1
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Vidal MA, Rezende EL, Bacigalupe LD. Intra and interspecific variation in thermal performance and critical limits in anurans from southern Chile. J Therm Biol 2024; 121:103851. [PMID: 38615494 DOI: 10.1016/j.jtherbio.2024.103851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 03/19/2024] [Accepted: 03/19/2024] [Indexed: 04/16/2024]
Abstract
The relationship between temperature and performance can be illustrated through a thermal performance curve (TPC), which has proven useful in describing various aspects of ectotherms' thermal ecology and evolution. The parameters of the TPC can vary geographically due to large-scale variations in environmental conditions. However, only some studies have attempted to quantify how thermal performance varies over relatively small spatial scales, even in the same location or consistently among individuals within a species. Here, we quantified individual and species variation in thermal sensitivity of locomotor performance in five amphibia Eupsophus species found in the temperate rainforests of southern Chile and compared their estimates against co-occurring species that exhibit a substantially more extensive distributional range. We measured critical thermal limits and jumping performance under five different temperatures. Our results suggest that thermal responses are relatively conserved along the phylogeny, as the locomotor performance and thermal windows for activity remained narrow in Eupsophus species when compared against results observed for Batrachyla taeniata and Rhinella spinulosa. Additionally, we found significant individual differences in locomotor performance within most species, with individual consistency in performance observed across varied temperatures. Further analyses explored the influence of body size on locomotor performance and critical thermal limits within and between species. Our results suggest a trade-off scenario between thermal tolerance breadth and locomotor performance, where species exhibiting broader thermal ranges might have compromised performance. Interestingly, these traits seem partly mediated by body size variations, raising questions about potential ecological implications.
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Affiliation(s)
- Marcela A Vidal
- Center of Ñuble Studies, Biodiversity and Global Change Research Group, Departament of Basic Sciences, Faculty of Sciences, Bío-Bío University, Av. Andrés Bello 720, Chillán, Chile.
| | - Enrico L Rezende
- Department of Ecology, Center od Applied Ecology and Sustainability (CAPES), Faculty of Biological Sciences, Pontifical Catholic University of Chile, Santiago, 6513677, Chile
| | - Leonardo D Bacigalupe
- Institute of Environmental and Evolutionary Sciences, Austral University of Chile, Valdivia, Chile
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2
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Vidal MA, Henríquez N, Torres-Díaz C, Collado G, Acuña-Rodríguez IS. Identifying Strategies for Effective Biodiversity Preservation and Species Status of Chilean Amphibians. Biology (Basel) 2024; 13:169. [PMID: 38534439 DOI: 10.3390/biology13030169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Revised: 02/28/2024] [Accepted: 02/29/2024] [Indexed: 03/28/2024]
Abstract
Resources are limited in global biodiversity conservation efforts, which emphasizes the significance of setting conservation priorities. Using standardized criteria, we evaluated 58 amphibian species in Chile to determine their conservation priority (CP). Species with insufficient historical data had their values marked as missing. With a median value of p = 1.67, the results demonstrated CP values ranging from p = 0.48 to p = 3.0, classifying species into priority and non-priority groups. Four levels were established for the priority categories: no priority, low priority, medium priority, and high priority. Additionally, the Telmatobiidae and Alsodidae families were identified as two more priority families. Notably, the species with the highest priority were found to be T. halli, T. fronteriensis, T. philippii, T. chusmisensis, A. pehuenche, and Alsodes tumultuosus, where T. philippii and T. fronteriensis have equal priority for conservation at the national level according to the conservation priority analysis. Eight priority families-the Alsodidae, Batrachylidae, Bufonidae, Ceratophryidae, Leptodactylidae, Rhinodermatidae, and Telmatobiidae-were determined, and 14 species-or 24% of the species examined-need further study. Based on the conservation priority analysis, the species T. fronteriensis and T. philippii share the highest priority for conservation at the national level (p = 2.50). With 70% of the amphibians under study being threatened mainly by habitat loss, pollution, and emerging diseases, the creation of conservation categories made the threat assessment process easier. Due to a lack of information on geographic distribution and abundance, quantitatively classifying amphibians in Chile remains difficult. The analysis of conservation priorities and potential extinction threats informs appropriate management strategies.
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Affiliation(s)
- Marcela A Vidal
- Center for Ñuble Studies, Universidad del Bío-Bío, Av. Andrés Bello 720, Chillan 3800708, Chile
- Biodiversity and Global Change Research Group, Facultad de Ciencias, Universidad del Bío-Bío, Av. Andrés Bello 720, Chillan 3800708, Chile
| | - Nayadet Henríquez
- Biodiversity and Global Change Research Group, Facultad de Ciencias, Universidad del Bío-Bío, Av. Andrés Bello 720, Chillan 3800708, Chile
| | - Cristian Torres-Díaz
- Biodiversity and Global Change Research Group, Facultad de Ciencias, Universidad del Bío-Bío, Av. Andrés Bello 720, Chillan 3800708, Chile
| | - Gonzalo Collado
- Biodiversity and Global Change Research Group, Facultad de Ciencias, Universidad del Bío-Bío, Av. Andrés Bello 720, Chillan 3800708, Chile
| | - Ian S Acuña-Rodríguez
- Instituto de Investigación Interdisciplinaria (I3), Universidad de Talca, Campus Lircay, Avda, Lircay s/n, Talca 3465548, Chile
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3
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Collado GA, Torres-Díaz C, Vidal MA, Valladares MA. Genetic Diversity, Morphometric Characterization, and Conservation Reassessment of the Critically Endangered Freshwater Snail, Heleobia atacamensis, in the Atacama Saltpan, Northern Chile. Biology (Basel) 2023; 12:791. [PMID: 37372077 DOI: 10.3390/biology12060791] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 02/22/2023] [Accepted: 02/28/2023] [Indexed: 06/29/2023]
Abstract
Evaporitic ecosystems of the Atacama Desert contain a rich endemic fauna, including mollusk species. A recent study performed in the freshwater snail Heleobia atacamensis, endemic to the Atacama Saltpan, revealed a strong interdependence of genetic patterns with climatic fluctuations and landscape physiography. The species is currently listed as Critically Endangered at regional scale and as Data Deficient on the International Union for Conservation of Nature (IUCN) Red List. Here, we studied genetic diversity and demographic history of several populations of the species occurring on a connectivity gradient, including snails from new peripherical localities (Peine and Tilomonte), which were compared with topotype specimens. In addition, we reassessed the conservation status using the IUCN Red List categories and criteria considering species-specific idiosyncrasy. Phylogenetic and phylogeographical analyses indicated that snails from Peine and Tilomonte belong to H. atacamensis. We discovered significant differentiation in shell morphology, which was generally greater in geographically isolated populations. We also inferred six genetic clusters and a demographic expansion congruent with the wet periods that occurred at the end of the Pleistocene. Considering the highest risk category obtained, H. atacamensis was reassessed as Endangered at regional scale. Future conservation plans should consider the genetic assemblages as conservation units.
