Alpha-1 antitrypsin (AAT) augmentation therapy in individuals with the PI*MZ genotype: a pro/con debate on a working hypothesis

Deficiència d'alfa-1 antitripsina; Genotip; Malaltia pulmonarDeficiencia de alfa-1 antitripsina; Genotipo; Enfermedad pulmonarAlpha-1 antitrypsin deficiency; Genotype; Pulmonary diseaseAlpha-1 antitrypsin deficiency (AATD) is a significantly under-diagnosed genetic condition caused by reduced levels and/or functionality of alpha-1 antitrypsin (AAT), predisposing individuals to lung, liver or other systemic diseases. The management of individuals with the PI*MZ genotype, characterized by mild or moderate AAT deficiency, is less clear than of those with the most common severe deficiency genotype (PI*ZZ). Recent genetic data suggest that the PI*MZ genotype may be significantly more prevalent than currently thought. The only specific treatment for lung disease associated with severe AATD is the intravenous infusion of AAT augmentation therapy, which has been shown to slow disease progression in PI*ZZ individuals. There is no specific evidence for the clinical benefit of AAT therapy in PI*MZ individuals, and the risk of emphysema development in this group remains controversial. As such, current guidelines do not support the use of AAT augmentation in PI*MZ individuals. Here, we discuss the limited data on the PI*MZ genotype and offer pro and con perspectives on pursuing an AAT-specific therapeutic strategy in PI*MZ individuals with lung disease. Ultimately, further research to demonstrate the safety, risk/benefit balance and efficacy of AAT therapy in PI*MZ individuals is needed.Medical writing assistance for this manuscript was funded by CSL Behring; the role of the funder was to support medical writing assistance only

Direction of Serbian Trade: Gravity Model Based on Pool Data

The objective of this paper is to evaluate the effects of bilateral trade between Serbia and EUcountries in the period 2001-2015 on the basis of a gravity model. So far in research papers the gravity modelhas been used for the evaluation of effects of trade among different countries. The gravity model, whichcombines the cross-section data and the time-series data, has been estimated to the panel data. Estimatedresults based on a sample of 28 countries reveal that the economic size of foreign countries, the market size oftrading partners (the number of inhabitants), and the geographical distance produce altogether huge effects onSerbia’s total trade and exports. Border and language factors have also been taken into account. The researchleaves room for further scientific analyses and provides guidance for trade policy creators in analyses fordirections of the Serbian trade. This research is based on complex econometric analyses and a recognisedmodel, and shows that there is considerable room for the growth of bilateral trade between Serbia and EU

Fast simulation of a quantum phase transition in an ion-trap realisable unitary map

We demonstrate a method of exploring the quantum critical point of the Ising universality class using unitary maps that have recently been demonstrated in ion trap quantum gates. We reverse the idea with which Feynman conceived quantum computing, and ask whether a realisable simulation corresponds to a physical system. We proceed to show that a specific simulation (a unitary map) is physically equivalent to a Hamiltonian that belongs to the same universality class as the transverse Ising Hamiltonian. We present experimental signatures, and numerical simulation for these in the six-qubit case.Comment: 12 pages, 6 figure

Measurement-Based Teleportation Along Quantum Spin Chains

We consider teleportation of an arbitrary spin-1/2 target quantum state along the ground state of a quantum spin chain. We present a decomposition of the Hilbert space of the many body quantum state into 4 vector spaces. Within each of these subspaces, it is possible to take any superposition of states, and use projective measurements to perform unit fidelity teleportation. Any such superposition is necessarily a spin liquid state. We also show that all total spin-0 quantum states belong in the same space, so that it is possible to perform unit fidelity teleportation over any one-dimensional spin-0 many body quantum state. We generalise to $n$-Bell states, and present some general bounds on fidelity of teleportation given a general state of a quantum spin chain.Comment: 5 pages, 2 figures, presented as posters at "Quantum entanglement in physical and information sciences", Pisa, 2004 and at the AIP Congress, Canberra, 200

Ground state fidelity and quantum phase transitions in free Fermi systems

We compute the fidelity between the ground states of general quadratic fermionic hamiltonians and analyze its connections with quantum phase transitions. Each of these systems is characterized by a $L\times L$ real matrix whose polar decomposition, into a non-negative $\Lambda$ and a unitary $T$, contains all the relevant ground state (GS) information. The boundaries between different regions in the GS phase diagram are given by the points of, possibly asymptotic, singularity of $\Lambda$. This latter in turn implies a critical drop of the fidelity function. We present general results as well as their exemplification by a model of fermions on a totally connected graph.Comment: 4 pages, 2 figure

