Nutritional Status and GI Symptoms in Pediatric Patients with Cystic Fibrosis

BACKGROUND: Cystic fibrosis (CF) is a genetic disorder that affects many organ systems including the lungs and the gastrointestinal tract. Children with CF often suffer from exocrine pancreatic insufficiency (EPI), causing many issues including poor digestion and poor nutrient absorption. It is imperative that children with CF consume greater amounts of calories, fat, protein, and fat-soluble vitamins to maintain healthy BMI. Studies have shown that adequate nutritional status leads to less severe symptoms and increased ability to fight off infection. OBJECTIVE: The purpose of this study was to evaluate the nutritional intake and frequency of GI symptoms in CF participants compared to their non-CF siblings. METHODS: Participants with CF and their siblings without CF were recruited for this study. Each participant completed a food frequency questionnaire and a GI symptom questionnaire. Data from the food frequency questionnaire was analyzed to determine the approximate composition of each food or drink that was reported. These values were then compared to published dietary reference intakes (DRIs) specific to healthy individuals and children with CF. RESULTS: No significant difference was observed in macronutrient intake between CF and non-CF participants. Our CF participants were deficient in non-fermentable fiber (52%), vitamin A (48%), vitamin E (96%), and vitamin K (100%). CF participants consumed excessive calcium (87%), zinc (87%), sodium (87%), iron (91%), and magnesium (83%). Significant differences were observed between CF and non-CF nutrient intakes of zinc (p=0.05), iron (p=0.04), vitamin A (p=0.03), vitamin E (p=0.003), vitamin C (p=0.05), and vitamin B-12 (p=0.03). CF participants experienced more frequent GI symptoms than non-CF participants. Among CF participants, individuals with the homozygous f508del mutation experienced more frequent GI symptoms than those with the heterozygous f508del mutation. CONCLUSIONS: All participants were eating well and meeting their macronutrient goals. Some dietary deficiencies existed in CF participants, including non-fermentable fiber, and vitamins A, E, and K. Exploring their clinical effects will be a future area of focus. GI symptoms were common in participants with CF, highlighting the need for interventions in this area. Also, GI symptoms in homozygous f508del patients were more frequent than in heterozygous f508del patients. These findings will be used in larger analyses to assess links between dietary intake and composition of the gut microbiome.https://digitalcommons.unmc.edu/surp2021/1009/thumbnail.jp

Canonical quantum gravity in the Vassiliev invariants arena: II. Constraints, habitats and consistency of the constraint algebra

In a companion paper we introduced a kinematical arena for the discussion of the constraints of canonical quantum gravity in the spin network representation based on Vassiliev invariants. In this paper we introduce the Hamiltonian constraint, extend the space of states to non-diffeomorphism invariant ``habitats'' and check that the off-shell quantum constraint commutator algebra reproduces the classical Poisson algebra of constraints of general relativity without anomalies. One can therefore consider the resulting set of constraints and space of states as a consistent theory of canonical quantum gravity.Comment: 20 Pages, RevTex, many figures included with psfi

Lattice knot theory and quantum gravity in the loop representation

We present an implementation of the loop representation of quantum gravity on a square lattice. Instead of starting from a classical lattice theory, quantizing and introducing loops, we proceed backwards, setting up constraints in the lattice loop representation and showing that they have appropriate (singular) continuum limits and algebras. The diffeomorphism constraint reproduces the classical algebra in the continuum and has as solutions lattice analogues of usual knot invariants. We discuss some of the invariants stemming from Chern--Simons theory in the lattice context, including the issue of framing. We also present a regularization of the Hamiltonian constraint. We show that two knot invariants from Chern--Simons theory are annihilated by the Hamiltonian constraint through the use of their skein relations, including intersections. We also discuss the issue of intersections with kinks. This paper is the first step towards setting up the loop representation in a rigorous, computable setting.Comment: 23 pages, RevTeX, 14 figures included with psfi