Alleged Allergy to Penicillin and Isolation Issues: Toward New Practices for French Navy?

INTRODUCTION: According to the literature, 8% of the population claim to have an allergy to penicillin. Allergy tests show that 90% of these patients tolerate this molecule. Physicians working in the French Navy are faced with situations of real isolation and only have a limited number of antibiotics on board, the majority of which are penicillins. They must anticipate the risks linked to the prescription of antibiotics before the mission. However, there is no French recommendation, either military or civilian, intended for general practitioners clarifying the management and allergy assessments of patients alleging a history of allergy to penicillin. This study is the first to evaluate the professional practices of French military practitioners taking care of these patients. The main objective was to evaluate the proportion of sailors who reported an allergy to penicillin and who have never been referred for a consultation with an allergist, by studying the medical files of all the submariners working on the submersible ballistic nuclear submarines squadron in Brest. The secondary objective was to compare these data with the practices of Navy doctors by means of questionnaires. MATERIAL AND METHODS: Our work is composed of two parts: monocentric study of the digital and paper medical files of Brest submariners (n = 814) looking for allergist consultation reports in cases alleging an allergy to penicillin, then comparison with a multicentric collection of all Navy doctors' practices collected by an anonymized questionnaire (n = 37 out of 53 practicing at the time of the study). RESULTS: Forty-seven subjects out of 814 alleged an allergy to penicillin (5.8%). Among them, only 12 (25.5%) had undergone allergy tests, of which 3 (6.4%) were confirmed to be allergic, with no cross-reaction between ß-lactam antibiotics. Yet, according to the questionnaire, 25 doctors (67%) report referring their patients to an allergist and 16 (43%) report having had difficulties at sea in connection with the prescription of antibiotics for these patients. CONCLUSIONS: A study of medical records shows that the allergic risk is not anticipated for 74.5% of patients labeled allergic, despite the difficulties encountered at sea. Standardization of practices within the French Navy is necessary to avoid the prescription of second-line antibiotics, less effective and sometimes unavailable on board, and to improve patient safety in isolation situations. In agreement with French military allergists, we propose, in this article, guidelines for a systematic exploration of allegations of allergy to penicillin in the French Navy.

Complex bifurcation analysis and synchronization optimal control for Hindmarsh-Rose neuron model under magnetic flow effect.

In this contribution, the complex behaviour of the Hindmarsh-Rose neuron model under magnetic flow effect (mHR) is investigated in terms of bifurcation diagrams, Lyapunov exponent plots and time series when varying only the electromagnetic induction strength. Some exciting phenomena are found including, for instance, various firings patterns by applying appropriate magnetic strength and Hopf-fold bursting through fast-slow bifurcation. In addition to this, the interesting phenomenon of Hopf bifurcation is examined in the model. Thus, we prove that Hopf bifurcation occurs in this memristor-based HR neuron model when an appropriately chosen magnetic flux varies and reaches its critical value. Furthermore, one of the main results of this work was the optimal control approach to realize the synchronization of two mHR. The main advantage of the proposed optimal master-slave synchronization from a control point of view is that, in the practical application, the electrical activities (quiescent, bursting, spiking, period and chaos states) of a neuron can be regulated by a pacemaker (master) associated with biological neuron (slave) to treat some diseases such as epilepsy. A suitable electronic circuit is designed and used for the investigations. PSpice based simulation results confirm that the electrical activities and synchronization between coupled neurons can be modulated by electromagnetic flux.

Erratum to: Noise effects on robust synchronization of a small pacemaker neuronal ensemble via nonlinear controller: electronic circuit design.

[This corrects the article DOI: 10.1007/s11571-016-9393-1.].

Noise effects on robust synchronization of a small pacemaker neuronal ensemble via nonlinear controller: electronic circuit design.

In this paper, we report on the synchronization of a pacemaker neuronal ensemble constituted of an AB neuron electrically coupled to two PD neurons. By the virtue of this electrical coupling, they can fire synchronous bursts of action potential. An external master neuron is used to induce to the whole system the desired dynamics, via a nonlinear controller. Such controller is obtained by a combination of sliding mode and feedback control. The proposed controller is able to offset uncertainties in the synchronized systems. We show how noise affects the synchronization of the pacemaker neuronal ensemble, and briefly discuss its potential benefits in our synchronization scheme. An extended Hindmarsh-Rose neuronal model is used to represent a single cell dynamic of the network. Numerical simulations and Pspice implementation of the synchronization scheme are presented. We found that, the proposed controller reduces the stochastic resonance of the network when its gain increases.