Renal function in patients on long-term home parenteral nutrition for chronic intestinal failure: a 30 month prospective study

Introduzione: l’incidenza e le cause di insufficienza renale in pazienti in NPD per IICB non sono ancora chiare. Questo studio si è prefisso di valutarle. Materiali e metodi: studio prospettico di 30 mesi condotto in pazienti adulti. funzione renale valutata tramite filtrato glomerulare(eGFR) secondo MDRD(Modification of Diet in Renal Disease), cistatina C. eGFR< 60 ml è stato considerato diagnostico per IRC. Parametri valutati: caratteristiche dell'insufficienza intestinale e programma di NPD, infezioni del catetere venoso centrale (CRBSI). Risultati: 53 hanno terminato il follow-up a 30 mesi e sono stati quindi inclusi nell’analisi statistica. i pazienti sono stati suddivisi in 3 gruppi in base al eGFR: Gruppo A(n.12) pazienti con IRC al baseline, e Gruppo B (N.6) pazienti che sviluppano IRC durante follow up, Gruppo C (n.35) pazienti che mantengono eGFR ≥ 60 ml/min. Conclusioni: durante un follow up di 30 mesi, il 14.6% dei pazienti in NPD ha sviluppato una IRC. La frequenza di CRBSI si è confermata essere un fattore di rischio per la IRC, mentre il volume sembrerebbe avere un ruolo protettivo.Objective: The incidence and causes of chronic renal failure(CRF) in patients on home parenteral nutrition(HPN) remain to be clarified. We investigated renal function outcome in patients on long term HPN for chronic intestinal failure(CIF) due to benign disease. Research Methods & Procedures: A 30 month prospective study was performed on adult patients on HPN at 31/10/2011(baseline). Renal function was evaluated by: estimated glomerular filtration rate (eGFR) according to MDRD(Modification of Diet in Renal Disease) and by serum Cystatin C. eGFR< 60 ml was considered indicative of CRF. Parameters evaluated: characteristics of CIF and HPN program; catheter related bloodstream infection(CRBSI) episodes. Statistic: patients who completed follow up(Fup) period were included in the analysis; non parametric tests. Results: Fifty-three patients were analyzed: 39 short bowel syndrome, 12 chronic intestinal pseudo obstruction, 2 mucosal disease. According to the eGFR at baseline and to its outcome during the Fup, patients were categorized in 3 groups: A) presence of CRF at baseline(n. 12) ; B) development of CRF during Fup(n. 6); C) normal eGFR at both baseline and Fup(n. 35). During Fup, the variation of eGFR was -5.87%/year in group A, -12.75% in B and +1.19 in C(p=0.001). At the end of Fup, Cystatin C was higher in group A than in C(p=0.001). The highest incidence of CRBSI (episodes/year) was observed in group B(p=0.005). The median of the daily volume(ml) of HPN was 1339 in group A, 589 in B and 1960 in C (p=0.202; p=0.082 between B and C). Conclusions: Along a 30 month period, a CRF developed in about 15% of patients on long term HPN. The CRBSI appear a risk factor. The volume of HPN infusion may be a protective factor

Mixed quantum-classical dynamics from the exact decomposition of electron-nuclear motion

We present a novel mixed quantum-classical approach to the coupled electron-nuclear dynamics based on the exact factorization of the electron-nuclear wave function, recently proposed in [A. Abedi, N. T. Maitra, and E. K. U. Gross, Phys. Rev. Lett. 105, 123002 (2010)]. In this framework, classical nuclear dynamics is derived as the lowest order approximation of the time dependent Schr\"odinger equation that describes the evolution of the nuclei. The effect of the time dependent scalar and vector potentials, representing the exact electronic back-reaction on the nuclear subsystem, is consistently derived within the classical approximation. We examine with an example the performance of the proposed mixed quantum-classical scheme in comparison with exact calculations

On the mass of atoms in molecules: Beyond the Born-Oppenheimer approximation

Describing the dynamics of nuclei in molecules requires a potential energy surface, which is traditionally provided by the Born-Oppenheimer or adiabatic approximation. However, we also need to assign masses to the nuclei. There, the Born-Oppenheimer picture does not account for the inertia of the electrons and only bare nuclear masses are considered. Nowadays, experimental accuracy challenges the theoretical predictions of rotational and vibrational spectra and requires to include the participation of electrons in the internal motion of the molecule. More than 80 years after the original work of Born and Oppenheimer, this issue still is not solved in general. Here, we present a theoretical and numerical framework to address this problem in a general and rigorous way. Starting from the exact factorization of the electron-nuclear wave function, we include electronic effects beyond the Born-Oppenheimer regime in a perturbative way via position-dependent corrections to the bare nuclear masses. This maintains an adiabatic-like point of view: the nuclear degrees of freedom feel the presence of the electrons via a single potential energy surface, whereas the inertia of electrons is accounted for and the total mass of the system is recovered. This constitutes a general framework for describing the mass acquired by slow degrees of freedom due to the inertia of light, bounded particles. We illustrate it with a model of proton transfer, where the light particle is the proton, and with corrections to the vibrational spectra of molecules. Inclusion of the light particle inertia allows to gain orders of magnitude in accuracy

Comment on “early efficacy of intra-articular HYADD® 4 (Hymovis®) injections for symptomatic knee osteoarthritis”

We read with great interest the study by Priano titled“Early efficacy of intra-articular HYADD® 4 (Hymovis®) injections for symptomatic knee osteoarthritis.” 1 The author would like to explore the efficacy of intra-articular HYADD 4 (Hymovis) injections for symptomatic knee osteoarthritis. Results from this study are very interesting and promising from a clinical aspect; however, we believe that studying patient’sclinical status with visual analog scale and Western Ontario and McMaster Universities Arthritis Index scale should be supported by biomechanical information. From this point of view, to have more data that could influence the clinical practice, it is important to note the possible action that intraarticular injections of different kinds of hyaluronic acid could have on walking biomechanics using an objective measurement tool as gait analysis. In our opinion, the work by Priano1 is promising because it investigates the efficacy of a new formulation of hyaluronic acid. Nowadays, many hyaluronic acid formulations are approved for clinical use in Europe and the United States. Furthermore, hyaluronic acid injections’ efficacy has been demonstrated also in hip osteoarthritis. 2 However, even if these formulations differ in their chemical– physical properties, joint space half-life, rheological properties, and clinical efficacy, there are few studies that investigate hyaluronic acid’s possible action from a biomechanical point of view. 3,4 From this point of view, we believe that osteoarthritis management and rehabilitation should be prescribed after an objective analysis of functional walking alterations using gait analysis instrumentations. The use of gait analysis should be desirable during diagnosis and follow-up. In fact, it is capable to identify different walking patterns in patient with osteoarthritis of the lower limbs, whereas the radiology can evaluate the status of the joint’s structures