21 research outputs found
Serological and Molecular Evaluation of Ehrlichiosis, Babesiosis and Leishmaniosis in Concórdia Municipality, Santa Catarina, Brazil
To evaluate occurrences of ehrlichiosis, babesiosis and canine leishmaniasis in the municipality of Concórdia, Santa Catarina, Brazil. Blood was collected from 424 dogs that were attended at the Clinical Practice Center of the Federal Institute of Santa Catarina, Concordia campus, and also in private clinics in the city or in its rural zone. Animals were evaluated first by serological tests, and among them, 191 dogs were proportionally and randomly chosen to undergo the molecular test. The presence of antibodies against Leishmania infantum was investigated using the Indirect Immunofluorescent Antibody Test and against Babesia canis and Ehrlichia canis using the Enzyme-linked Immunosorbent Assay, along with the Polymerase Chain Reaction for the three agents. The chi-square test at the significance level of 5% was used to compare the positive and negative animals in the population sampled. Among the samples evaluated in the serological tests, 43.45%, 43.98% and 14.66% were positive for ehrlichiosis, babesiosis and leishmaniasis, respectively. In the molecular test, only 4.19% of the samples were positive for babesiosis. Anti-E. canis, anti-B. canis and anti-L. infantum antibodies were present in the canine population studied. Due to the serological tests used for the use of IgG immunoglobulin, it is suggested that seropositive animals come into contact with the parasite previously and possibly have developed immunity against them. The polymerase chain reaction indicated that the positive animals had the genetic material of the parasite at that time, indicating that they were possibly at an early stage of the disease
Serological survey of Ehrlichia canis, Babesia canis and Leishmania infantum in a Brazilian canine population
Este estudo avaliou as ocorrências de babesiose, erliquiose e leishmaniose e a presença de coinfecção por essas doenças em cães do município de Concórdia, no oeste do estado de Santa Catarina (SC), Brasil. O sangue foi coletado de 424 cães atendidos no Centro de Prática Clínica do Instituto Federal de Santa Catarina, Concórdia, e também em clínicas da cidade e de sua zona rural. A presença de anticorpos contra Leishmania infantum foi investigada pela reação de Imunofluorescência Indireta (IIF) e contra Babesia canis e Ehrlichia canisusando o ensaio imunoabsorvente ligado a enzima (ELISA). O teste do qui-quadrado, ao nível de significância de 5%, foi utilizado para comparar os animais positivos e negativos na população amostrada. Das 424 amostras avaliadas, 170 (40,09%) foram positivas para erliquiose, 178 (41,98%) foram positivas para babesiose e 59 (13,91%) foram positivas para leishmaniose. Houve diferenças estatísticas quanto à erliquiose em relação às variáveis de área, acesso à rua e raça. Além disso, entre as amostras positivas, houve reações de co-infecção. A partir desses resultados, pode-se sugerir que essas três doenças estão presentes no município de Concórdia, SC
Optimization of parameters in electron probe microanalysis
A method for the refinement of atomic and experimental parameters applicable to several spectroscopic techniques is presented. This kind of procedure, previously used in x-ray diffraction, is shown to be a powerful tool in electron probe microanalysis (EPMA). This method consists of minimizing the differences between an experimental x-ray spectrum and a function proposed to account for the bremsstrahlung and characteristic peaks from the corresponding sample, and also for detection artifacts. This complicated function involves several parameters related to different sources (x-ray production, x-ray attenuation, sample composition, x-ray detection, etc.). Initial values must be supplied for them, and after a numerical iterative procedure is performed, improved values are achieved. Depending on the particular situation, certain parameters may be known a priori, so that they can be fixed, allowing the others to vary. In this way, the method can be used for different purposes: determination of atomic parameters such as fluorescence yields transition rates or photoelectric cross-sections, quantitative standardless analysis, determination of detector characteristics, etc. This work is intended to present the general aspects of the method for refining EPMA parameters, and to give some examples of its application to the aforementioned issues. Even when only EPMA spectra are included in this work, the method can be applied to different spectroscopic techniques, such as x-ray fluorescence, particle-induced x-ray emission, etc. Copyright © 2001 John Wiley & Sons, Ltd.Fil: Bonetto, Rita Dominga. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; ArgentinaFil: Castellano, Gustavo Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Trincavelli, Jorge Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentin
Determination of L-shell intensity ratios for Yb, Hf and Ta by a parameter refinement method
Transition rates for radiative decays to the L-shell were obtained for Yb, Hf and Ta by means of a method of experimental and atomic parameter refinement in x-ray fluorescence. An analytical function accounts for continuum and characteristic radiation detection artifacts are also included in the spectral description. The procedure of parameter refinement consists of minimizing quadratic differences between the experimental and predicted spectra through the optimization of the parameters involved in the analytical expression used. Spectra were acquired in an energy-dispersive system with synchrotron monochromatic beams. The results obtained for the sought transition rates are in agreement with the scarce values found in the literature. Copyright ©2004 John Wiley & Sons, Ltd.Fil: Carreras, Alejo Cristian. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; ArgentinaFil: Trincavelli, Jorge Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; ArgentinaFil: Bonetto, Rita Dominga. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; ArgentinaFil: Castellano, Gustavo Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentin
L-shell radiative transition rates by selective synchrotron ionization
Relative L-shell radiative transition rates were obtained for a number of decays in Gd, Dy, Er, Yb, Hf, Ta and Re by means of a method for refining atomic and experimental parameters involved in the spectral analysis of x-ray irradiated samples. For this purpose, pure samples were bombarded with monochromatic synchrotron radiation tuning the incident x-ray energy in order to allow selective ionization of the different atomic shells. The results presented are compared to experimental and theoretical values published by other authors. A good general agreement was found and some particular discrepancies are discussed.Fil: Bonetto, Rita Dominga. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; ArgentinaFil: Carreras, Alejo Cristian. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; ArgentinaFil: Trincavelli, Jorge Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; ArgentinaFil: Castellano, Gustavo Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentin
Optimization of K-shell intensity ratios in electron probe microanalysis
A method for refinement of atomic and experimental parameters was applied to the optimization of K-shell intensity ratios in electron probe microanalysis (EPMA). This kind of procedure, previously used in x-ray diffraction, is shown to be a powerful tool in EPMA. The method consists of minimizing the differences between an experimental x-ray spectrum and a function proposed to account for the bremsstrahlung and characteristic peaks from the corresponding sample, and also for detection artifacts. In this work, the method was used for the determination of transition rates. This procedure was applied to 14 elements with atomic numbers ranging from 20 to 42. The results obtained are in agreement with theoretical and experimental data for Kα/(Kβ + Kα) intensity ratios. In addition, Kα1, Kα2, Kβ1, and Kβ2 relative intensities were compared with experimental data, showing a similar behaviour. Copyright © 2002 John Wiley & Sons, Ltd.Fil: Castellano, Gustavo Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; ArgentinaFil: Bonetto, Rita Dominga. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; ArgentinaFil: Trincavelli, Jorge Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; ArgentinaFil: Vasconcellos, M.. Universidade Federal do Rio Grande do Sul; BrasilFil: Campos, C.. Universidade Federal do Rio Grande do Sul; Brasi
Reduced rDNA transcription diminishes skeletal muscle ribosomal capacity and protein synthesis in cancer cachexia
Muscle wasting in cancer is associated with deficits in protein synthesis, yet, the mechanisms underlying this anabolic impairment remain poorly understood. The capacity for protein synthesis is mainly determined by the abundance of muscle ribosomes, which is in turn regulated by transcription of the ribosomal (r)RNA genes (rDNA). In this study, we investigated whether muscle loss in a preclinical model of ovarian cancer is associated with a reduction in ribosomal capacity and was a consequence of impaired rDNA transcription. Tumor bearing resulted in a significant loss in gastrocnemius muscle weight and protein synthesis capacity, and was consistent with a significant reduction in rDNA transcription and ribosomal capacity. Despite the induction of the ribophagy receptor NUFIP1 mRNA and the loss of NUFIP1 protein, in vitro studies revealed that while inhibition of autophagy rescued NUFIP1, it did not prevent the loss of rRNA. Electrophoretic analysis of rRNA fragmentation from both in vivo and in vitro models showed no evidence of endonucleolytic cleavage, suggesting that rRNA degradation may not play a major role in modulating muscle ribosome abundance. Our results indicate that in this model of ovarian cancer-induced cachexia, the ability of skeletal muscle to synthesize protein is compromised by a reduction in rDNA transcription and consequently a lower ribosomal capacity. Thus, impaired ribosomal production appears to play a key role in the anabolic deficits associated with muscle wasting in cancer cachexia
Parameter refinement in the analysis of X-ray irradiated samples
Although the refinement of parameters is a well known method in the scope of X-ray diffraction, it also appears as a powerful tool in other spectroscopic techniques. This work presents a method for the refinement of different atomic and experimental parameters in X-ray fluorescence (XRF). It consists of minimizing the differences between an experimental X-ray spectrum and a function proposed to account for the characteristic peaks and background spectrum from the corresponding sample, as well as for detection artifacts. The algorithm starts from some initial values for the different parameters involved, and a numerical iterative procedure produces improved values for them. After the general aspects of the method for refining XRF parameters are presented, a simple application is given for spectra measured in metallic samples with a monochromatic beam from a synchrotron source. In this case, the optimization algorithm is used for the determination of relative transition probabilities for the K shell. Copyright © 2002 John Wiley & Sons, Ltd.Fil: Carreras, Alejo Cristian. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; ArgentinaFil: Bonetto, Rita Dominga. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; ArgentinaFil: Stutz, Guillermo Eduardo. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; ArgentinaFil: Trincavelli, Jorge Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; ArgentinaFil: Castellano, Gustavo Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentin
Effect of Aquatic Vegetation on the Persistence of Cypermethrin Toxicity in Water
Soybean production in Argentina comprises 15 million ha. Cypermethrin is the main insecticide applied amounting 150 g of active ingredient per hectare, thus representing roughly 2.3 thousand tons yearly released to the environment. Toxicity pulses have been observed in small streams draining agricultural basins, most of them sustaining macrophyte growth. Cypermethrin concentrations and its toxicity to the amphipod Hyalella curvispina was compared following an addition to laboratory mesocosms with and without a vegetation cover of the floating macrophyte Lemna sp. Both concentrations and toxicity decreased faster in the treatments covered with Lemna. Fast adsorption of the hydrophobic pesticide to the roots and fronds of Lemna was suggested.Instituto de Limnología "Dr. Raúl A. Ringuelet"Centro de Investigaciones del Medioambient
Metastatic or xenograft colorectal cancer models induce divergent anabolic deficits and expression of pro-inflammatory effectors of muscle wasting in a tumor-type-dependent manner
We investigated the impact of tumor burden on muscle wasting in metastatic (m) and xenograft (x) models of colorectal cancer (CRC). Male Nod SCID γ and CD2F1 mice were injected subcutaneously or intrasplenically with HCT116 or C26 tumor cells, respectively. CRC tumors resulted in significant muscle wasting regardless of tumor type or model, although muscle loss was exacerbated in mHCT116 hosts. The mHCT116 model decreased ribosomal (r)RNA content and rDNA transcription, whereas the mC26 model showed no loss of rRNA and the upregulation of rDNA transcription. The xHCT116 model reduced mTOR, RPS6, and 4E-BP1 phosphorylation, whereas the mHCT116 model had a similar effect on RPS6 and 4E-BP1 without altering mTOR phosphorylation. The C26 models caused a reduction in 4E-BP1 phosphorylation independent of mTOR. Muscle interleukin (IL)-6 mRNA was elevated in all models except xHCT116, and the NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) mRNA was induced only in the mC26 model. IL-1β mRNA increased in all groups with greater expression in metastatic relative to the xenograft model regardless of tumor types. Our findings indicate that HCT116 tumor burden results in more drastic muscle wasting and anabolic deficits, whereas C26 tumor burden causes similar muscle wasting but exhibits a divergent proinflammatory phenotype. These results highlight potentially important divergence in the pathogenesis of muscle wasting among preclinical models of CRC and demonstrate that tumor burden plays a role in determining anabolic deficits and the expression of proinflammatory effectors of muscle wasting in a tumor-type-dependent manner.
NEW & NOTEWORTHY We provide evidence demonstrating that colorectal tumor burden plays a role in determining anabolic deficits and the expression of proinflammatory effectors of muscle wasting in a tumor-type-dependent manner