children results in excellent short- and long-term patient and graft survival. LT is a lifesaving procedure in children with acute or chronic liver disease, hepatic tumors, and select genetic metabolic diseases in which it can significantly improve quality of life. In this article, the authors discuss the unique aspects of pediatric LT, including the indications, appropriate patient selection and evaluation, allocation of organs, transplant surgery including the use of variant grafts, posttransplant care including immunosuppression management, prognosis, and transition of care.

Factors associated with improved patient and graft survival beyond 1 year in pediatric liver transplantation.

With advances in surgical techniques, medical management, and more equitable allocation systems, children who receive a liver transplantation (LT) today can expect remarkable outcomes early after LT. However, beyond 1 year after transplant, attrition rates have not improved. We reviewed two separate eras (Era 1: January 1995-June 2004 vs.

The role of particle-electrode wall interactions in mobility of active Janus particles driven by electric fields.

Hypothesis: The interaction of active particles with walls can explain discrepancies between experiments and theory derived for particles in the bulk. For an electric field driven metallodielectric Janus particle (JP) adjacent to an electrode, interaction between the asymmetric particle and the partially screened electrode yields a net electrostatic force - termed self-dielectrophoresis (sDEP) - that competes with induced-charge electrophoresis (ICEP) to reverse particle direction.

Experiments: The potential contribution of hydrodynamic flow to the reversal is evaluated by visualizing flow around a translating particle via micro-particle image velocimetry and chemically suppressing ICEP with poly(l-lysine)-g-poly(ethylene glycol) (PLL-PEG).

Variation in Alanine Aminotransferase in Children with Non-Alcoholic Fatty Liver Disease.

Background: Pediatric non-alcoholic fatty liver disease (NAFLD) is a major public health concern. Aminotransferase (ALT) is frequently used for screening and monitoring, but few studies have reported typical patterns of ALT elevation in children. Methods: TARGET-NASH is a real-world longitudinal observational cohort of patients with NAFLD receiving care across the United States.

North American Biliary Stricture Management Strategies in Children After Liver Transplantation: A Multicenter Analysis From the Society of Pediatric Liver Transplantation (SPLIT) Registry.

Biliary strictures affect 4%-12% of pediatric liver transplantations. Biliary strictures can contribute to graft loss if left untreated; however, there remains no consensus on the best course of treatment. Study objectives included analyses of outcomes associated with biliary stricture management strategies via percutaneous transhepatic cholangiography (PTC), endoscopic retrograde cholangiopancreatography (ERCP), or surgery.

Self-thermophoresis of laser-heated spherical Janus particles.

An analytic framework is presented for calculating the self-induced thermophoretic velocity of a laser-heated Janus metamaterial micro-particle, consisting of two conducting hemispheres of different thermal and electric conductivities. The spherical Janus is embedded in a quiescent fluid of infinite expanse and is exposed to a continuous light irradiation by a defocused laser beam. The analysis is carried under the electrostatic (Rayleigh) approximation (radius small compared to wavelength).

Systemic causes of non-dermatologic chronic pruritus in the pediatric population and their management: An unexplored area.

Chronic pruritus associated with systemic diseases in the pediatric population has been infrequently addressed in the literature. This review focuses on chronic pruritus presenting without cutaneous manifestations. Common systemic etiologies include diseases with hepatic, renal, and hematologic origins.

Recurrence of Primary Sclerosing Cholangitis After Liver Transplant in Children: An International Observational Study.

Background And Aims: Recurrent primary sclerosing cholangitis (rPSC) following liver transplant (LT) has a negative impact on graft and patient survival; little is known about risk factors for rPSC or disease course in children.

Approach And Results: We retrospectively evaluated risk factors for rPSC in 140 children from the Pediatric PSC Consortium, a multicenter international registry. Recipients underwent LT for PSC and had >90 days of follow-up.

Microbiome Responses to Vancomycin Treatment in a Child With Primary Sclerosing Cholangitis and Ulcerative Colitis.

The therapeutic effects of off-label oral vancomycin in pediatric and adult primary sclerosing cholangitis (PSC)-inflammatory bowel disease, more commonly PSC-ulcerative colitis (UC), indicate the translational relevance of disease-associated microbiome findings. This is the first report on longitudinal salivary and fecal microbiome changes in a pediatric PSC-UC patient over the first 90 days of vancomycin therapy. Increase in bacterial diversity and abundance changes in , , and were observed.

