Randomized Clinical Trial on Ivermectin versus Thiabendazole for the Treatment of Strongyloidiasis

Strongyloidiasis is the infection caused by the worm Strongyloides stercoralis. Due to its peculiar life cycle Strongyloides may remain indefinitely in the host, if not effectively cured. Although the disease is usually mild, in case of weakening of the host's immune defenses the worm may invade virtually all organs and tissues (disseminated strongyloidiasis, almost invariably fatal). The treatment must then reach the goal of the complete elimination of the parasite. Small size clinical trials showed similar, high efficacy of the two drugs ivermectin (used as a single dose) and thiabendazole (used twice daily for two consecutive days). All trials used as the criterion for cure the absence of larvae in stool exams. The latter however may easily miss the infection, falsely suggesting that the infection has been cured. This trial, using a test detecting specific Strongyloides antibodies as an additional and more sensitive diagnostic tool, confirms previous reports: the two drugs have similar efficacy but ivermectin is better tolerated and is therefore the first choice. However the cure rate was lower than 70% for the standard, single dose. The authors then conclude that a larger, multi center trial is needed to find the optimal dose schedule of ivermectin

A Research Agenda for Helminth Diseases of Humans: Social Ecology, Environmental Determinants, and Health Systems

In this paper, the Disease Reference Group on Helminth Infections (DRG4), established in 2009 by the Special Programme for Research and Training in Tropical Diseases (TDR), with the mandate to review helminthiases research and identify research priorities and gaps, focuses on the environmental, social, behavioural, and political determinants of human helminth infections and outlines a research and development agenda for the socioeconomic and health systems research required for the development of sustainable control programmes. Using Stockols' social-ecological approach, we describe the role of various social (poverty, policy, stigma, culture, and migration) and environmental determinants (the home environment, water resources development, and climate change) in the perpetuation of helminthic diseases, as well as their impact as contextual factors on health promotion interventions through both the regular and community-based health systems. We examine these interactions in regard to community participation, intersectoral collaboration, gender, and possibilities for upscaling helminthic disease control and elimination programmes within the context of integrated and interdisciplinary approaches. The research agenda summarises major gaps that need to be addressed

Efecto de adultos en el establecimiento de juveniles de Calomys musculinus (Rodentia: Sigmodontinae)

Bajo la hipótesis de que en poblaciones de clausura los individuos reproductivamente activos de Calomys musculinus excluyen juveniles de su mismo sexo, se probaron las siguientes predicciones: 1) el grado de solapamiento entre áreas de acción (AA) de adultos y juveniles del mismo sexo será menor que aquel registrado entre adultos y juveniles del sexo opuesto; 2) los juveniles se establecerán fuera del AA de adultos de su mismo sexo. Nuestros resultados apoyaron parcialmente la hipótesis, el efecto sexo-específico de adultos reproductivamente activos quedó de manifiesto en el establecimiento de machos juveniles respecto al AA de adultos de su mismo sexo.Effect of adults in the establishment of juvenile Calomys musculinus (Rodentia: Sigmodontinae). Under the hypothesis that in enclosure populations reproductively active individuals of Calomys musculinus exclude juveniles of the same sex, we test the predictions that: 1) home range overlap degree is lower between adults and juveniles of the same sex; 2) juveniles do not establish within the home range of adults of their same sex. Our results partially support the hypothesis; although reproductively active adults affected the establishment of juveniles, this effect was clearly sex-specific as regards the spatial location of juvenile in relation to adult male home ranges.Fil: Austrich, Ailin. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Steinmann, Andrea Rosa. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bonatto, Maria Florencia. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gomez, Maria Daniela. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Demographic response to the manipulation of adult females in corn mouse populations

