Browsing by Author "Sabat, P."
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- ItemAdjustments of the oxygen diffusing capacity to energetic demands during the development of the quail (Coturnix coturnix japonica)(2011) Canals, M.; Martinez, B. B.; Figueroa, D.; Sabat, P.One of the hypotheses that attempt to explain physiological limitations of energy budgets is the symmorphosis hypothesis, which proposes that if matching structures to functional needs were combined with the strict economy of energy and materials, the result would be an optimal organ design for the specific function it serves. Evidence in favor of symmorphosis in adults is as abundant as evidence against it, but the plasticity of some morphological traits may be dependent on the ontogenetic stage at which acclimation acts. Thus, here we studied the adjustment of structure and function in lungs at different stages of development in the quail Coturnix coturnix japonica under two thermal regimes. Our main results show that i) resting metabolic rate, maximum thermogenic oxygen consumption and oxygen diffusion capacity did not exhibit developmental plasticity for two thermal environments: and ii) oxygen diffusion capacity fully adjusted to resting metabolic rate and maximum oxygen consumption during development. C coturnix has a low safety factor close to 1 which is consistent with the symmorphosis hypothesis. (C) 2011 Elsevier Inc. All rights reserved.
- ItemClinical Features and Prognostic Factors in Presumed Ocular Tuberculosis(2017) Castiglione E.; Calonge, M.; Urzua, C.; Lantigua, Y.; Abuauad, S.; Liberman Salazar, Paulina; Berger, O.; Sabat, P.; Velásquez, V.
- ItemComparative basal metabolic rate among passerines and the food habit hypothesis(2010) Sabat, P.; Bozinovic Kuscevic, Francisco
- ItemCoping with salt water habitats : metabolic and oxidative responses to salt intake in the rufous-collared sparrow(2017) Nespolo Rossi, Roberto; Bozinovic Kuscevic, Francisco; Sabat, P.; Narváez, C.; Peña Villalobos, I.; Contreras, C.; Maldonado, K.; Sánchez Hernández, J.; Newsome, S.
- ItemDigestive Plasticity and the Cost of Acclimation to Dietary Chemistry in the Omnivorous Leaf-Eared Mouse Phyllotis Darwini(2000) Sabat, P.; Bozinovic Kuscevic, Francisco
- ItemDo changes in dietary chemistry during ontogeny affect digestive performance in adults of the herbivorous rodent Octodon degus?(2008) Sabat, P.; Bozinovic Kuscevic, Francisco
- ItemEarly life experience drives short-term acclimation of metabolic and osmoregulatory traits in the leaf-eared mouse(2017) Cavieres Parada, Grisel Beatriz; Núñez, M.; Bozinovic Kuscevic, Francisco; Sabat, P.
- ItemEffect of gestational and postnatal environmental temperature on metabolic rate in the altricial rodent, Phyllotis darwini(2009) Canals, M.; Figueroa, D. P.; Miranda, J. P.; Sabat, P.1. In the altricial rodent, Phyllotis darwini, we found higher body temperatures and faster developmental rates of the thermoregulatory, capacity in neonates born from cold- than warm-acclimated mothers.
- ItemGeographic variation in the response to thermal acclimation in rufous-collared sparrows: are physiological flexibility and environmental heterogeneity correlated?(2008) Cavieres, G.; Sabat, P.1. It has been proposed that habitats with low productivity, and hence low resource availability, may favour individuals with lower rates of resource use and energy expenditure. In birds, some studies have shown that basal metabolic rate (BMR) and total evaporative water loss (TEWL) are reduced in desert bird species compared to those that live in more mesic areas. However, the contribution of the phenotypic plasticity of birds to this pattern has been poorly studied.
- ItemIntegrated biomarker analysis of chlorpyrifos metabolism and toxicity in the earthworm Aporrectodea caliginosa(2014) Sanchez-Hernandez, Juan C.; Narvaez, C.; Sabat, P.; Martinez Mocillo, S.To increase our understanding about the mode of toxic action of organophosphorus pesticides in earthworms, a microcosm experiment was performed with Aporrectodea caliginosa exposed to chlorpyrifos-spiked soils (0.51 and 10 mg kg-(1) dry soil) for 3 and 21 d. Acetylcholinesterase (AChE), carboxylesterase (CbE), cytochrome P450-dependent monooxygenase (CYP450), and glutathione S-transferase (GST) activities were measured in the body wall of earthworms. With short-termexposure, chlorpyrifos inhibited CbE activity (51-89%) compared with controls in both treated groups, whereas AChE activity was depressed in the 10-mg kg(-1) group (87% inhibition). With long-term exposure, chlorpyrifos strongly inhibited all esterase activities (84-97%). Native electrophoresis revealed three AChE isozymes, two of which showed a decreased staining corresponding to the level of pesticide exposure. The impact of chlorpyrifos on CbE activity was also corroborated by zymography. CYP450 activity was low in unexposed earthworms, but it increased (1.5- to 2.4-fold compared to controls) in the earthworms exposed to both chlorpyrifos concentrations for 3 d. Bioactivation of chlorpyrifos was determined by incubating the muscle homogenate in the presence of chlorpyrifos and NAD(H)(2). The mean (+/- SD, n = 40) bioactivation rate in the unexposed earthworms was 0.74 +/- 0.27 nmol NAD(H)(2) oxidized min(-1) mg(-1) protein, and a significant induction was detected in the low/short-term exposure group. GST activity significantly increased (33-35% of controls) in earthworms short-term exposed to both chlorpyrifos concentrations. Current data showed that CYP450 and GST activities had a prominent role in the initial exposure to the organophosphorus. With short-term exposure, CbE activity was also a key enzyme in the non-catalytic detoxification of chlorpyrifos-oxon, thereby reducing its impact on AChE activity, before it became saturated at t=21 d. Results indicate that A. caliginosa detoxify efficiently chlorpyrifos, which would explain its tolerance to relatively high exposure levels to chlorpyrifos. (C) 2014 Elsevier B.V. All rights reserved.