Entanglement in a periodic quench

We consider a chain of free electrons with periodically switched dimerization and study the entanglement entropy of a segment with the remainder of the system. We show that it evolves in a stepwise manner towards a value proportional to the length of the segment and displays in general slow oscillations. For particular quench periods and full dimerization an explicit solution is given. Relations to equilibrium lattice models are pointed out.Comment: 19 pages, 12 figures, 5 references adde

New Spirometry Indices for Detecting Mild Airflow Obstruction.

The diagnosis of chronic obstructive pulmonary disease (COPD) relies on demonstration of airflow obstruction. Traditional spirometric indices miss a number of subjects with respiratory symptoms or structural lung disease on imaging. We hypothesized that utilizing all data points on the expiratory spirometry curves to assess their shape will improve detection of mild airflow obstruction and structural lung disease. We analyzed spirometry data of 8307 participants enrolled in the COPDGene study, and derived metrics of airflow obstruction based on the shape on the volume-time (Parameter D), and flow-volume curves (Transition Point and Transition Distance). We tested associations of these parameters with CT measures of lung disease, respiratory morbidity, and mortality using regression analyses. There were significant correlations between FEV1/FVC with Parameter D (r = -0.83; p < 0.001), Transition Point (r = 0.69; p < 0.001), and Transition Distance (r = 0.50; p < 0.001). All metrics had significant associations with emphysema, small airway disease, dyspnea, and respiratory-quality of life (p < 0.001). The highest quartile for Parameter D was independently associated with all-cause mortality (adjusted HR 3.22,95% CI 2.42-4.27; p < 0.001) but a substantial number of participants in the highest quartile were categorized as GOLD 0 and 1 by traditional criteria (1.8% and 33.7%). Parameter D identified an additional 9.5% of participants with mild or non-recognized disease as abnormal with greater burden of structural lung disease compared with controls. The data points on the flow-volume and volume-time curves can be used to derive indices of airflow obstruction that identify additional subjects with disease who are deemed to be normal by traditional criteria

Risk factors for severe dental anxiety among medical students

Background/Aim. Severe dental anxiety (SDA) is the most severe form of dental anxiety, thus the aim of this study was to determine the factors associated with SDA in students of health-related disciplines. Methods. In this case-control study the cases were students with severe dental anxiety. The study was conducted at the Faculty of Medical Sciences, University of Kragujevac, Serbia. The participants were undergraduate students attending lectures during spring semester 2010/2011 (n = 1,812). A random sample of 800 students was assessed for the association between various risk factors and the severe dental anxiety. The main outcome measures were the data on demographics, dental anxiety, habits concerning oral hygiene, nutrition, general anxiety and (co)morbidity which were collected from the study participants by semi-structured question questionnaire. Results. Less frequent visits to the dentist (OR adjusted = 7.02 [2.65; 18.60]) and visiting the dentist only when there is a dental problem (OR adjusted = 8.08 [1.28; 50.93]) were associated with severe dental anxiety. The same was true for improper oral hygiene (OR adjusted = 4.25 [1.16; 15.60]). Factors as changing toothbrush more frequently (OR adjusted = 0.33 [0.14; 0.76]) and having chronic disease (OR adjusted = 0.01 [0.00; 0.09]) were inversely associated with severe dental anxiety. The level of education of students was not associated with severe dental anxiety. Conclusion. Inappropriate oral hygiene, less frequent changes of a toothbrush and less frequent visits to the dentist are important risk factors for severe dental anxiety

Phase diagram of a Bose-Fermi mixture in a one-dimensional optical lattice in terms of fidelity and entanglement

We study the ground-state phase diagram of a Bose-Fermi mixture loaded in a one-dimensional optical lattice by computing the ground-state fidelity and quantum entanglement. We find that the fidelity is able to signal quantum phase transitions between the Luttinger liquid phase, the density-wave phase, and the phase separation state of the system; and the concurrence can be used to signal the transition between the density-wave phase and the Ising phase.Comment: 4 pages 3 figure