La variación del tamaño de una población obedece a cambios en parámetros demográficos tales como sobrevida y reclutamiento. Estos parámetros demográficos pueden estar afectados por la competencia intraespecífica, de modo que los adultos pueden desempeñar un papel importante en la sobrevida y/o la reproducción de los juveniles en muchas especies de mamíferos pequeños. Estudiamos una población de Calomys musculinus utilizando modelos de captura-marcado-recaptura para evaluar el efecto de la remoción de hembras sobre la demografía de la población. El estudio se realizó en cuatro clausuras durante dos períodos: período de referencia y de tratamiento. El período de referencia permitió describir la demografía poblacional sin manipulación mientras que el período de tratamiento evaluó la remoción de hembras. Se realizaron siete sesiones de trampeo mensuales entre primavera y otoño. Se estimaron la sobrevida aparente, el reclutamiento, la tasa de crecimiento poblacional y la probabilidad de recaptura. Los modelos fueron construidos con dichos parámetros restringidos a variar como función del tiempo, la clausura, el sexo y/o el tratamiento. Durante el período de referencia la sobrevida fue mayor en hembras y disminuyó hacia el mes de junio; el reclutamiento mostró un pico en febrero con un mayor número de machos reclutados; la tasa de crecimiento poblacional mostró un pico en febrero y disminuyó hacia junio. Durante el período de tratamiento la sobrevida fue mayor al comienzo del período reproductivo disminuyendo posteriormente y el reclutamiento fue mayor en los controles que en los tratamientos sin hembras; la tasa de crecimiento mostró un patrón similar al del período de referencia. La remoción de hembras no afectó las tasas de crecimiento ni el tamaño poblacional. Bajo nuestras condiciones experimentales y metodológicas, los resultados indicarían que la ausencia de hembras en las clausuras experimentales no fue suficiente para causar un efecto claro en el tamaño final de la población.Variation in population abundance is a consequence of changes in demographic parameters such as survival and recruitment. These demographic parameters can be affected by intraspecific competition, thus adults may play an important role influencing the survival and/or reproduction of juvenile individuals in many species of small mammals. We present an analysis of Calomys musculinus populations using capturemark- recapture models in order to evaluate the effect of female removal on their demography. The study was carried out in four enclosures during two different periods: a reference period and a treatment period, with the removal of adult females. Reference period was analyzed to describe population demography without manipulations. In treatment period, two control enclosures maintained both parents remained with their offspring whereas other two enclosures had their adult females removed. Seven monthly trapping sessions were carried out (spring to autumn). We estimated apparent survival, recruitment, population growth rates and recapture probabilities. Models considered these parameters constrained to vary as a function of time, enclosure, sex and/or treatment. During the reference period survival and recruitment showed sex and time effects, survival was higher in females and decreased towards June; recruitment showed a peak in February with a higher number of recruited males; population growth rates peaked in February and decreased towards June. During the treatment period survival showed time effect whereas recruitment showed time and treatment effects. Survival was higher at the beginning of the breeding period and decreased afterwards, and recruitment was higher in control enclosures; population growth rates showed a similar pattern than in reference period. There were not differences in growth rates and abundances between control and experimental enclosures. Under our experimental and methodological conditions, the results would indicate that the absence of females in experimental enclosures was not enough to cause a clear impact on final population size

Designing mobile systems in highly dynamic scenarios : the WORKPAD methodology

The design of interactive systems to be used in mobile and pervasive scenarios, such as emergency management, requires novel methodologies which combine user-centred design approaches and software engineering approaches tailored for distributed architectures. In this paper, the methodology adopted in a successful research project is presented together with a case study. Keywords: User-centred design - Requirement collection - Interaction design - Emergency scenarios - Mobile systems

Small mammal dispersal in intensively managed agroecosystems : Calomys venustus as a model