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Affiliation(s)
- Gonzalo A Collado
- Departamento de Ciencias Básicas, Facultad de Ciencias, Universidad del Bío-Bío, Avenida Andrés Bello 720, Chillán 3800708, Chile
- Grupo de Investigación en Biodiversidad y Cambio Global, Universidad del Bío-Bío, Avenida Andrés Bello 720, Chillán 3800708, Chile
| | - Cristian Torres-Díaz
- Departamento de Ciencias Básicas, Facultad de Ciencias, Universidad del Bío-Bío, Avenida Andrés Bello 720, Chillán 3800708, Chile
- Grupo de Investigación en Biodiversidad y Cambio Global, Universidad del Bío-Bío, Avenida Andrés Bello 720, Chillán 3800708, Chile
| | - Marcela A Vidal
- Departamento de Ciencias Básicas, Facultad de Ciencias, Universidad del Bío-Bío, Avenida Andrés Bello 720, Chillán 3800708, Chile
- Grupo de Investigación en Biodiversidad y Cambio Global, Universidad del Bío-Bío, Avenida Andrés Bello 720, Chillán 3800708, Chile
| | - Moisés A Valladares
- Departamento de Ciencias Básicas, Facultad de Ciencias, Universidad del Bío-Bío, Avenida Andrés Bello 720, Chillán 3800708, Chile
- Grupo de Investigación en Biodiversidad y Cambio Global, Universidad del Bío-Bío, Avenida Andrés Bello 720, Chillán 3800708, Chile
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4
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Cox N, Young BE, Bowles P, Fernandez M, Marin J, Rapacciuolo G, Böhm M, Brooks TM, Hedges SB, Hilton-Taylor C, Hoffmann M, Jenkins RKB, Tognelli MF, Alexander GJ, Allison A, Ananjeva NB, Auliya M, Avila LJ, Chapple DG, Cisneros-Heredia DF, Cogger HG, Colli GR, de Silva A, Eisemberg CC, Els J, Fong G A, Grant TD, Hitchmough RA, Iskandar DT, Kidera N, Martins M, Meiri S, Mitchell NJ, Molur S, Nogueira CDC, Ortiz JC, Penner J, Rhodin AGJ, Rivas GA, Rödel MO, Roll U, Sanders KL, Santos-Barrera G, Shea GM, Spawls S, Stuart BL, Tolley KA, Trape JF, Vidal MA, Wagner P, Wallace BP, Xie Y. A global reptile assessment highlights shared conservation needs of tetrapods. Nature 2022; 605:285-290. [PMID: 35477765 PMCID: PMC9095493 DOI: 10.1038/s41586-022-04664-7] [Citation(s) in RCA: 57] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 03/16/2022] [Indexed: 11/29/2022]
Abstract
Comprehensive assessments of species’ extinction risks have documented the extinction crisis1 and underpinned strategies for reducing those risks2. Global assessments reveal that, among tetrapods, 40.7% of amphibians, 25.4% of mammals and 13.6% of birds are threatened with extinction3. Because global assessments have been lacking, reptiles have been omitted from conservation-prioritization analyses that encompass other tetrapods4–7. Reptiles are unusually diverse in arid regions, suggesting that they may have different conservation needs6. Here we provide a comprehensive extinction-risk assessment of reptiles and show that at least 1,829 out of 10,196 species (21.1%) are threatened—confirming a previous extrapolation8 and representing 15.6 billion years of phylogenetic diversity. Reptiles are threatened by the same major factors that threaten other tetrapods—agriculture, logging, urban development and invasive species—although the threat posed by climate change remains uncertain. Reptiles inhabiting forests, where these threats are strongest, are more threatened than those in arid habitats, contrary to our prediction. Birds, mammals and amphibians are unexpectedly good surrogates for the conservation of reptiles, although threatened reptiles with the smallest ranges tend to be isolated from other threatened tetrapods. Although some reptiles—including most species of crocodiles and turtles—require urgent, targeted action to prevent extinctions, efforts to protect other tetrapods, such as habitat preservation and control of trade and invasive species, will probably also benefit many reptiles. An extinction-risk assessment of reptiles shows that at least 21.1% of species are threatened by factors such as agriculture, logging, urban development and invasive species, and that efforts to protect birds, mammals and amphibians probably also benefit many reptiles.
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Affiliation(s)
- Neil Cox
- Biodiversity Assessment Unit, IUCN-Conservation International, Washington, DC, USA
| | | | - Philip Bowles
- Biodiversity Assessment Unit, IUCN-Conservation International, Washington, DC, USA
| | - Miguel Fernandez
- NatureServe, Arlington, VA, USA.,Smithsonian-Mason School of Conservation and Department of Environmental Science and Policy, George Mason University, Fairfax, VA, USA.,Instituto de Ecología, Universidad Mayor de San Andrés, La Paz, Bolivia
| | - Julie Marin
- Université Sorbonne Paris Nord, INSERM, IAME, Bobigny, France
| | - Giovanni Rapacciuolo
- Institute for Biodiversity Science and Sustainability, California Academy of Sciences, San Francisco, CA, USA
| | - Monika Böhm
- Institute of Zoology, Zoological Society of London, London, UK
| | - Thomas M Brooks
- IUCN, Gland, Switzerland.,World Agroforestry Center (ICRAF), University of The Philippines, Los Baños, The Philippines.,Institute for Marine & Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
| | - S Blair Hedges
- Center for Biodiversity, Temple University, Philadelphia, PA, USA
| | - Craig Hilton-Taylor
- Science & Data Centre: Biodiversity Assessment & Knowledge Team, IUCN, Cambridge, UK
| | - Michael Hoffmann
- Conservation and Policy, Zoological Society of London, London, UK
| | - Richard K B Jenkins
- Science & Data Centre: Biodiversity Assessment & Knowledge Team, IUCN, Cambridge, UK
| | - Marcelo F Tognelli
- Biodiversity Assessment Unit, IUCN-Conservation International, Washington, DC, USA
| | - Graham J Alexander
- Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | | | - Natalia B Ananjeva
- Department of Herpetology, Zoological Institute, St Petersburg, Russian Federation
| | - Mark Auliya
- Department of Herpetology, Leibniz Institute for the Analysis of Biodiversity Change, Zoological Research Museum Alexander Koenig, Bonn, Germany
| | - Luciano Javier Avila
- Grupo Herpetología Patagónica (GHP-LASIBIBE), Instituto Patagónico para el Estudio de los Ecosistemas Continentales (IPEEC-CONICET), Puerto Madryn, Argentina
| | - David G Chapple
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia
| | - Diego F Cisneros-Heredia
- Colegio de Ciencias Biológicas y Ambientales, Museo de Zoología, Instituto de Biodiversidad Tropical iBIOTROP, Universidad San Francisco de Quito USFQ, Quito, Ecuador.,Instituto Nacional de Biodiversidad, Quito, Ecuador
| | - Harold G Cogger
- Australian Museum Research Institute, Sydney, New South Wales, Australia
| | - Guarino R Colli
- Departamento de Zoologia, Universidade de Brasília, Brasília, Brazil
| | - Anslem de Silva
- South Asia Regional Office, Crocodile Specialist Group, Gampols, Sri Lanka
| | | | - Johannes Els
