Acute nontraumatic general surgical conditions on a combat deployment.

BACKGROUND: Literature is lacking on acute surgical problems that may be encountered on military deployment; even less has been written on whether or not any of these surgical problems could have been avoided with more focused predeployment screening. We sought to determine the burden of illness attributable to acute nontraumatic general surgical problems while on deployment and to identify areas where more rigorous predeployment screening could be implemented to decrease surgical resource use for nontraumatic problems. METHODS: We studied all Canadian Armed Forces (CAF) members deployed to Afghanistan between Feb. 7, 2006, and June 30, 2011, who required treatment for a nontraumatic general surgical condition. RESULTS: During the study period 28 990 CAF personnel deployed to Afghanistan; 373 (1.28%) were repatriated because of disease and 100 (0.34%) developed an acute general surgical condition. Among those who developed an acute surgical illness, 42 were combat personnel (42%) and 58 were support personnel (58%). Urologic diagnoses (n = 34) were the most frequent acute surgical conditions, followed by acute appendicitis (n = 18) and hernias (n = 12). We identified 5 areas where intensified predeployment screening could have potentially decreased the incidence of in-theatre acute surgical illness. CONCLUSION: Our findings suggest that there is a significant acute care surgery element encountered on combat deployment, and surgeons tasked with caring for this population should be prepared to treat these patients.

CONTEXTE: Il y a un manque de données sur les problèmes chirurgicaux aigus qui peuvent survenir lors de déploiements militaires, et encore moins sur la question de savoir si on aurait pu éviter ces problèmes en faisant un dépistage plus ciblé avant le déploiement. Nous avons tenté de déterminer le fardeau de la maladie attribuable à des problèmes non traumatiques aigus de chirurgie générale pendant le déploiement, puis d'identifier les domaines où un dépistage préalable plus rigoureux pourrait être mis en oeuvre pour réduire l'utilisation des ressources chirurgicales pour les problèmes non traumatiques. MÉTHODES: Notre étude a porté sur tous les membres des Forces armées canadiennes (FAC) déployés en Afghanistan entre le 7 février 2006 et le 30 juin 2011 et qui ont eu besoin de traitement pour un état chirurgical général non traumatique. RÉSULTANTS: Pendant la période de l'étude, 28 990 membres des FAC ont été déployés en Afghanistan; 373 (1,28 %) ont été rapatriés en raison de maladie et 100 (0,34 %) ont développé un état chirurgical général aigu. Parmi ces derniers, 42 faisaient partie du personnel de combat (42 %) et 58 faisaient partie du personnel de soutien (58 %). Les diagnostics urologiques (n = 34) constituaient les états chirurgicaux aigus les plus fréquents, suivis de l'appendicite aiguë (n = 18) et des hernies (n = 12). Nous avons identifié 5 domaines où un dépistage intensifié, préalable au déploiement, aurait possiblement réduit l'incidence des états chirurgicaux aigus en théâtre d'opérations. CONCLUSION: Il ressort de nos conclusions que les missions de combat comportent un important élément de soins chirurgicaux aigus et que les chirurgiens chargés de soigner cette population devraient être préparés à traiter ces patients.

[Déterminants du succès d'une démarche provinciale d'usage optimal des antipsychotiques chez les résidents en soins de longue durée selon les acteurs clés impliqués dans l'implantation].

Le Québec présente le taux de prescriptions d'antipsychotiques le plus élevé chez les personnes âgées de 65 ans et plus au Canada. La démarche « Optimiser les pratiques, les usages, les soins et les services - antipsychotiques ¼ (OPUS-AP) vise à pallier cet enjeu. Étant donné ses premiers résultats prometteurs, notre étude visait à identifier les déterminants de son succès. Elle repose sur un devis d'étude de cas regroupant une analyse documentaire et 21 entrevues auprès d'acteurs clés impliqués dans l'implantation. Les résultats mettent en lumière cinq déterminants centraux : 1) une démarche intégrée, collaborative et probante; 2) des communications et des réseaux au service de la démarche; 3) un climat d'implantation favorable aux changements; 4) un engagement et une implication des parties prenantes; et 5) une stratégie d'application des connaissances intégrée et appuyée. Des défis et recommandations pour assurer la pérennisation et la mise à l'échelle d'OPUS-AP et inspirer des démarches similaires sont identifiés.

Optimizing Practices, Use, Care and Services-Antipsychotics (OPUS-AP) in Long-term Care Centers in Québec, Canada: A Strategy for Best Practices.

OBJECTIVES: Antipsychotic medications are often used for the first-line management of behavioral and psychological symptoms of dementia (BPSD) contrary to guideline recommendations. The Optimizing Practices, Use, Care and Services-Antipsychotics (OPUS-AP) strategy aims to improve the well-being of long-term care (LTC) residents with major neurocognitive disorder (MNCD) by implementing a resident-centered approach, nonpharmacologic interventions, and antipsychotic deprescribing in inappropriate indications. DESIGN: Prospective, closed cohort supplemented by a developmental evaluation. SETTING AND PARTICIPANTS: Residents of designated wards in 24 LTC centers in Québec, Canada. METHODS: Provincial guidelines were disseminated, followed by the implementation of an integrated knowledge translation and mobilization strategy, including training, coaching, clinical tools, evaluation of clinical practices, and a change management strategy. Antipsychotic, benzodiazepine, and antidepressant prescriptions; BPSD; and falls were evaluated every 3 months, for 9 months, from January to October 2018. Semistructured interviews (n = 20) were conducted with LTC teams to evaluate the implementation of OPUS-AP. RESULTS: Of 1054 residents, 78.3% had an MNCD diagnosis and 51.7% an antipsychotic prescription. The cohort included 464 residents with both MNCD and antipsychotic prescription. Antipsychotic deprescribing (cessation or dose decrease) was attempted in 220 of the 344 residents still admitted at 9 months. Complete cessation was observed in 116 of these residents (52.7%) and dose reduction in 72 (32.7%), for a total of 188 residents (85.5%; 95% confidence interval: 80.1%, 89.8%). A decrease in benzodiazepine prescriptions and improvements in Cohen-Mansfield Agitation Inventory scores were observed among residents who had their antipsychotics deprescribed. Caregivers and clinicians expressed satisfaction as a result of observing an improved quality of life among residents. CONCLUSIONS AND IMPLICATIONS: Antipsychotic deprescribing was successful in a vast majority of LTC residents with MNCD without worsening of BPSD. Based on this success, phase 2 of OPUS-AP is now under way in 129 LTC centers in Québec.

What do we mean by biological complexity?

The purpose of the present paper is to offer a precise definition of the concepts of integration, emergence and complexity in biological networks through the use of the information theory. If two distinct properties of a network are expressed by two discrete variables, the classical subadditivity principle of Shannon's information theory applies when all the nodes of the network are associated with these properties. If not, the subadditivity principle may not apply. This situation is often to be encountered with enzyme and metabolic networks, for some nodes may well not be associated with these two properties. This is precisely what is occurring with an enzyme that binds randomly its two substrates. This situation implies that an enzyme, or a metabolic network, may display a joint entropy equal, smaller, or larger than the corresponding sum of individual entropies of component sub-systems. In the first case, the collective properties of the network can be reduced to the individual properties of its components. Moreover, the network is devoid of any information. In the second case, the system displays integration effects, behaves as a coherent whole, and has positive information. But if the joint entropy of the network is smaller than the sum of the individual entropies of its components, then the system has emergent collective properties and can be considered complex. Moreover, under these conditions, its information is negative. The extent of negative information is enhanced if the enzyme, or the metabolic network, is far away from equilibrium.

Systems biology and the origins of life? Part I. Are biochemical networks possible ancestors of living systems? Reproduction, identity and sensitivity to signals of biochemical networks.

The set of these two theoretical papers offers an alternative to the hypothesis of a primordial RNA-world. The basic idea of these papers is to consider that the first prebiotic systems could have been networks of catalysed reactions encapsulated by a membrane. In order to test this hypothesis it was attempted to list the main obligatory features of living systems and see whether encapsulated biochemical networks could possibly display these features. The traits of living systems are the following: the ability they have to reproduce; the fact they possess an identity; the fact that biological events should be considered in the context of a history; the fact that living systems are able to evolve by selection of alterations of their structure and self-organization. The aim of these two papers is precisely to show that encapsulated biochemical networks can possess these properties and can be considered good candidates for the first prebiotic systems. In the present paper it is shown that if the proteinoids are not very specific catalysts and if some of the reactions of the network are autocatalytic whereas others are not, the resulting system does not reach a steady-state and tends to duplicate. In the same line, these biochemical networks possess an identity, viz. an information, defined from the probability of occurrence of these nodes. Moreover interaction of two ligands can increase, or decrease, this information. In the first case, the system is defined as emergent, in the second case it is considered integrated. Another property of living systems is that their behaviour is defined in the context of a time-arrow. For instance, they are able to sense whether the intensity of a signal is reached after an increase, or a decrease. This property can be mimicked by a simple physico-chemical system made up of the diffusion of a ligand followed by its chemical transformation catalysed by a proteinoid displaying inhibition by excess substrate. Under these conditions the system reacts differently depending on whether the same ligand concentration is reached after an increase or a decrease.

Systems biology and the origins of life? part II. Are biochemical networks possible ancestors of living systems? networks of catalysed chemical reactions: non-equilibrium, self-organization and evolution.

The present article discusses the possibility that catalysed chemical networks can evolve. Even simple enzyme-catalysed chemical reactions can display this property. The example studied is that of a two-substrate proteinoid, or enzyme, reaction displaying random binding of its substrates A and B. The fundamental property of such a system is to display either emergence or integration depending on the respective values of the probabilities that the enzyme has bound one of its substrate regardless it has bound the other substrate, or, specifically, after it has bound the other substrate. There is emergence of information if p(A)>p(AB) and p(B)>p(BA). Conversely, if p(A)

[Emergence and biological complexity]. / L'émergence et la complexité biologique.

Biological networks possess an organization that expresses their potential information. A function, I(X:Y)N, called mutual information of integration, define, on a quantitative basis, three types of organization. If I(X:Y)N=0, the properties of the global system XY can be reduced to the properties of its component sub-systems X and Y. Hence, XY is not a real system displaying collective properties but the mere collection of X and Y. Its properties are the properties of the sub-systems X and Y. If I(X:Y)N>0, the system is integrated. Although it behaves as a coherent whole, it does not possess many collective properties. Last, if I(X:Y)N<0, the system possesses emergent collective properties and can be considered complex for it possesses many collective properties that cannot be predicted from the independent study of component sub-systems X and Y. In a biological system, the emergence of information usually means the emergence of a novel function. This is probably what is occurring with enzymes. If a protein binds two ligands able to interact, and if the condition above is fulfilled, then the protein behaves as an enzyme able to allow a catalytic reaction between the two reagents.

Reduction, integration and emergence in biochemical networks.

Most studies of molecular cell biology are based upon a process of decomposition of complex biological systems into their components, followed by the study of these components. The aim of the present paper is to discuss, on a physical basis, the internal logic of this process of reduction. The analysis is performed on simple biological systems, namely protein and metabolic networks. A multi-sited protein that binds two ligands x and y can be considered the simplest possible biochemical network. The organization of this network can be described through a comparison of three systems, i.e. XY, X and Y. X and Y are component sub-systems that collect states x(i) and y(j), respectively, i.e. protein states that have bound either i molecules of x (whether or not these states have also bound y), or j molecules of y (whether or not these states have bound x). XY is a system made up of the specific association of X and Y that collects states x(i)y(j). One can define mean self-informations per node of the network, , and . Reduction of the system XY into its components is possible if, and only if, ,is equal to the sum of and . If is smaller than the sum of and , the system is integrated, for it has less self-information than the set of its components X and Y. It can also occur that , be larger than the sum of and . Hence, the system XY displays negative integration and emergence of self-information relative to its components X and Y. Such a system is defined as complex. Positive or negative integration of the system implies it cannot be reduced to its components. The degree of integration can be measured by a function , called mutual information of integration. In the case of enzyme networks, emergence of self-information is associated with emergence of catalytic activity. Moreover, if the enzyme reaction is part of a metabolic sequence, its mutual information of integration can be increased by an effect of context of this sequence.