Characterization of a murine model of monocrotaline pyrrole-induced acute lung injury

<p>Abstract</p> <p>Background</p> <p>New animal models of chronic pulmonary hypertension in mice are needed. The injection of monocrotaline is an established model of pulmonary hypertension in rats. The aim of this study was to establish a murine model of pulmonary hypertension by injection of the active metabolite, monocrotaline pyrrole.</p> <p>Methods</p> <p>Survival studies, computed tomographic scanning, histology, bronchoalveolar lavage were performed, and arterial blood gases and hemodynamics were measured in animals which received an intravenous injection of different doses of monocrotaline pyrrole.</p> <p>Results</p> <p>Monocrotaline pyrrole induced pulmonary hypertension in Sprague Dawley rats. When injected into mice, monocrotaline pyrrole induced dose-dependant mortality in C57Bl6/N and BALB/c mice (dose range 6–15 mg/kg bodyweight). At a dose of 10 mg/kg bodyweight, mice developed a typical early-phase acute lung injury, characterized by lung edema, neutrophil influx, hypoxemia and reduced lung compliance. In the late phase, monocrotaline pyrrole injection resulted in limited lung fibrosis and no obvious pulmonary hypertension.</p> <p>Conclusion</p> <p>Monocrotaline and monocrotaline pyrrole pneumotoxicity substantially differs between the animal species.</p

ISSN: 2454-132X Impact factor: 4.295 Exponential Hfiltering design for discrete-time neural networks switched systems with time-varying delay

Abstract: This paper deals with the exponential H filtering problem for discrete-time neural networks switched singular systems with time-varying delays. The main purpose of this paper is to design a linear mode-dependent filter such that the resulting filtering error system is regular, causal, and exponentially stable with a prescribed H-infinity performance bound. In addition, the decay rate of the filtering error dynamics can also be tuned. By constructing an appropriate Lyapunov functional together with some zero inequalities and using the average dwell time scheme, a novel delay-dependent sufficient condition for the solvability of the H-infinity filtering problem is derived. Based on this condition, the desired filter gains can be obtained by solving a set of linear matrix inequalities (LMIs). A numerical example is presented to show the effectiveness of the proposed design method

Stability and dissipativity analysis for neutral type stochastic Markovian jump static neural networks with time delays

This paper studies the global asymptotic stability and dissipativity problem for a class of neutral type stochastic Markovian Jump Static Neural Networks (NTSMJSNNs) with time-varying delays. By constructing an appropriate Lyapunov-Krasovskii Functional (LKF) with some augmented delay-dependent terms and by using integral inequalities to bound the derivative of the integral terms, some new sufficient conditions have been obtained, which ensure that the global asymptotic stability in the mean square. The results obtained in this paper are expressed in terms of Strict Linear Matrix Inequalities (LMIs), whose feasible solutions can be verified by effective MATLAB LMI control toolbox. Finally, examples and simulations are given to show the validity and advantages of the proposed results

Delay-dependent stability criteria for neutral-type neural networks with interval time-varying delay signals under the effects of leakage delay

Abstract We examine the stability problem for delayed neutral-type neural networks (NNs) with interval time-varying delay signals under the effects of leakage term by constructing a suitable Lyapunov–Krasovskii functionals (LKFs) with the triple- and four-integral terms and using the famous Jensen inequality, Wirtinger single integral inequality (WSII), and Wirtinger double integral inequality (WDII), combined with the reciprocally convex approach (RCC) for the stability of addressing NNs. Therefore, the major contribution of this study lies in a consideration of new integral inequalities and improved LKFs, fully taking the relationship between the terms in the Leibniz–Newton formula within the framework of linear matrix inequalities (LMIs). Moreover, we assume that the lower bound of interval time-varying delay is not restricted to zero. Using several examples, we show that the proposed stability criterion is less conservative than previous results. Also, the proposed technique is applied to benchmark problem that is associated with reasonable issues to showing feasibility on a real-world problem, including transporting time delay signals and leakage delay as a process variable in the quadruple-tank process system

Advantages of collecting multiple urinary iodine concentrations when assessing iodine status of a population

AimTo evaluate the effect of collecting multiple (four) urine samples on the extensive variance often observed within a cohort when determining iodine status via urinary iodine concentration (UIC)

The iodine status of Queensland preschool children after the introduction of mandatory iodine fortification in bread: an exploratory study using a convenience sample

Introduction Appropriate dietary iodine is essential for thyroid hormone synthesis, especially in young children. Following an iodine fortification in bread initiative, approximately 6\ua0% of Australian preschool children were expected to have an excessive iodine status. The aim of this study was to document the current iodine status of preschool children using urinary iodine concentration (UIC) as a biomarker of iodine intake. Methods A convenience sample of fifty-one preschool children, aged 2–3\ua0years, were recruited from south east Queensland. UIC was ascertained from spot morning and afternoon urine samples collected on two consecutive days and food frequency questionnaires were completed for each participant. Dietary iodine intake was extrapolated from UIC assuming 90\ua0% of dietary iodine is excreted in urine and a urine volume of 0.5\ua0L/day. Results A median UIC of 223.3\ua0μg/L was found. The calculated median dietary iodine intake was 124.8\ua0μg/day (SD 47.0) with 9.8\ua0% of samples above the upper level of 200\ua0μg for dietary iodine for children within this age group. No foods were associated with UIC. Discussion Limited by sample size and recruitment strategies, no association was found between usual food intake and UIC. Extrapolated dietary iodine intake indicated that children within this cohort consumed adequate amounts of dietary iodine, although the number of children consuming above the upper limit of 300\ua0μg/day was almost double of expected. The development of a UIC criteria to assess appropriate parameters for varying degrees of iodine status is required for the monitoring of iodine nutrition in this vulnerable age group