- Environment and Protected Areas Authority, Government of Sharjah, Sharjah, United Arab Emirates
| | - Ansel Fong G
- Centro Oriental de Ecosistemas y Biodiversidad (BIOECO), Museo de Historia Natural "Tomás Romay", Santiago de Cuba, Cuba
| | - Tandora D Grant
- Conservation Science & Wildlife Health, San Diego Zoo Wildlife Alliance, San Diego, CA, USA
| | | | | | - Noriko Kidera
- Department of Biosphere-Geosphere Science, Okayama University of Science, Okayama, Japan.,National Institute for Environmental Studies, Tsukuba, Japan
| | - Marcio Martins
- Departamento de Ecologia, Universidade de São Paulo, São Paulo, Brazil
| | - Shai Meiri
- School of Zoology & the Steinhardt Museum of Natural History, Tel Aviv University, Tel Aviv, Israel
| | - Nicola J Mitchell
- School of Biological Sciences, The University of Western Australia, Crawley, Western Australia, Australia
| | | | | | - Juan Carlos Ortiz
- Departamento de Zoología, Universidad de Concepción, Concepción, Chile
| | - Johannes Penner
- Chair of Wildlife Ecology and Management, University of Freiburg, Freiburg, Germany.,Museum für Naturkunde - Leibniz Institute for Evolution and Biodiversity Science, Berlin, Germany
| | | | - Gilson A Rivas
- Museo de Biología, Universidad del Zulia, Maracaibo, Venezuela
| | - Mark-Oliver Rödel
- Museum für Naturkunde - Leibniz Institute for Evolution and Biodiversity Science, Berlin, Germany
| | - Uri Roll
- Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Israel
| | - Kate L Sanders
- University of Adelaide, Adelaide, South Australia, Australia
| | | | - Glenn M Shea
- Australian Museum Research Institute, Sydney, New South Wales, Australia.,Sydney School of Veterinary Science B01, University of Sydney, Sydney, New South Wales, Australia
| | | | - Bryan L Stuart
- Section of Research & Collections, North Carolina Museum of Natural Sciences, Raleigh, NC, USA
| | - Krystal A Tolley
- Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg, South Africa.,South African National Biodiversity Institute, Cape Town, South Africa
| | | | - Marcela A Vidal
- Departamento de Ciencias Básicas, Facultad de Ciencias, Universidad del Bío-Bío, Chillán, Chile
| | | | | | - Yan Xie
- Chinese Academy of Sciences, Beijing, China
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Navas CA, Gouveia SF, Solano-Iguarán JJ, Vidal MA, Bacigalupe LD. Amphibian responses in experimental thermal gradients: Concepts and limits for inference. Comp Biochem Physiol B Biochem Mol Biol 2021; 254:110576. [PMID: 33609807 DOI: 10.1016/j.cbpb.2021.110576] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 01/19/2021] [Accepted: 02/09/2021] [Indexed: 11/26/2022]
Abstract
The interpretation of thermal-gradient data depends on the behavioral drives reported or assumed, and on the underlying behavioral models explaining how such drives operate. The best-known example is positive thermotaxis, a thermoregulatory behavioral drive frequently linked to a dual set-point model of thermoregulation around a target range. This behavioral drive is often assumed as dominant among 'ectotherms', including amphibians. However, we argue that, because amphibians are extremely diverse, they may exhibit alternative behavioral drives in thermal gradients, and tackle this idea from two perspectives. First, we provide a historical review of original definitions and proposed limits for inference. Second, although caveats apply, we propose that a cross-study analysis of data of temperature settings of gradients and the temperatures selected by amphibians would corroborate alternative behavioral drives, including negative thermotaxis. Therefore, we analyzed published data focusing on such relationships and show that gradient temperature settings influence the temperatures selected by amphibians, with further effects of phylogeny and ontogeny. We conclude that thermal gradient experiments are outstanding tools to investigate behavioral drives, but no given drive can be assumed a priori unless additional information about thermoregulation is available. Based on the historical debate, we propose using selected temperatures and preferred temperatures as different concepts, the former merely operational and the second explicitly linked to positive thermotaxis (and thus compatible with dual set-point thermoregulation). Under this view, thermal preferences would stand for a hypothesis of a behavioral drive (positive thermotaxis) requiring formal testing. These considerations impact the scope for inference based on thermal gradient experiments, particularly ecological modeling and emerging disease.
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Affiliation(s)
- Carlos A Navas
- Department of Physiology, Biosciences Institute, University of São Paulo, Brazil.
| | - Sidney F Gouveia
- Departament of Ecology, Federal University of Sergipe, São Cristóvão, Brazil
| | - Jaiber J Solano-Iguarán
- Institute of Environmental and Evolutionary Sciences, Austral University of Chile, Isla Teja Campus, Valdivia, Chile
| | - Marcela A Vidal
- Departament of Basic Sciences, Faculty of Sciences, Bío-Bío University, Casilla 447, Chillán, Chile
| | - Leonardo D Bacigalupe
- Institute of Environmental and Evolutionary Sciences, Austral University of Chile, Isla Teja Campus, Valdivia, Chile
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6
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Collado GA, Vidal MA, Torres-DÍaz C, Cabrera FJ, Araya JF, Darrigran G. Morphological and molecular identification of the invasive freshwater snail Physa acuta (Gastropoda: Physidae) into Llanquihue Lake, Chilean Patagonia. AN ACAD BRAS CIENC 2020; 92:e20181101. [PMID: 33146259 DOI: 10.1590/0001-3765202020181101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 01/31/2019] [Indexed: 11/22/2022] Open
Abstract
The sewage snail Physa acuta, native to North America, is an effective invasive species around the world. In Chile, it was first reported in 2014 in the north central area of the country. So far, the species has not been recorded in southern Chile. Sampling performed in 2015 in three localities from Llanquihue Lake, Chilean Patagonia, only provided native freshwater snails. However, new collections performed in February 2018 in the same three sites were successful for physid specimens suggesting a biological invasion entailing a large southward range expansion of these snails. Here we performed morphological, microstructural and phylogenetic analyses to investigate whether the new samples belong to Physa acuta. The shell morphology, male copulatory complex and radula microstructure of the new material agree with those of the sewage snail. The molecular phylogenetic analyses using the cytochrome c oxidase subunit 1 (COI) gene confirmed morphological identification. We suggest to take prompt measures to prevent the expansion of Physa acuta in Llanquihue Lake or nearby aquatic ecosystems.
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Affiliation(s)
- Gonzalo A Collado
- Universidad del Bío-Bío, Facultad de Ciencias, Departamento de Ciencias Básicas, Avenida Andrés Bello, 720, Chillán, Chile.,Universidad del Bío-Bío, Grupo de Investigación Biodiversidad y Cambio Global, Avenida Andrés Bello, 720, Chillán, Chile
| | - Marcela A Vidal
- Universidad del Bío-Bío, Facultad de Ciencias, Departamento de Ciencias Básicas, Avenida Andrés Bello, 720, Chillán, Chile.,Universidad del Bío-Bío, Grupo de Investigación Biodiversidad y Cambio Global, Avenida Andrés Bello, 720, Chillán, Chile
| | - Cristian Torres-DÍaz
- Universidad del Bío-Bío, Facultad de Ciencias, Departamento de Ciencias Básicas, Avenida Andrés Bello, 720, Chillán, Chile.,Universidad del Bío-Bío, Grupo de Investigación Biodiversidad y Cambio Global, Avenida Andrés Bello, 720, Chillán, Chile
| | - Francisco J Cabrera
- Universidad Tecnológica de Chile INACAP, Longitudinal Sur 441, Chillán, Chile
| | - Juan F Araya
- Universidad de Atacama, Centro de Investigaciones Costeras/CIC-UDA, Copayapu 485, Copiapó, Chile
| | - Gustavo Darrigran
- División Zoología Invertebrados, Museo de La Plata, FCNyM-UNLP, CONICET, Paseo del Bosque, 1900 La Plata, Argentina
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Vidal MA, Barría-Oyarzo I, Contreras C, Bacigalupe LD. Geography, Temperature, and Water: Interaction Effects in a Small Native Amphibian. Physiol Biochem Zool 2020; 93:369-375. [PMID: 32762608 DOI: 10.1086/710537] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Amphibian locomotor capacity is strongly linked to temperature and hydration. However, organisms in nature experience covariation of multiple environmental factors, and thus to better understand the effects of thermal and hydric conditions on physiological performance, it is critical not only to experimentally disentangle them but also to incorporate potential interactive effects due to geographic variation. To this end, we selected two populations of the small amphibian Pleurodema thaul inhabiting highly contrasting temperatures and precipitation regimens. With these two populations, we evaluated the thermal and hydric sensitivities of locomotor performance. For both factors, performance increased with temperature as well as with hydration level, although performance reached a plateau between 25° and 30°C. In addition, the influence of dehydration on performance was independent of the temperature at which it was tested. Our results also showed that the population from the warmer environment has lower sensitivity of locomotor performance to dehydration, probably as a consequence of thermal adaptation, although further studies might be required to fully understand this.
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8
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Vidal MA, Novoa-Muñoz F, Werner E, Torres C, Nova R. Modeling warming predicts a physiological threshold for the extinction of the living fossil frog Calyptocephalella gayi. J Therm Biol 2017; 69:110-117. [DOI: 10.1016/j.jtherbio.2017.07.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 07/01/2017] [Accepted: 07/01/2017] [Indexed: 01/07/2023]
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9
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Vidal MA, Ibáñez S, Moreno PI, Poulin E. Phylogeography of a Patagonian lizard and frog: Congruent signature of southern glacial refuges. AUSTRAL ECOL 2016. [DOI: 10.1111/aec.12325] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Marcela A. Vidal
- Department of Basic Sciences, Faculty of Science; Universidad del Bío-Bío; Chillan
| | - Soledad Ibáñez
- Department of Basic Sciences, Faculty of Science; Universidad del Bío-Bío; Chillan
| | - Patricio I. Moreno
- Institute of Ecology and Biodiversity, Department of Ecological Sciences, Faculty of Science; Universidad de Chile; Santiago Chile
| | - Elie Poulin
- Institute of Ecology and Biodiversity, Department of Ecological Sciences, Faculty of Science; Universidad de Chile; Santiago Chile
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10
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Flores-Cedillo ML, Alvarado-Estrada KN, Pozos-Guillén AJ, Murguía-Ibarra JS, Vidal MA, Cervantes-Uc JM, Rosales-Ibáñez R, Cauich-Rodríguez JV. Multiwall carbon nanotubes/polycaprolactone scaffolds seeded with human dental pulp stem cells for bone tissue regeneration. J Mater Sci Mater Med 2016; 27:35. [PMID: 26704552 DOI: 10.1007/s10856-015-5640-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 11/27/2015] [Indexed: 06/05/2023]
Abstract
Conventional approaches to bone regeneration rarely use multiwall carbon nanotubes (MWCNTs) but instead use polymeric matrices filled with hydroxyapatite, calcium phosphates and bioactive glasses. In this study, we prepared composites of MWCNTs/polycaprolactone (PCL) for bone regeneration as follows: (a) MWCNTs randomly dispersed on PCL, (b) MWCNTs aligned with an electrical field to determine if the orientation favors the growing of human dental pulp stem cells (HDPSCs), and (c) MWCNTs modified with β-glycerol phosphate (BGP) to analyze its osteogenic potential. Raman spectroscopy confirmed the presence of MWCNTs and BGP on PCL, whereas the increase in crystallinity by the addition of MWCNTs to PCL was confirmed by X-ray diffraction and differential scanning calorimetry. A higher elastic modulus (608 ± 4.3 MPa), maximum stress (42 ± 6.1 MPa) and electrical conductivity (1.67 × 10(-7) S/m) were observed in non-aligned MWCNTs compared with the pristine PCL. Cell viability at 14 days was similar in all samples according to the live/dead assay, but the 21 day cell proliferation, measured by MTT was higher in MWCNTs aligned with BGP. Von Kossa and Alizarin red showed larger amounts of mineral deposits on MWCNTs aligned with BGP, indicating that at 21 days, this scaffold promotes osteogenic differentiation of HDPSCs.
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Affiliation(s)
- M L Flores-Cedillo
- Facultad de Estomatología, Laboratorio de Ciencias Básicas, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
| | - K N Alvarado-Estrada
- Facultad de Estomatología, Laboratorio de Ciencias Básicas, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
| | - A J Pozos-Guillén
- Facultad de Estomatología, Laboratorio de Ciencias Básicas, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
| | - J S Murguía-Ibarra
- Facultad de Ciencias, Departamento de Electrónica, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
| | - M A Vidal
- Centro de Aplicación de Radiación Infrarroja, Energías Alternativas y Materiales, CIACYT, San Luis Potosí, Mexico
| | - J M Cervantes-Uc
- Centro de Investigación Científica de Yucatán, Unidad de Materiales, Mérida, Yucatán, Mexico
| | - R Rosales-Ibáñez
- Facultad de Estomatología, Laboratorio de Ciencias Básicas, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
| | - J V Cauich-Rodríguez
- Centro de Investigación Científica de Yucatán, Unidad de Materiales, Mérida, Yucatán, Mexico.
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Knych HK, Vidal MA, Chouicha N, Mitchell M, Kass PH. Cytokine, catabolic enzyme and structural matrix gene expression in synovial fluid following intra-articular administration of triamcinolone acetonide in exercised horses. Equine Vet J 2016; 49:107-115. [PMID: 26518341 DOI: 10.1111/evj.12531] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 10/17/2015] [Indexed: 01/07/2023]
Abstract
REASON FOR PERFORMING STUDY The frequent use of intra-articular triamcinolone acetonide (TA) in performance horses warrants further study of the duration of as well as the beneficial and detrimental effects on gene expression associated with administration. OBJECTIVES To assess the effects of intra-articular administration of TA on the expression of selected anti- and proinflammatory and structural matrix genes following its administration into joints of exercised Thoroughbred horses and to correlate these effects with plasma and synovial fluid drug concentrations. STUDY DESIGN Block design experiment. METHODS Eight exercised horses received a single intra-articular administration of 9 mg of TA. Synovial fluid samples were collected from the treated and contralateral joints prior to and up to 49 days following drug administration. Microarray and quantitative reverse transcription polymerase chain reaction analysis were used to assess changes in expression levels of various inflammatory and structural genes post drug administration. RESULTS Drug concentrations in plasma and synovial fluid, were no longer quantifiable by 6 and 28 days following drug administration respectively. In total, the expression level of 5490 genes were significantly altered on micro array analysis, following intra-articular TA administration. Of the genes selected for further study by quantitative reverse transcription polymerase chain reaction analysis, significant changes in inflammatory genes (annexin type 1, cyclooxygenase-1 and tumour necrosis factor stimulated gene 6) and structural genes (collagen and aggrecan) were noted. CONCLUSIONS This study supports the use of synovial fluid as a biological matrix for studying the effects of corticosteroids on gene expression. For the majority of genes studied the effects on expression relative to baseline for both inflammatory and matrix genes were prolonged relative to plasma and synovial fluid TA concentrations. Downregulation of collagen gene expression warrants the careful use of TA in horses.
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Affiliation(s)
- H K Knych
- K.L. Maddy Equine Analytical Chemistry Laboratory, School of Veterinary Medicine, University of California, Davis, USA.,Department of Veterinary Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, USA
| | - M A Vidal
- Department of Surgery and Radiology, School of Veterinary Medicine, University of California, Davis, USA
| | - N Chouicha
- K.L. Maddy Equine Analytical Chemistry Laboratory, School of Veterinary Medicine, University of California, Davis, USA
| | - M Mitchell
- K.L. Maddy Equine Analytical Chemistry Laboratory, School of Veterinary Medicine, University of California, Davis, USA
| | - P H Kass
- Department of Health and Reproduction, School of Veterinary Medicine, University of California, Davis, USA
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Trela JM, Spriet M, Padgett KA, Galuppo LD, Vaughan B, Vidal MA. Scintigraphic comparison of intra-arterial injection and distal intravenous regional limb perfusion for administration of mesenchymal stem cells to the equine foot. Equine Vet J 2013; 46:479-83. [PMID: 23834199 DOI: 10.1111/evj.12137] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 06/29/2013] [Indexed: 12/26/2022]
Abstract
REASONS FOR PERFORMING STUDY Intra-arterial (i.a.) and intravenous (i.v.) regional limb perfusions (RLP) through the median artery and cephalic vein, respectively, have been previously investigated for administration of mesenchymal stem cells (MSCs) to the equine distal limb. Limitations due to thrombosis of the arteries after i.a. RLP and poor distribution of MSCs to the foot with i.v. RLP were observed. These techniques need to be modified for clinical use. OBJECTIVES Evaluate the distribution, uptake and persistence of radiolabelled MSCs after i.a. injection through the median artery without a tourniquet and after i.v. RLP through the lateral palmar digital vein. STUDY DESIGN In vivo experimental study. METHODS (99m) Tc-HMPAO-labelled MSCs were injected through the median artery of one limb and the lateral palmar digital vein of the other limb of 6 horses under general anaesthesia. No tourniquet was used for the i.a. injection. A pneumatic tourniquet was placed on the metacarpus for i.v. injection. Scintigraphic images were obtained up to 24 h after injection. RESULTS Intra-arterial injection resulted in MSCs retention within the limb despite the absence of a tourniquet and no thrombosis was observed. Both i.a. injection and i.v. RLP led to distribution of MSCs to the foot. The i.a. injection resulted in a more homogeneous distribution. The MSC uptake was higher with i.v. RLP at the initial timepoints, but no significant difference was present at 24 h. CONCLUSIONS Both i.a. injection through the median artery without a tourniquet and i.v. RLP performed through the lateral palmar digital vein under general anaesthesia are safe and reliable methods for administration of MSCs to the equine foot. The i.a. technique is preferred owing to the better distribution, but is technically more challenging. The feasibility of performing these techniques on standing horses remains to be investigated.
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Affiliation(s)
- J M Trela
- Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California, Davis, USA
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Sole A, Spriet M, Padgett KA, Vaughan B, Galuppo LD, Borjesson DL, Wisner ER, Vidal MA. Distribution and persistence of technetium-99 hexamethyl propylene amine oxime-labelled bone marrow-derived mesenchymal stem cells in experimentally induced tendon lesions after intratendinous injection and regional perfusion of the equine distal limb. Equine Vet J 2013; 45:726-31. [PMID: 23574488 DOI: 10.1111/evj.12063] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2012] [Accepted: 01/27/2013] [Indexed: 12/25/2022]
Abstract
REASONS FOR PERFORMING STUDY Intralesional (i.l.) injection is currently the most commonly used technique for stem cell therapy in equine tendon injury. A comparison of different techniques of injection of mesenchymal stem cells for the treatment of tendon lesions is required. OBJECTIVES We hypothesised that vascular perfusion of the equine distal limb with mesenchymal stem cells (MSCs) would result in preferential distribution of MSCs to acute tendon injuries. STUDY DESIGN In vivo experimental study. METHODS Lesions were surgically induced in forelimb superficial digital flexor tendons of 8 horses. Three or 10 days after lesion induction, technetium-99 hexamethyl propylene amine oxime-labelled MSCs were injected via i.v. or intra-arterial (i.a.) regional limb perfusion (RLP) at the level of the distal antebrachium and compared to i.l. injection. Mesenchymal stem cell persistence and distribution within the forelimb and tendon lesions was assessed with scintigraphy for 24 h. RESULTS Lesion uptake was higher with i.l. injection than with RLP, but MSC persistence decreased similarly over time in all 3 techniques. Intra-arterial RLP resulted in a better distribution of MSCs and a higher uptake at the lesion site than i.v. RLP. Limbs perfused i.a. on Day 10 showed greater accumulation of MSCs in the lesion than limbs perfused on Day 3. Arterial thrombosis occurred in 50% of the i.v. RLP limbs and in 100% of the i.a. RLP limbs, which led to clinical complications in one horse. CONCLUSIONS AND POTENTIAL RELEVANCE Compared with i.l. injection, RLP results in lower uptake but similar persistence of MSCs at the site of tendon lesions. A time dependent accumulation of MSCs was identified with i.a. RLP. The i.a. RLP appears more advantageous than the i.v. RLP in terms of distribution and uptake. However, the described i.a. technique produced arterial thrombosis and thus cannot currently be recommended for clinical use.
