Helminth communities and host-parasite relationships in argentine brown rat (Rattus norvegicus)

The aims of this research were: 1) to determine the helminth parasite fauna of seventy two Rattus norvegicus (Berkenhout, 1769) individuals inhabiting poultry farms in the Pampean region of Argentina; 2) to examine the relationship between parasitism and individual characteristics of the hosts, and 3) to analyze the associations among helminths. The study was carried out in twenty-four poultry farms from autumn 2000 to winter 2001. Nematodes were found in the intestine or caecum rectum of the 74 % of rats and cestodes were found along all the intestine of the 28 % of rats. Heterakis spumosa (Travassos 1914) was a central species, whereas Syphacia muris, Yamaguti 1941, Nippostrongylus brasiliensis (Travassos 1914) and Hymenolepis diminuta (Rudolphi 1819) were satellite species. Helminths do not affect rat survival and growth of rats. Rats parasitized with H. spumosa and H. diminuta were larger and older than non-parasitized rats. The intensity of infection with H. spumosa significantly increased with rat age. Rats parasitized with Nippostrongylus brasiliensis and Syphacia muris did not differ in size and age with respect to non-parasitized ones. The mean intensity of infections per host was 33.74, 74.28, higher than 200, and 3.10 for H. spumosa, S. muris, N. brasiliensis and H. diminuta, respectively. The mean intensity of infection with H. spumosa was higher in summer than in the other seasons, while the higher mean intensity of infection with N. brasiliensis and S. muris occurred in autumn. Infections with Heterakis spumosa and Syphacia muris, and with Syphacia muris and Nippostrongylus brasiliensis were independent; while Heterakis spumosa and Nippostrongylus brasiliensis were negatively associated.Centro de Estudios Parasitológicos y de VectoresFacultad de Ciencias Naturales y Muse

Helminth communities and host-parasite relationships in argentine brown rat (Rattus norvegicus)

The aims of this research were: 1) to determine the helminth parasite fauna of seventy two Rattus norvegicus (Berkenhout, 1769) individuals inhabiting poultry farms in the Pampean region of Argentina; 2) to examine the relationship between parasitism and individual characteristics of the hosts, and 3) to analyze the associations among helminths. The study was carried out in twenty-four poultry farms from autumn 2000 to winter 2001. Nematodes were found in the intestine or caecum rectum of the 74 % of rats and cestodes were found along all the intestine of the 28 % of rats. Heterakis spumosa (Travassos 1914) was a central species, whereas Syphacia muris, Yamaguti 1941, Nippostrongylus brasiliensis (Travassos 1914) and Hymenolepis diminuta (Rudolphi 1819) were satellite species. Helminths do not affect rat survival and growth of rats. Rats parasitized with H. spumosa and H. diminuta were larger and older than non-parasitized rats. The intensity of infection with H. spumosa significantly increased with rat age. Rats parasitized with Nippostrongylus brasiliensis and Syphacia muris did not differ in size and age with respect to non-parasitized ones. The mean intensity of infections per host was 33.74, 74.28, higher than 200, and 3.10 for H. spumosa, S. muris, N. brasiliensis and H. diminuta, respectively. The mean intensity of infection with H. spumosa was higher in summer than in the other seasons, while the higher mean intensity of infection with N. brasiliensis and S. muris occurred in autumn. Infections with Heterakis spumosa and Syphacia muris, and with Syphacia muris and Nippostrongylus brasiliensis were independent; while Heterakis spumosa and Nippostrongylus brasiliensis were negatively associated.Centro de Estudios Parasitológicos y de VectoresFacultad de Ciencias Naturales y Muse

Capítulo VII: variabilidad genética y ambiental entre líneas de tomate "chonto", Lycopersicon esculentum Mill, sin utilizar pruebas de progenie

