Malaria transmission in two localities in north-western Argentina

<p>Abstract</p> <p>Background</p> <p>Malaria is one of the most important tropical diseases that affects people globally. The influence of environmental conditions in the patterns of temporal distribution of malaria vectors and the disease has been studied in different countries. In the present study, ecological aspects of the malaria vector <it>Anopheles </it>(<it>Anopheles</it>) <it>pseudopunctipennis </it>and their relationship with climatic variables, as well as the seasonality of malaria cases, were studied in two localities, El Oculto and Aguas Blancas, in north-western Argentina.</p> <p>Methods</p> <p>The fluctuation of <it>An. pseudopunctipennis </it>and the malaria cases distribution was analysed with Random Effect Poisson Regression. This analysis takes into account the effect of each climatic variable on the abundance of both vector and malaria cases, giving as results predicted values named Incidence Rate Radio.</p> <p>Results</p> <p>The number of specimens collected in El Oculto and Aguas Blancas was 4224 (88.07%) and 572 (11.93%), respectively. In El Oculto no marked seasonality was found, different from Aguas Blancas, where high abundance was detected at the end of spring and the beginning of summer. The maximum mean temperature affected the <it>An. pseudopunctipennis </it>fluctuation in El Oculto and Aguas Blancas. When considering the relationship between the number of malaria cases and the climatic variables in El Oculto, maximum mean temperature and accumulated rainfall were significant, in contrast with Aguas Blancas, where mean temperature and humidity showed a closer relationship to the fluctuation in the disease.</p> <p>Conclusion</p> <p>The temporal distribution patterns of <it>An. pseudopunctipennis </it>vary in both localities, but spring appears as the season with better conditions for mosquito development. Maximum mean temperature was the most important variable in both localities. Malaria cases were influenced by the maximum mean temperature in El Oculto, while the mean temperature and humidity were significant in Aguas Blancas. In Aguas Blancas peaks of mosquito abundance and three months later, peaks of malaria cases were observed. The study reported here will help to increase knowledge about not only vectors and malaria seasonality but also their relationships with the climatic variables that influence their appearances and abundances.</p

Estudio comparativo entre banda de tensión y tornillo compresivo para la artrodesis interfalángica proximal y metacarpofalángica

Resumen Introducción: Los métodos más utilizados para la artrodesis de la articulación interfalángica proximal y metacarpofalángica son la banda de tensión y el tornillo compresivo. El objetivo de este estudio fue comparar los resultados entre pacientes tratados con estas técnicas. Materiales y Métodos: Estudio comparativo retrospectivo de 10 años. Se incluyeron pacientes esqueléticamente maduros tratados por artrosis y artritis. Se analizaron la tasa de consolidación ósea, el tiempo hasta la consolidación, la incidencia de complicaciones y la tasa de reoperaciones. En un análisis secundario, se compararon los pacientes reumáticos y no reumáticos. Resultados: Se evaluaron 56 casos en 44 pacientes (edad promedio 53 años). Grupo 1: 35 casos tratados con banda de tensión y grupo 2: 21 tratados con tornillo compresivo. Había 32 casos reumáticos y 24 no reumáticos. El seguimiento promedio fue de 24 meses. La tasa promedio de consolidación fue del 94,2% en el grupo 1 y del 85,7% en el grupo 2. La incidencia de complicaciones fue del 11,4% en el primer grupo y 23,8% en el segundo, y la tasa de reoperaciones, del 17,1% y del 0%, respectivamente. Conclusiones: Ambos métodos permiten lograr tasas altas de consolidación, pero la incidencia de seudoartrosis fue casi tres veces superior con el tornillo compresivo que con la banda de tensión. La tasa más alta de reoperaciones en el grupo con banda de tensión fue por extracción del material. El tiempo de consolidación fue más corto en los pacientes no reumáticos, independientemente de la técnica. Palabras clave: Artrodesis; fusión interfalángica proximal y metacarpofalángica; banda de tensión; tornillo compresivo. Nivel de Evidencia: II

Feasibility, drug safety, and effectiveness of etiological treatment programs for Chagas disease in Honduras, Guatemala, and Bolivia: 10-year experience of Médecins Sans Frontières