Travelling-Wave Dipolophoresis: Levitation and Electrorotation of Janus Nanoparticles.

We present a theoretical study of the hydrodynamic and electrokinetic response of both metallic spherical polarized colloids as well as metallodielectic Janus particles, which are subjected to an arbitrary non-uniform ambient electric field (DC or AC forcing). The analysis is based on employing the linearized 'standard' model (Poisson-Nernst-Planck formulation) and on the assumptions of a 'weak' field and small Debye scale. In particular, we consider cases of linear and helical time-harmonic travelling-wave excitations and provide explicit expressions for the resulting dielectrophoretic and induced-charge electrophoretic forces and moments, exerted on freely suspended particles.

Successful response of primary sclerosing cholangitis and associated ulcerative colitis to oral vancomycin may depend on brand and personalized dose: report in an adolescent.

Primary sclerosing cholangitis (PSC) is a rare, progressive liver disease characterized by cholestasis and bile duct fibrosis that has no accepted therapy known to delay or arrest its progression. We report a 23-year-old female patient who at age 14 was diagnosed with moderate pancolonic ulcerative colitis (UC) and at age 15 with small-duct PSC unresponsive to conventional therapy. The patient began single drug therapy with the antibiotic oral vancomycin (OVT) and achieved normalization of liver enzymes and resolution of UC symptoms with colonic mucosal healing.

Care of Pediatric Solid Organ Transplant Recipients: An Overview for Primary Care Providers.

As the number of living pediatric solid organ transplant (SOT) recipients continues to grow, there is an increased likelihood that primary care providers (PCPs) will encounter pediatric SOT recipients in their practices. In addition, as end-stage organ failure is replaced with chronic medical conditions in transplant recipients, there is a need for a comprehensive approach to their management. PCPs can significantly enhance the care of immunosuppressed hosts by advising parents of safety considerations and avoiding adverse drug interactions.

Gastrointestinal Hemorrhage: A Manifestation of the Telomere Biology Disorders.

Objective: To describe the clinical features, therapeutic interventions, and patient outcomes of gastrointestinal (GI) hemorrhage in individuals with a telomere biology disorder, including dyskeratosis congenita, Hoyeraal-Hreidarsson syndrome, Revesz syndrome, and Coats plus.

Study Design: Clinical Care Consortium for Telomere Associated Ailments members were invited to contribute data on individuals with telomere biology disorders at their institutions who experienced GI bleeding. Patient demographic, laboratory, imaging, procedural, and treatment information and outcomes were extracted from the medical record.

The pediatric solid organ transplant experience with COVID-19: An initial multi-center, multi-organ case series.

The clinical course of COVID-19 in pediatric solid organ transplant recipients remains ambiguous. Though preliminary experiences with adult transplant recipients have been published, literature centered on the pediatric population is limited. We herein report a multi-center, multi-organ cohort analysis of COVID-19-positive transplant recipients ≤ 18 years at time of transplant.

Oral Vancomycin, Ursodeoxycholic Acid, or No Therapy for Pediatric Primary Sclerosing Cholangitis: A Matched Analysis.

Background And Aims: Many children with primary sclerosing cholangitis (PSC) receive oral vancomycin therapy (OVT) or ursodeoxycholic acid (UDCA). There is a paucity of data on whether these medications improve outcomes.

Approach And Results: We analyzed retrospective data from the Pediatric PSC Consortium.

Liver transplantation as a novel strategy for resolution of congenital afibrinogenemia in a pediatric patient.

Fibrinogen replacement therapy is a treatment mainstay for patients with afibrinogenemia and significant bleeding. A male infant with congenital afibrinogenemia and several spontaneous hemarthroses commenced cryoprecipitate prophylaxis but developed severe urticarial reactions. He transitioned to a human fibrinogen concentrate (HFC) (RiaSTAP , CSL Behring; 70 mg/kg biweekly) but continued experiencing hemarthroses (estimated annualized bleeding rate [ABR]: 5-6) and severe anaphylactic reactions, despite pre- and postinfusion medications.