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Affiliation(s)
- A Sole
- Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California, USA
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Vidal MA, Ortiz JC, Marín JC, Poulin E, Moreno PI. Comparative phylogeography of two co-distributed species of lizards of the genus Liolaemus (Squamata: Tropiduridae) from Southern Chile. AMPHIBIA-REPTILIA 2012. [DOI: 10.1163/156853811x622039] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Comparative phylogeography describes the patterns of evolutionary divergence and whether or not they are congruent, in co-distributed populations of different taxa. If the populations of these taxa have been co-distributed for a prolonged time, and if the times between processes of perturbation or vicariance have been more or less stable, it is expected that patterns of divergence will be congruent in closely related species, for example because of similar biological and demographic characteristics.Liolaemus pictusandL. cyanogasterare widely co-distributed lizard species in southern Chile, occurring in a region with a complex topology. We analyzed the phylogeographic structure of the two lizard species usingCytochromebDNA sequences to estimate their genetic structure in response to historical events. Our results suggest an evolutionary pattern of genetic diversity for each species that is consistent with the geomorphological history of the region, suggesting a complex phylogeographic history inLiolaemusspecies. Also, the high levels of divergence among haplotypes in several populations suggest the possibility that their origin might predate the middle Pleistocene in both species. Finally, our results are consistent with our hypothesis that two species have responded to historical events in parallel, where historical process have been sufficient to influence their phylogeographical structure (0.80 congruency between topologies).
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Affiliation(s)
- Marcela A. Vidal
- 1Laboratorio de Genómica y Biodiversidad, Departamento de Ciencias Básicas, Facultad de Ciencias, Universidad del Bío-Bío, Casilla 447, Chillán, Chile
| | - Juan Carlos Ortiz
- 2Departamento de Zoología, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Casilla 160-C, Concepción, Chile
| | - Juan Carlos Marín
- 1Laboratorio de Genómica y Biodiversidad, Departamento de Ciencias Básicas, Facultad de Ciencias, Universidad del Bío-Bío, Casilla 447, Chillán, Chile
| | - Elie Poulin
- 3Instituto de Ecología y Biodiversidad, Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile
| | - Patricio I. Moreno
- 3Instituto de Ecología y Biodiversidad, Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile
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Vera-Reveles G, Simmons TJ, Bravo-Sánchez M, Vidal MA, Navarro-Contreras H, González FJ. High-sensitivity bolometers from self-oriented single-walled carbon nanotube composites. ACS Appl Mater Interfaces 2011; 3:3200-3204. [PMID: 21749106 DOI: 10.1021/am2007036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In this work, films of horizontally aligned single-walled carbon nanotubes were thermally and electrically characterized in order to determine the bolometric performance. An average thermal time constant of τ = 420 μs along with a temperature coefficient of resistance of TCR = -2.94% K(-1) were obtained. The maximum voltage responsivity and detectivity obtained were R(V) =230 V/W and D* = 1.22 × 10(8) cm Hz(1/2)/W, respectively. These values are higher than the maximum voltage responsivity (150 V/W) and maximum temperature coefficient of resistance (1.0% K(-1)) previously reported for carbon nanotube films at room temperature. The maximum detectivity was obtained at a frequency of operation of 1.25 kHz.
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Affiliation(s)
- Gustavo Vera-Reveles
- Coordinación para la Innovación y la Aplicación de la Ciencia y la Tecnología, Universidad Autónoma de San Luis Potosí, San Luis Potosí 78000, México
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Vidal MA, Sabat P. Stable isotopes document mainland–island divergence in resource use without concomitant physiological changes in the lizard Liolaemus pictus. Comp Biochem Physiol B Biochem Mol Biol 2010; 156:61-7. [DOI: 10.1016/j.cbpb.2010.02.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2009] [Revised: 02/07/2010] [Accepted: 02/16/2010] [Indexed: 10/19/2022]
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Vidal MA, Habit E, Victoriano P, González-Gajardo A, Ortiz JC. Thermoregulation and activity pattern of the high-mountain lizard Phymaturus palluma (Tropiduridae) in Chile. Zoologia (Curitiba, Impr ) 2010. [DOI: 10.1590/s1984-46702010000100003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Vidal MA, Ortiz JC. Amphibia, Anura, Ceratophryidae, Batrachyla leptopus Bell, 1843: insular distribution extension, Chile. cl 2009. [DOI: 10.15560/5.4.869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Abstract
Abstract
We analyze the geographic distribution pattern of Chilean amphibian and
reptile species between 18°20′S (Arica) to 56°S (Magellanic Area) by the
identification of centers of higher richness and endemism and we infer the
biological processes that could have promoted these patterns from a
biogeographic point of view, comparing our results with the present location
of National Parks found in the National System of State Wildlife Protected
Areas. Our results provide evidence that richness and endemism shows clear
latitudinal trends along Chile, with highest values at mid-latitudes (31°S
to 44°S). Five areas of endemism for phenetic analysis and six for PAE
(Parsimony analysis of endemism) were found that agree with bioclimatic
boundaries. We suggest that the richness and endemism patterns registered
for Chilean herpetological taxa may be explained by an historical mechanism,
in accordance with previous biogeographical proposals. To improve the
conservation efforts for amphibians and reptiles we suggest inclusion of new
protected areas at the regional level for the Mediterranean region of
south-central Chile and for local northern and southern quadrats with high
species richness and endemism.
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Affiliation(s)
- Marcela A. Vidal
- 2Laboratorio de Genómica y Biodiversidad (LGB), Departamento de Ciencias Básicas, Facultad de Ciencias, Universidad del Bío-Bío, Casilla 447, Chillán, Chile, Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Santiago, Chile;,
| | - Eduardo R. Soto
- 1Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Santiago, Chile
| | - Alberto Veloso
- 3Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Santiago, Chile
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Matus CE, Ehrenfeld P, Pavicic F, Sarmiento JM, Astroza A, Sanchez T, Salem C, Concha M, Vidal MA, Gonzalez CB, Figueroa CD. Activation of kinin B receptor triggers differentiation of cultured human keratinocytes. Br J Dermatol 2008; 159:792-803. [PMID: 18717683 DOI: 10.1111/j.1365-2133.2008.08784.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
BACKGROUND Keratinocyte life span is modulated by receptors that control proliferation and differentiation, key processes during cutaneous tissue repair. The kinin B(1) receptor (B(1)R) has been reported in normal and pathological human skin, but so far there is no information about its role in keratinocyte biology. OBJECTIVES To determine the consequence of kinin B(1)R stimulation on tyrosine phosphorylation, a key signalling mechanism involved in keratinocyte proliferation and differentiation. METHODS Subconfluent primary cultures of human keratinocytes were used to investigate tyrosine phosphorylation, epidermal growth factor receptor (EGFR) transactivation, cell proliferation and keratinocyte differentiation. Cell proliferation was assessed by measuring bromodeoxyuridine incorporation whereas assessment of cell differentiation was based on the expression of filaggrin, cytokeratin 10 (CK10) and involucrin. RESULTS The major proteins phosphorylated, after B(1)R stimulation, were of molecular mass 170, 125, 89 and 70 kDa. The 170- and 125-kDa proteins were identified as EGFR and p125(FAK), respectively. Phosphorylation was greatly reduced by GF109203X and by overexposure of keratinocytes to phorbol 12-myristate 13-acetate, indicating the participation of protein kinase C. B(1)R stimulation did not increase [Ca(2+)]i, but triggered EGFR transactivation, an event that involved phosphorylation of Tyr(845), Tyr(992) and Tyr(1068) of EGFR. B(1)R stimulation did not elicit keratinocyte proliferation, but triggered cell differentiation, visualized as an increase of filaggrin, CK10 and involucrin. Blockade of EGFR tyrosine kinase by AG1478, before B(1)R stimulation, produced an additional increase in filaggrin expression. CONCLUSIONS The kinin B(1)R may contribute to keratinocyte differentiation and migration by triggering specific tyrosine signalling pathways or by interacting with the ErbB receptor family.
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Affiliation(s)
- C E Matus
- Laboratorio de Patologia Celular, Instituto de Anatomía, Histología y Patología, Universidad Austral de Chile, Casilla 567, Isla Teja, Valdivia, Chile
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Vidal MA, Torres LM. [Mild to moderate postoperative pain: the PATHOS survey results for Spain versus other European countries]. Rev Esp Anestesiol Reanim 2008; 55:393-400. [PMID: 18853676 DOI: 10.1016/s0034-9356(08)70609-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
OBJECTIVES The Postoperative Analgesic Therapy Observational Survey (PATHOS) was designed to identify the current state of postoperative pain in specific areas and the needs and opportunities for improving treatment. We compared the results obtained in Spain with those obtained in the rest of Europe between August 2004 and June 2005. MATERIAL AND METHODS A prospective observational multicenter, multinational study in 7 European countries. The data on postoperative pain management were obtained anonymously by means of a standardized multiple-choice questionnaire. RESULTS Participation was higher among surgeons (68%) in Spain and among anesthesiologists (69%) in other European countries. Systematic presurgical information on the treatment of postoperative pain was provided to 22.2% of patients undergoing surgery in Spain. Organized structures for the treatment of postoperative pain are less common in Spanish hospitals (47%) than in other European hospitals (69%). Anesthesiologists are less often those who inform patients about postoperative pain in Spain than in other European countries. Only 25.9% of Spanish hospitals have written protocols for treating postoperative pain. Pain was not evaluated in 39% of patients who underwent surgery in Spain. CONCLUSIONS There is inadequate treatment of postoperative pain, and the problem is greater in Spain than in the other European countries participating in PATHOS. The results should help to identify opportunities for improvement.
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Affiliation(s)
- M A Vidal
- Servicio de Anestesiologá, Hospital Universitario Puerta del Mar, Cádiz.
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Sepúlveda M, Vidal MA, Fariña JM, Sabat P. Seasonal and geographic variation in thermal biology of the lizard Microlophus atacamensis (Squamata: Tropiduridae). J Therm Biol 2008. [DOI: 10.1016/j.jtherbio.2007.07.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Vidal MA, Calderón E, Martínez E, Pernia A, Torres LM. [Comparison of 2 techniques for inhaled anesthetic induction with sevoflurane in coronary artery revascularization]. Rev Esp Anestesiol Reanim 2006; 53:639-42. [PMID: 17302078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
OBJECTIVE Our objective was to evaluate efficacy, side effects, and hemodynamic alterations during anesthetic induction with sevoflurane in patients undergoing coronary artery bypass surgery, comparing the techniques of administration with tidal volume breathing and with vital capacity breaths. MATERIAL AND METHODS This was a randomized controlled trial enrolling 30 patients scheduled for myocardial revascularization. Anesthetic induction with inhaled sevoflurane was performed with 2 techniques: sevoflurane administered with tidal volume breathing (n=15) and with vital capacity breaths (n=15). We assessed time until a bispectral index (BIS) of 50 or less was reached. We also recorded adverse effects and alterations in hemodynamic variables during induction. RESULTS The time to induction was significantly shorter in the tidal volume group. The time until reaching a BIS of 50 or less was significantly shorter in the vital capacity group. Hemodynamics were similar in both groups (no significant differences). In both groups mean arterial pressure decreased significantly from baseline (P<0.05) and systolic and diastolic blood pressures both decreased slightly, with no significant heart rate or ST segment changes. Adverse effects were few and not serious. CONCLUSIONS Mean arterial pressure decreased in both groups, with no significant differences. The results indicate that hemodynamic stability seems to be similar with both techniques for providing inhaled anesthetic induction with sevoflurane.
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Affiliation(s)
- M A Vidal
- Departamento de Anestesia, Reanimación y Unidad del Dolor, Hospital Universitario Puerta del Mar, Cádiz.
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Vidal MA, Calderón E, Pernia A, Calderón-Pla E, Torres LM. [Transdermal buprenorphine and silent acute coronary syndrome]. Rev Esp Anestesiol Reanim 2006; 53:58-9. [PMID: 16475644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
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Vidal MA, Sebastianes C, Eizaga R, Martínez E, Torres LM. [Activated recombinant factor VII for bleeding after a kidney transplant]. Rev Esp Anestesiol Reanim 2005; 52:638-9. [PMID: 16435622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
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Vidal MA, López-Escobar M, Medina C, García R, Torres LM. [Hypovolemic shock during surgery caused by a rectus sheath hematoma]. Rev Esp Anestesiol Reanim 2005; 52:495-8. [PMID: 16281745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Prophylactic treatment with low molecular weight heparins (LMWH) is currently widely used to prevent thromboembolic events. However, such treatment is not free of risk. Among the possible complications described is rectus sheath hematoma. We report the case of a patient undergoing surgery for a hypophysial adenoma approached by the transsphenoidal route. He received LMWH prophylaxis for thromboembolism and showed a tendency to hypotension during surgery. The patient's condition deteriorated to hypovolemic shock accompanied by episodes of atrial fibrillation with rapid ventricular response. With the transfusion of medications, blood products and plasma volume expanders, the patient was stabilized and surgery was completed. A computed tomography scan then revealed a hematoma occupying the greater part of the left anterior rectus muscle. With conservative wait-and-see treatment the abdominal symptoms disappeared and the hematoma gradually receded until fully resolved. Spontaneous rectus sheath hematoma is a rare condition. Presentation is quite nonspecific and computed tomography is needed for reaching a firm diagnosis. When a hematoma is large, the initial clinical picture may include hypovolemic shock, which may develop during surgery if the hematoma is not diagnosed early. Intraoperative management will be much more difficult than it would have been if diagnosis and treatment had taken place before the operation.