&lt;p&gt;This paper reports the results of a study on genetic and environmental variability between 43 lines of "Chonto" tomato, Lycopersicon esculentum Mill, without using progeny offspring test. The experimental material were planted under field conditions using three randomized blocks. Data on individual plants were recorded for yield/plant, number of fruit/plant, average fruit weight, number of inflorescences/plant, number of fruits/inflorescence, number of locules/fruit, average locule weight, fruit shape index, pericarp thickness, days to flowering, harvest lenght, plant heigh, first inflorescence heigh, internode lenght, reaction to the presence of Scrobipalpula absoluta and Xanthomonas vesicatoria. The quantitative characters were subjeted to variance analysis in orden to evaluate the genetic and environmental variation. Heritability in the wide sense, genetic variability coeficient and the expected progress by selection were estimated. Fenotipic, environmental and genetic correlations among some evaluated characters were also carried out. Important  genotipic differences, at 1% of probability, for the evaluated characters were found. Generally, in the most of the evaluated characters the largest contribution of the total variation correspond to the genetic variation. The contribution of the environmental variation was very low.&lt;/p&gt;<br>&lt;p&gt;Con el fin de analizar la variabilidad genética y ambiental, de algunos caracteres agronómicos importantes en tomate "chonto" se evaluaron 43 líneas, en condiciones de campo utilizando un diseño experimental de bloques al azar con tres repeticiones. Los datos experimentales se obtuvieron a partir de tres plantas individuales por repetición y en plena competencia. Se evaluaron los siguientes caracteres cuantitativos: producción por planta, número de frutos por planta, peso promedio de frutos, número de inflorescencias por planta, número de frutos por inflorescencias, número de lóculos por fruto, peso promedio de lóculos, formato de fruto, grosor de pericarpio, días a primera flor abierta, duración de la cosecha, altura de la planta en el momento de la cosecha, altura de la primera inflorescencia y longitud del primer entrenudo. Se realizó el análisis de varianza con miras a evaluar la varianza genética y la varianza ambiental, heredabilidad en el sentido amplio, coeficiente de varianza genética y progreso esperado por selección. También se efectuaron correlaciones fenotípicas, genotípicas y ambientales entre algunos caracteres evaluados. Se encontraron diferencias genotípicas al 1% de probabilidad, para todos los caracteres evaluados. Para la mayoría de los caracteres evaluados, la varianza genética obtuvo mayor contribución a la varianza fenotípica. El aporte de la varianza ambiental fue muy bajo.&lt;/p&gt

Efecto del aceite de chía en el perfil proteico de homogenato de hígado durante la exposición a bajas dosis de cadmio en un modelo de rata wistar