Context: Dispersal and gene flow are key processes for the persistence of populations through the maintenance of large effective sizes and recolonization of empty patches. Therefore, assessing how dispersal is modulated by landscape characteristics and the species’ perception of them is are crucial in a context of anthropogenic landscape change and habitat fragmentation. Objectives: We used the rodent Calomys venustus as a model to study genetic connectivity in highly transformed agricultural landscape, to understand how species cope with changes in human modified environments. Methods: We placed sixty five trap lines within an area of approximately 1500 km2 in an agroecosystem in central Argentina, separated by different landscape elements (crop fields, dirt roads, paved roads, and water streams). To assess their influence on dispersal, we implemented two Bayesian clustering methods, and several methodologies based on the pattern of genetic similarity between pairs of individuals relative to their geographic separation. Results: Genetic autocorrelation analysis showed a clinal pattern, with a genetic patch size of approximately 4 km. Bayesian clustering suggested the presence of 7 randomly mating populations with highly variable geographic extent that followed an isolation by distance pattern. Their boundaries did not coincide with any apparent barrier to dispersal. An Estimated Effective Migration Surfaces analysis confirmed that dispersal in this species would not be impeded by landscape features. Conclusions: The strong habitat preferences of C. venustus would not be related to dispersion. Population limits were not defined by apparent barriers to gene flow. We propose that the perceived range of landscape complexity in C. venustus and the grain of resources at particular sites in the landscape would determine the boundaries of genetic clusters.2023-05Fil: Chiappero, Marina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Diversidad y Ecología Animal; Argentina.Fil: Chiappero, Marina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Genética de Poblaciones y Evolución; Argentina.Fil: Vera, Noelia S. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Genética de Poblaciones y Evolución; Argentina.Fil: Sommaro, Lucía V. Universidad Nacional de Jujuy; Argentina.Fil: Sommaro, Lucia V. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ecorregiones Andinas. Laboratorio de Ecología Evolutiva y Biogeografía; Argentina.Fil: Simone, Ivana. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Físico-Químicas y Naturales. Orientación de Genética General; Argentina.Fil: Steinmann, Andrea R. Universidad Nacional de Río Cuarto; Argentina.Fil: Steinmann, Andrea R. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra, Biodiversidad y Sustentabilidad Ambiental. Grupo de Investigaciones en Ecología Poblacional y Comportamental; Argentina.Fil: Gardenal, Cristina N. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina.Fil: Gardenal, Crstina N. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Diversidad y Ecología Animal; Argentina.Fil: Priotto, José W. Universidad Nacional de Río Cuarto; Argentina.Fil: Priotto, José W. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra, Biodiversidad y Sustentabilidad Ambiental. Grupo de Investigaciones en Ecología Poblacional y Comportamental; Argentina

Multiple paternity in a wild population of the corn mouse: its potential adaptive significance for females

Mating with multiple males within a single reproductive event is a common female mating strategy in mice and voles, but its adaptive function is often unclear. In this study, we used 7 microsatellite loci to investigate if multiple paternity occurs in wild populations of the socially promiscuous Calomys musculinus. We also analyzed if multiple paternity increases litter size and/or genetic variability among offspring. In addition, we examined if multiple paternity occurs more frequently in litters conceived at high population density than those conceived at low population density. By genotyping 23 females and their 135 embryos (5.9 ± 1.6 SE pups per female), we found that 56.5% of the litters were sired by 2 or 3 males. We found no association between multiple paternity, litter size, and genetic variability. In addition, multiple paternity did not vary in relation to population density. Our results provide clear evidence of multiple paternity and offer the first genetic documentation of mating systems in mice in Argentina. We discuss the extent of multiple paternity in relation to potential adaptive strategies in female corn mouse.Fil: Sommaro, Lucía Valeria. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Fisiología. Cátedra de Genética de Poblaciones y Evolución; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Chiappero, Marina Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; Argentina. Universidad Nacional de Córdoba. Facultad de Cs.exactas Físicas y Naturales. Cátedra de Genética de Poblaciones y Evolución; ArgentinaFil: Vera, Noelia Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; Argentina. Universidad Nacional de Córdoba. Facultad de Cs.exactas Físicas y Naturales. Cátedra de Genética de Poblaciones y Evolución; ArgentinaFil: Coda, José Antonio. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Priotto, Jose Waldemar. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Steinmann, Andrea Rosa. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentin