856 research outputs found

    Tumor Necrosis Factor and the Pathophysiology of Septic Shock

    Get PDF

    Utilización de los huesos de la cabeza, cintura pectoral y otolitos para estimar la talla y el peso de la anchoíta (Engraulis anchoita), especie clave en el ecosistema marino patagónico

    Get PDF
    The Argentine anchovy, Engraulis anchoita, plays a vital role as a key prey species for several marine predators in the north Patagonian marine ecosystem of the Atlantic Ocean. Reconstructing the length and weight of each consumed specimen is essential to provide a detailed description of the trophic ecology of top marine predators. Predictive linear regression equations were calculated for the Patagonian stock of Argentine anchovy to estimate parameters of length-weight relationships using measurements of whole individuals and diagnostic elements such as otoliths, head bones and pectoral fin bones. Among the diagnostic elements analyzed, the cleithrum and dentary exhibited the best fit. This study validates the use of head and pectoral girdle bones as reliable indicators for predicting the weight and length of Argentine anchovy across a wide size range, which corresponds to the target range of various predators. These relationships can contribute to the determination of body condition, estimation of consumed biomass, and calculation of energy density, providing valuable insights into the trophic ecology of predators in the southern Atlantic Ocean.La anchoíta, Engraulis anchoita, juega un papel vital como especie presa clave para varios depredadores marinos en el ecosistema marino patagónico norte del Océano Atlántico. Reconstruir la longitud y el peso de cada espécimen consumido es esencial para proporcionar una descripción detallada de la ecología trófica de los principales depredadores marinos. Se calcularon las ecuaciones de regresión lineal predictiva para el stock patagónico de anchoíta, a fin de estimar los parámetros de las relaciones talla-peso utilizando medidas de individuos completos y elementos de diagnóstico como otolitos, huesos de la cabeza y huesos de la aleta pectoral. Entre los elementos diagnósticos analizados, el cleitro y el dentario exhibieron el mejor ajuste. Este estudio valida el uso de los huesos de la cabeza y la cintura pectoral como indicadores confiables para predecir el peso y la talla de la anchoíta en un amplio rango de tamaños, que corresponden al rango objetivo de varios depredadores. Estas relaciones pueden contribuir a la determinación de la condición corporal, la estimación de la biomasa consumida y el cálculo de la densidad de energía, proporcionando información valiosa sobre la ecología trófica de los depredadores en el Océano Atlántico sur

    Evolutionary implications of dental eruption in Dasypus (Xenarthra)

    Get PDF
    Late eruption of the permanent dentition was recently proposed as a shared anatomical feature of endemic African mammals (Afrotheria), with anecdotal reports indicating that it is also present in dasypodids (armadillos). In order to clarify this question, and address the possiblity that late eruption is shared by afrotherians and dasypodids, we quantified the eruption of permanent teeth in Dasypus, focusing on growth series of D. hybridus and D. novemcinctus. This genus is the only known xenarthran that retains two functional generations of teeth. Its adult dentition typically consists of eight upper and eight lower ever-growing (or euhypsodont) molariforms, with no premaxillary teeth. All but the posterior-most tooth are replaced, consistent with the identification of a single molar locus in each series. Comparison of dental replacement and skull metrics reveals that most specimens reach adult size with none or few erupted permanent teeth. This pattern of growth occurring prior to the full eruption of the dentition is similar to that observed in most afrotherians. The condition observed in Dasypus and many afrotherians differs from that of most other mammals, in which the permanent dentition erupts during (not after) growth, and is complete at or near the attainment of sexual maturity and adult body size. The suture closure sequence of basicranial and postcranial epiphyses does not correlate well with dental eruption. The basal phylogenetic position of the taxon within dasypodids suggests that diphyodonty and late dental replacement represent the condition of early xenarthrans. Additionally, the inferred reduction in the number of molars to a single locus and the multiplication of premolars represent rare features for any living mammal, but may represent apomorphic characters for Dasypus.Fil: Ciancio, Martin Ricardo. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Cordeiro de Castro, Mariela. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Galliari, Fernando Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; ArgentinaFil: Carlini, Alfredo Armando. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; ArgentinaFil: Asher, Robert J.. University of Cambridge; Estados Unido

    Acoustic telemetry and accelerometers: a field comparison of different proxies for activity in the marine environment

    Get PDF
    Different proxies for activity are used in the field of acoustic telemetry, a leading technology for the study of behaviour in the aquatic environment. Acoustic telemetry poses some shortcomings that may condition data interpretation. Here, we assessed some approaches commonly used to infer activity from acoustic telemetry data using acceleration biologgers as a benchmark. Specifically, we assessed (1) the performance of internal acceleration transmitters, (2) the consequences of averaging acceleration data into increasing time bins, (3) the occurrence of sampling bias in telemetry data acquisition, and (4) the performance of the number of detections and the depth range as proxies for activity. Despite some constraints of acoustic telemetry, acceleration transmitters had a good performance. Conversely, the number of detections and the depth range did not match well the activity estimates provided by acceleration biologgers. Besides, our results pointed to some issues in models concerning the predictive power of acceleration transmitters (linear predictor) over acceleration biologgers, warned about potential sampling bias associated with data acquisition with acoustic telemetry, and highlighted the relevance of considering inter-individual differences in behavioural studies. Finally, we provided some methodological perspectives that should be considered to plan fieldwork, analyse data, and interpret results on animal activity obtained with acoustic telemetry.info:eu-repo/semantics/publishedVersio

    Pediatric kidney transplants with multiple renal arteries show no increased risk of complications compared to single renal artery grafts

    Get PDF
    BackgroundKidney allografts with multiple renal arteries (MRA) are not infrequent and have been historically associated with a higher risk of developing vascular and urologic complications. Reports of kidney transplantation using MRA allografts in the pediatric population remain scarce. The aim of this study was to evaluate if transplantation of allografts with MRA with a surgical intent of creating a single arterial inflow using vascular reconstruction techniques when required, and without the routine use of surgical drains or ureteral stents, is associated with an increased risk of complications when compared to single renal artery (SRA) grafts.MethodsWe retrospectively analyzed all pediatric renal transplant recipients performed by a single surgeon at our center between January 2015 and June 2022. Donor and recipient demographics, intraoperative data, and recipient outcomes were included. Recipients were divided into two groups based on SRA vs. MRA. Baseline variables were described using frequency distributions for categorical variables and means and standard errors for continuous variables. Comparisons of those distributions between the two groups were performed using standard chi-squared and t-tests. Time-to-event distributions were compared using the log-rank test.ResultsForty-nine pediatric transplant recipients were analyzed. Of these, 9 had donors with MRA (Group 1) and 40 had donors with SRA (Group 2). Native kidney and liver mobilization was performed in 44.4% (4/9) of Group 1 vs. 60.0% (24/40) of Group 2 cases (p = 0.39). There were no cases of delayed graft function or graft primary nonfunction. No surgical drainage or ureteral stents were used in any of the cases. One patient in Group 2 developed a distal ureter stricture. The geometric mean serum creatinine at 6- and 12-months posttransplant was 0.7 */ 1.2 and 0.9 */ 1.2 mg/dl in Group 1 and 0.7 */ 1.1 and 0.7 */ 1.1 mg/dl in Group 2. Two death-censored graft failures were observed in Group 2, with no significant difference observed between the two groups (p = 0.48).ConclusionsOur study demonstrates that pediatric renal transplantation with MRA grafts, using a surgical approach to achieve a single renal artery ostium, can be safely performed while achieving similar outcomes as SRA grafts and with a low complication rate

    Analysis of Metal-Insulator Crossover in Strained {SrRuO}3 Thin Films by X-ray Photoelectron Spectroscopy

    Get PDF
    The electronic properties of ultrathin epitaxial films of strontium ruthenate SrRuO3 perovskite oxide are modified by epitaxial strain, as determined by growing by pulsed laser deposition, on different the substrates. Electron transport measurements indicated that tensile strain deformation of the SrRuO3 unit cell reduces the metallicity of the material and reduces the metal-insulator-transition (MIT) temperatures. The shrinkage of the Ru-O-Ru buckling angle due to compressive strain is counterweighted by the increased overlap of the conduction Ru-4d orbitals with the O-2p ones due to the smaller interatomic distances resulting into an increased MIT temperature, i.e. a more conducting material. In the more metallic samples the core level x-ray photoemission spectroscopy lineshapes show the occurrence of an extra-peak at the lower binding energies of the main Ru-3d peaks that is attributed to screening, as observed in volume sensitive photoemission of the unstrained material

    Retrospective Assessment of Islet Cell Autoantibodies in Pancreas Organ Donors

    Get PDF
    OBJECTIVE—Of deceased pancreas donors, 3–4% may have autoantibodies (AAb) to pancreatic islet cell antigens; these autoantibodies are well-established markers of type 1 diabetes. We investigated whether donor AAb positivity could affect the outcome of pancreas transplantation
    corecore