Dispositivos electrónicos en desuso incrementan los niveles de cadmio (Cd) en el ambiente constituyendo un riesgo para la salud pública. Paralelamente, se ha informado que el aceite de chía (chía) beneficia la salud. En estudios previos demostramos disminución de la expresión de proteínas totales en hígado de ratas tratadas con 10 mg/kg CdCl 2 . Sin embargo, no existen estudios sobre efectos de chía en estas alteraciones. El objetivo fue evaluar cuali y cuantitativamente el perfil proteico y la expresión de enzimas del tipo esterasas en homogenatos hepáticos. Ratas Wistar fueron divididas en: Grupo A se administró por vía oral agua destilada 1 dosis diaria 5 veces por semana por 60 días. Grupo B10 mg/kg CdCl₂, por la misma vía y período. Grupo C 240 μl/kg chía por la misma vía y período. Grupo D se coadministró Cd/chía en la misma dosis, vía y período. Grupo E se coadministró Cd/chía en la misma dosis y vía por 30 días y luego agua destilada por 30 días. Grupo F se coadministró Cd/chía en la misma dosis y vía por 30 días y luego chía por 30 días. El contenido proteico del homogenato hepático fue evaluado por corridas electroforéticas en geles de poliacrilamida nativos teñidos con plata. Se evaluó actividad de tipo esterasa en zimogramas teñidos con α-naftil acetato y Fast Blue. El software GelAnalyzer se utilizó para la cuantificación de proteínas. Los resultados evidenciaron que la exposición al Cd provocó disminución de la expresión de enzimas con actividad esterasa (Grupos B vs A). Chía incremento la expresión de la banda con actividad esterasa (GruposC vs B). La coadministración Cd/chía evitó que la exposición al Cd induzca disminución de la expresión de enzimas con actividad esterasa (Grupos D, E y F vs B). Estos resultados indican que la administración de chía podría minimizar las alteraciones causada por el Cd.Disused electronic devices increase levels of the cadmium (Cd) in the environment constituting a public health risk. In parallel, chia oil has been reported to benefit health. Previous studies in rats showed decreased expression of total proteins in liver with Cd2+ treatment. However, until now has not been described the effects of chia oil on these alterations. The aim of this work was to evaluate the protein expression and esterase activity in liver homogenates qualitatively and quantitatively. Wistar rats were divided into: Group A: distilled water was administered orally, 1 dose daily 5 times per week and for 60 days. Group B: 10 mg/kg CdCl2, for the same period and period. Group C: 240 μl/kg chia oil by the same route and period. Group D: CdCl2 and chia oil were coadministered at doses previously reported by the same route and period. Group E: CdCl2 and chia oil were coadministered in these doses by the same route for 30 days and then distilled water for 30 days. Group F: dry gave CdCl2 and chia oil at doses previously reported by the same route for 30 days and then chia oil for 30 days. Native polyacrylamide gel (PAGE) electrophoresis of liver homogenates proteins was using silver staining. The zymogram with esterase activity was evaluated with 1-naphtyl-acetate and Fast Blue. The GelAnalyzer software was used for the quantification of the protein concentration. The results showed that the exposure to Cd caused a decrease in the expression of enzymes with esterase activity (Groups B vs A). Chia oil increased expression of the band with esterase activity (Groups C vs B). Co-administration of Cd/chia oil prevented Cd exposure from inducing decreased expression of enzymes with esterase activity (Groups D, E and F vs. B). These results indicate that administration of chia oil could minimize the changes caused by Cd.Fil: González, Maria Elina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Romero, Cintia Mariana. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Taboada, Luis Nicolás. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Villafañe, M.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Medina, Marcela Fatima. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaXXXIV Jornadas Científicas de la Asociación de Biología de Tucumán.Tafí ViejoArgentinaAsociación de Biología de Tucumá

Multiple interacting environmental drivers reduce the impact of solar UVR on primary productivity in Mediterranean lakes

Increases in rainfall, continental runoff, and atmospheric dust deposition are reducing water transparency in lakes worldwide (i.e. higher attenuation Kd). Also, ongoing alterations in multiple environmental drivers due to global change are unpredictably impacting phytoplankton responses and lakes functioning. Although both issues demand urgent research, it remains untested how the interplay between Kd and multiple interacting drivers affect primary productivity (Pc). We manipulated four environmental drivers in an in situ experiment—quality of solar ultraviolet radiation (UVR), nutrient concentration (Nut), CO2 partial pressure (CO2), and light regime (Mix)—to determine how the Pc of nine freshwater phytoplankton communities, found along a Kd gradient in Mediterranean ecosystems, changed as the number of interacting drivers increased. Our findings indicated that UVR was the dominant driver, its effect being between 3–60 times stronger, on average, than that of any other driver tested. Also, UVR had the largest difference in driver magnitude of all the treatments tested. A future UVR × CO2 × Mix × Nut scenario exerted a more inhibitory effect on Pc as the water column became darker. However, the magnitude of this synergistic effect was 40–60% lower than that exerted by double and triple interactions and by UVR acting independently. These results illustrate that although future global-change conditions could reduce Pc in Mediterranean lakes, multiple interacting drivers can temper the impact of a severely detrimental driver (i.e. UVR), particularly as the water column darkensMinisterio de Ciencia, Innovación y Universidades | Ref. FJCI2017-32318Ministerio de Economía y Competitividad | Ref. CGL2015-67682-RMinisterio de Economía y Competitividad | Ref. CGL2011-23681Ministerio de Medio Ambiente y Medio Rural y Marino | Ref. PN2009/067Junta de Andalucía | Ref. P09-RNM-5376Junta de Andalucía | Ref. Excelencia CVI-0259