BACKGROUND: Chagas disease (American trypanosomiasis) is a zoonotic or anthropozoonotic disease caused by the parasite Trypanosoma cruzi. Predominantly affecting populations in poor areas of Latin America, medical care for this neglected disease is often lacking. Médecins Sans Frontières/Doctors Without Borders (MSF) has provided diagnostic and treatment services for Chagas disease since 1999. This report describes 10 years of field experience in four MSF programs in Honduras, Guatemala, and Bolivia, focusing on feasibility protocols, safety of drug therapy, and treatment effectiveness. METHODOLOGY: From 1999 to 2008, MSF provided free diagnosis, etiological treatment, and follow-up care for patients <18 years of age seropositive for T. cruzi in Yoro, Honduras (1999-2002); Olopa, Guatemala (2003-2006); Entre Ríos, Bolivia (2002-2006); and Sucre, Bolivia (2005-2008). Essential program components guaranteeing feasibility of implementation were information, education, and communication (IEC) at the community and family level; vector control; health staff training; screening and diagnosis; treatment and compliance, including family-based strategies for early detection of adverse events; and logistics. Chagas disease diagnosis was confirmed by testing blood samples using two different diagnostic tests. T. cruzi-positive patients were treated with benznidazole as first-line treatment, with appropriate counseling, consent, and active participation from parents or guardians for daily administration of the drug, early detection of adverse events, and treatment withdrawal, when necessary. Weekly follow-up was conducted, with adverse events recorded to assess drug safety. Evaluations of serological conversion were carried out to measure treatment effectiveness. Vector control, entomological surveillance, and health education activities were carried out in all projects with close interaction with national and regional programs. RESULTS: Total numbers of children and adolescents tested for T. cruzi in Yoro, Olopa, Entre Ríos, and Sucre were 24,471, 8,927, 7,613, and 19,400, respectively. Of these, 232 (0.9%), 124 (1.4%), 1,475 (19.4%), and 1,145 (5.9%) patients, respectively, were diagnosed as seropositive. Patients were treated with benznidazole, and early findings of seroconversion varied widely between the Central and South American programs: 87.1% and 58.1% at 18 months post-treatment in Yoro and Olopa, respectively; 5.4% by up to 60 months in Entre Ríos; and 0% at an average of 18 months in Sucre. Benznidazole-related adverse events were observed in 50.2% and 50.8% of all patients treated in Yoro and Olopa, respectively, and 25.6% and 37.9% of patients in Entre Ríos and Sucre, respectively. Most adverse events were mild and manageable. No deaths occurred in the treatment population. CONCLUSIONS: These results demonstrate the feasibility of implementing Chagas disease diagnosis and treatment programs in resource-limited settings, including remote rural areas, while addressing the limitations associated with drug-related adverse events. The variability in apparent treatment effectiveness may reflect differences in patient and parasite populations, and illustrates the limitations of current treatments and measures of efficacy. New treatments with improved safety profiles, pediatric formulations of existing and new drugs, and a faster, reliable test of cure are all urgently needed

Dedo azul agudo idiopático no isquémico: síndrome de Achenbach. Presentación de un caso y revisión bibliográfica

El síndrome de Achenbach es un cuadro de baja incidencia y de etiología idiopática. Se caracteriza por la aparición aguda de coloración azul digital sin un episodio desencadenante, imitando a un cuadro isquémico, pero, al contrario, el síndrome de Achenbach se autolimita sin dejar secuelas. Se presenta una mujer de 75 años que consultó en la central de emergencias por dolor y cambio de coloración violácea del dedo índice de su mano derecha, de inicio súbito. Los estudios complementarios no aportaron información relevante. Se administró un tratamiento sintomático y se logró la resolución completa del cuadro. La anamnesis y el examen físico exhaustivo tienen un rol fundamental para sospechar este cuadro y los estudios complementarios se reservan para descartar otras enfermedades, si es necesario. Consideramos que conocer esta enfermedad y un abordaje correcto conducen a un diagnóstico apropiado

REINFORCED LEARNING OF CONTEXT MODELS FOR UBIQUITOUS COMPUTING. Application to a ubiquitous personal assistant