- ItemIs Maximum Food Intake in Endotherms Constrained by Net or Factorial Aerobic Scope? Lessons from the Leaf-Eared Mouse(2016) Maldonado, K.; Sabat, P.; Piriz, G.; Bogdanovich, J.; Nespolo Rossi, Roberto; Bozinovic Kuscevic, Francisco
- ItemNutritional ecology and ecological immunology in degus : Does early nutrition affect the postnatal development of the immune function?(2020) Ramírez Otarola, N.; Maldonado, K.; Cavieres Parada, Grisel Beatriz; Bozinovic Kuscevic, Francisco; Sabat, P.
- ItemOsmoregulation and adaptive radiation in the ovenbird genus Cinclodes (Passeriformes: Furnariidae)(2006) Sabat, P.; Maldonado, K.; Canals, M.; Martinez Del Rio, C.1. The genus Cinclodes is unique among passerines because it includes two species that can be considered marine/coastal and also includes several species that inhabit freshwater streams or that shift habitats between terrestrial/fresh water and marine habitats. The Cinclodes clade satisfies two criteria of an adaptive radiation: it is monophyletic and it experienced recent speciation accompanied by rapid phenotypic diversification.
- ItemPrimer Consenso Chileno de Grupo de Estudio de Tuberculosis Ocular(Sociedad Chilena de Infectologia, 2023) Urzua, C.A.; Liberman Salazar, Paulina; Escobar, N.; Sabat, P.; Hernández, M.; Peña García, Luis Enrique; Stevenson, R.; Pérez, M.E.; Balcells Marty, María ElviraThe treatment of ocular tuberculosis (TB) remains controver-sial worldwide. The development of guidelines for ocular TB can facilitate the approach and management of these patients. These guidelines should be developed regionally, considering the local TB epidemiology. The objectives of this consensus are: to initiate an in-terdisciplinary discussion about the epidemiology, pathophysiology, clinical presentation, diagnosis, workup and treatment of patients with ocular TB, to establish a treatment algorithm and define which patients should be treated in Chile and how and, to analyze and discuss the published data regarding chemoprophylaxis for patients with latent TB who need to start immunosuppressive treatment due to inflammatory ocular conditions.
- ItemPulmonary hematological parameters, energetic flight demands and their correlation with oxygen diffusion capacity in the lungs(2007) Canals, M.; Donoso, C.; Figueroa, D.; Sabat, P.Hematological parameters of birds and mammals seem to respond to environmental requirements, such as hypoxia at high altitude and the energetic demands of locomotion and flight. In this work we hypothesize that lung capillary hematocrit and red blood size may be influenced by the energetic requirements of flight. Also, we propose that hematological parameters should vary together with the morphological parameters that determine oxygen diffusion capacity. We analyzed the red blood cell size and the local characteristics of the pulmonary capillary hematocrit correlating these with the pulmonary factors that determines the oxygen diffusion capacity. We deal with seven species, non-flying and flying birds and mammals, with different energetic requirements. The capillary hematocrit was not different in each taxon, but the red blood cell size was smaller in flying mammals and birds than non-flying ones. Correlation of erythrocyte size with the diffusing characteristics of the lungs produced a non-phylogenetic clustering with a group constituting by the bats Tadarida brasiliensis y Myotis chiloensis, and the bird Z. auriculata; revealing similar functional response in unrelated species. Finally, in mammals, a negative correlation between the red blood cell size and the mass-specific oxygen diffusion capacity was obtained. These results suggest that the direction of the hematological and pulmonary adjustments is governed mainly by the requirements of flight independent of phylogenetic origin of the species studied.
- ItemThe interplay between ambient temperature and salt intake affects oxidative status and immune responses in a ubiquitous Neotropical passerine, the rufous-collared sparrow(2019) Sabat, P.; Bozinovic Kuscevic, Francisco; Contreras Ramos, C.; Nespolo Rossi, Roberto; Newsome, S. D.; Quirici, V.; Maldonado, K.; Peña Villalobos, I.; Ramírez-Otárola, N.; Sánchez Hernández, J. C.
- ItemThe isotopic composition and insect content of diet predict tissue isotopic values in a South American passerine assemblage(2013) Sabat, P.; Bozinovic Kuscevic, Francisco