Charged pseudoscalar and vector meson masses under strong magnetic fields in an extended NJL model

The mass spectrum of $\pi^+$ and $\rho^+$ mesons in the presence of a static uniform magnetic field $\vec B$ is studied within a two-flavor NJL-like model. We improve previous calculations taking into account the effect of Schwinger phases carried by quark propagators, and using an expansion of meson fields in terms of the solutions of the corresponding equations of motion for nonzero $B$. It is shown that the meson polarization functions are diagonal in this basis. Our numerical results for the $\rho^+$ meson spectrum are found to disfavor the existence of a meson condensate induced by the magnetic field. In the case of the $\pi^+$ meson, $\pi$ - $\rho$ mixing effects are analyzed for the meson lowest energy state. The predictions of the model are compared with available lattice QCD results.Comment: 35 pages, 4 figures. arXiv admin note: text overlap with arXiv:2205.1592

Direct and indirect effects of vertical mixing, nutrients and ultraviolet radiation on the bacterioplankton metabolism in high-mountain lakes from southern Europe

As a consequence of global change, modifications in the interaction among abiotic stressors on aquatic ecosystems have been predicted. Among other factors, UVR transparency, nutrient inputs and shallower epilimnetic layers could alter the trophic links in the microbial food web. Currently, there are some evidences of higher sensitiveness of aquatic microbial organisms to UVR in opaque lakes. Our aim was to assess the interactive direct and indirect effects of UVR (through the excretion of organic carbon – EOC – by algae), mixing regime and nutrient input on bacterial metabolism. We performed in situ short-term experiments under the following treatments: full sunlight (UVR + PAR, >280 nm) vs. UVR exclusion (PAR only, >400 nm); ambient vs. nutrient addition (phosphorus (P; 30 μg PL−1) and nitrogen (N; up to final N : P molar ratio of 31)); and static vs. mixed regime. The experiments were conducted in three high-mountain lakes of Spain: Enol [LE], Las Yeguas [LY] and La Caldera [LC] which had contrasting UVR transparency characteristics (opaque (LE) vs. clear lakes (LY and LC)). Under ambient nutrient conditions and static regimes, UVR exerted a stimulatory effect on heterotrophic bacterial production (HBP) in the opaque lake but not in the clear ones. Under UVR, vertical mixing and nutrient addition HBP values were lower than under the static and ambient nutrient conditions, and the stimulatory effect that UVR exerted on HBP in the opaque lake disappeared. By contrast, vertical mixing and nutrient addition increased HBP values in the clear lakes, highlighting for a photoinhibitory effect of UVR on HBP. Mixed regime and nutrient addition resulted in negative effects of UVR on HBP more in the opaque than in the clear lakes. Moreover, in the opaque lake, bacterial respiration (BR) increased and EOC did not support the bacterial carbon demand (BCD). In contrast, bacterial metabolic costs did not increase in the clear lakes and the increased nutrient availability even led to higher HBP. Consequently, EOC satisfied BCD in the clear lakes, particularly in the clearest one [LC]. Our results suggest that the higher vulnerability of bacteria to the damaging effects of UVR may be particularly accentuated in the opaque lakes and further recognizes the relevance of light exposure history and biotic interactions on bacterioplankton metabolism when coping with fluctuating radiation and nutrient inputs.Fil: Durán, C.. Universidad de Granada; EspañaFil: Medina Sánchez, J. M.. Universidad de Granada; EspañaFil: Herrera, G.. Universidad de Granada; EspañaFil: Villar Argaiz , M.. Universidad de Granada; EspañaFil: Villafañe, Virginia Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Helbling, Eduardo Walter. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Carrillo, P.. Universidad de Granada; Españ