International audienceUbiquitous environments may become a reality in a foreseeable future and research is aimed on making them more and more adapted and comfortable for users. Our work consists on applying reinforcement learning techniques in order to adapt services provided by a ubiquitous assistant to the user. The learning produces a context model, associating actions to perceived situations of the user. Associations are based on feedback given by the user as a reaction to the behavior of the assistant. Our method brings a solution to some of the problems encountered when applying reinforcement learning to systems where the user is in the loop. For instance, the behavior of the system is completely incoherent at the beginning and needs time to converge. The user does not accept to wait that long to train the system. The user's habits may change over time and the assistant needs to integrate these changes quickly. We study methods to accelerate the reinforced learning process

An architecture for ubiquitous applications

International audienceThis paper proposes a framework intended to help developers to create ubiquitous applications. We argue that context is a key concept in ubiquitous computing and that, by nature, a ubiquitous application is distributed and needs to be easily deployable. Thus we propose an easy way to build applications made of numerous modules spread in the environment and interconnected. This network of modules forms a permanently running system. The control (installation, update, etc.) of such a module is obtained by a simple, possibly remote, command and without requiring to stop the whole system. We ourselves used this architecture to create a ubiquitous application, which we present here as an illustration

Apprentissage par renforcement de modèles de contexte pour l'informatique ambiante

Cette thèse étudie l'acquisition automatique par apprentissage d'un modèle de contexte pour un utilisateur dans un environnement ubiquitaire. Dans un tel environnement, les dispositifs peuvent communiquer et coopérer afin de former un espace informatique cohérent. Certains appareils ont des capacités de perception, utilisées par l'environnement pour détecter la situation - le contexte - de l'utilisateur. D'autres appareils sont capables d'exécuter des actions. La problématique que nous nous sommes posée est de déterminer les associations optimales pour un utilisateur donné entre les situations et les actions. L'apprentissage apparaît comme une bonne approche car il permet de personnaliser l'environnement sans spécification explicite de la part de l'usager. Un apprentissage à vie permet, par ailleurs, de toujours s'adapter aux modifications du monde et des préférences utilisateur. L'apprentissage par renforcement est un paradigme d'apprentissage qui peut être une solution à notre problème, à condition de l'adapter aux contraintes liées à notre cadre d'application.This thesis studies the automatic acquisition by machine learning of a context model for a user in a ubiquitous environment. In such an environment, devices can communicate and cooperate in order to create a consistent computerized space. Some devices possess perceptual capabilities. The environment uses them to detect the user's situation his context. Other devices are able to execute actions. Our problematics consists in determining the optimal associations, for a given user, between situations and actions. Machine learning seems to be a sound approach since it results in a customized environment without requiring an explicit specification from the user. A life long learning lets the environment adapt itself continuously to world changes and user preferences changes. Reinforcement learning can be a solution to this problem, as long as it is adapted to some particular constraints due to our application setting.GRENOBLE1-BU Sciences (384212103) / SudocSudocFranceF

An Architecture for Ubiquitous Applications

Abstract. This paper proposes a framework intended to help developers to create ubiquitous applications. We argue that context is a key concept in ubiquitous computing and that, by nature, a ubiquitous application is distributed and needs to be easily deployable. Thus we propose an easy way to build applications made of numerous modules spread in the environment and interconnected. This network of modules forms a permanently running system. The control (installation, update, etc.) of such a module is obtained by a simple, possibly remote, command and without requiring to stop the whole system. We ourselves used this architecture to create a ubiquitous application, which we present here as an illustration. 1

Reinforcement Learning of Context Models for a Ubiquitous Personal Assistant

Summary. Ubiquitous environments may become a reality in a foreseeable future and research is aimed on making them more and more adapted and comfortable for users. Our work consists on applying reinforcement learning techniques in order to adapt services provided by a ubiquitous assistant to the user. The learning produces a context model, associating actions to perceived situations of the user. Associations are based on feedback given by the user as a reaction to the behavior of the assistant. Our method brings a solution to some of the problems encountered when applying reinforcement learning to systems where the user is in the loop. For instance, the behavior of the system is completely incoherent at the be-ginning and needs time to converge. The user does not accept to wait that long to train the system. The user’s habits may change over time and the assistant needs to integrate these changes quickly. We study methods to accelerate the reinforced learning process.