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Affiliation(s)
- M A Vidal
- Servicio de Anestesiología, Reanimación y Tratamiento del Dolor, Hospital Universitario Puerta del Mar, Cádiz
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Vidal MA, Velázquez A, Morgado I, Pérez Bustamante F, Torres LM. [Sedation with remifentanil for tracheostomy in a pediatric patient]. Rev Esp Anestesiol Reanim 2004; 51:600-3. [PMID: 15641606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
Remifentanil is an ultra-short-acting opioid that is frequently used in adults for surgical anesthesia or conscious sedation, but its use in children is much less common. We report the case of a 7-year-old boy with lateral cervical tumors displacing all cervical and facial structures. An emergency tracheostomy was performed when he developed respiratory difficulty due to partial airway obstruction. Because of the size and location of the intraoral tumors and a history of bleeding, orotracheal intubation and other airway management techniques were ruled out. The tracheostomy was performed under local anesthesia and sedation with a perfusion of 0.05 x microgKg(-1) x min(-1) provided the necessary relaxation and immobility for surgery. Sedation under observation with monitoring is among the indications of remifentanil. Spontaneous breathing is maintained with infusions less than 0.05 to 0.1 microg x Kg(-1) x min(-1). In the case we report, the patient's risk of complete airway obstruction due to bleeding upon manipulation had to be assessed and compared with the respiratory depression that might possibly have been caused by remifentanil perfusion. We judged that the option of sedation would cause less morbidity and offered greater safety for the patient. The outcome of this case is consistent with reports that remifentanil is a good option for adequately sedating children who are breathing spontaneously.
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Affiliation(s)
- M A Vidal
- Departamento de Anestesia, Reanimación y Unidad del Dolor. Hospital Universitario. Puerta del Mar. Cádiz
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Schröder H, Marrugat J, Covas M, Elosua R, Pena A, Weinbrenner T, Fito M, Vidal MA, Masia R. Population dietary habits and physical activity modification with age. Eur J Clin Nutr 2004; 58:302-11. [PMID: 14749751 DOI: 10.1038/sj.ejcn.1601782] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE The aim of the present study was to analyse the relation between age and both dietary habits and leisure-time physical activity, and to determine nutrient inadequacy of aged groups in our population. DESIGN Cross-sectional study. SETTING A random sample of the 25-74-y-old population of Gerona, Spain. SUBJECTS A total of 838 men and 910 women were selected from among the general population according to the 1991 census. OUTCOME MEASURES Analysis of dietary habits, including amount and type of alcohol consumption, and detailed evaluation of leisure-time physical activity. RESULTS Nutrient densities of carbohydrates, vitamin B(1), vitamin B(12), vitamin C, vitamin E, folate, potassium, iron, magnesium, copper, and dietary fiber increased significantly (P<0.05) with age in both genders, whereas an inverse trend was observed for total fat, saturated fatty acids, cholesterol, and sodium. Multiple linear regression analysis revealed a direct association of healthy dietary habits, characterized through a composite dietary score, with age after adjusting for several confounders both in men and women (P<0.001). This score was composed of folate, vitamin C, vitamin E, beta-carotene, dietary fibre, cholesterol, saturated fatty acids, and sodium. In all, 29 and 10% of male and female subjects aged 65-74 y, respectively, reported inadequate intakes of six or more of 16 nutrients. Total leisure-time physical activity increased with age in men (P<0.002), and was not different among female age groups. CONCLUSION Dietary behaviours and levels of physical activity spent during leisure time indicate a healthy lifestyle of the aged men and women in the present population. Nutrient inadequacy observed in some aged men and women, however, deserves particular intervention of health-care programmes for this growing part of our society.
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Affiliation(s)
- H Schröder
- Lipids and Cardiovascular Epidemiology Unit, Institut Municipal d'Investigació Mèdica, IMIM, Barcelona, Spain.
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Vidal MA, Ortiz JC. ANALISIS OSTEOLOGICO EN DOS ESPECIES DE MICROLOPHUS (SAURIA, TROPIDURIDAE) DE LA COSTA CHILENO-PERUANA. Gayana (Concepc ) 2004. [DOI: 10.4067/s0717-65382004000100002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Concha M, Vidal MA, Moreno I, Salem C, Figueroa CD, Schmitt D, Péguet-Navarro J. Evidence for modulation of human epidermal differentiation and remodelling by CD40. Br J Dermatol 2003; 148:1105-14. [PMID: 12828736 DOI: 10.1046/j.1365-2133.2003.05300.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND It is widely accepted that CD40 plays a critical role in the regulation of immune response. However, the significance of CD40 expression on normal human keratinocytes is only partially known. OBJECTIVES To perform a morphological re-examination of the role of CD40 on the differentiation of human keratinocytes and remodelling of the epidermis. METHODS Keratinocytes were grown on fibroblasts transfected with the CD40 ligand (CD40L) to investigate the formation of epidermal sheets in culture under the influence of the CD40L. Control experiments were carried out using the same cells but transfected with CD32. Further, three specific anti-CD40 monoclonal antibodies were used as soluble agonists to analyse the effect of CD40 ligation on keratinocyte differentiation. RESULTS Epidermal sheets developing from keratinocytes cocultured with fibroblasts transfected with CD40L but not with CD32 showed an up to 50% reduction in thickness compared with control sheets. This change depended mostly on cellular flattening and a decrease in the number of cell layers, and was coincident with a transient decrease in cell surface CD40 immunoreactivity. On the other hand, normal epidermis, and freshly isolated and cultured keratinocytes revealed a predominant CD40+/Ki-67- phenotype that was demonstrated by double immunocytochemistry. Consistent with these observations, keratinocytes primed with interferon-gamma responded to the three soluble agonists, but not to control IgG1, producing immunoreactive (pro)filaggrin and displaying morphological changes in shape and size equivalent to those seen in differentiated cells. CONCLUSIONS As a whole, our findings provide evidence that CD40+ keratinocytes represent a poorly differentiated population, not actively engaged in the cell cycle, which under specific stimulation is committed towards terminal differentiation.
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Affiliation(s)
- M Concha
- Institutos de Histología y Patología, Especialidades and Cirugía, Facultad de Medicina, Universidad Austral de Chile, Cas 567, Valdivia, Chile INSERM U346, Hôpital Ed Herriot, Lyon, France
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31
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Iglesias LA, López-Lopategui MC, Almagro F, Beristain X, Vidal MA. [Endocarditis due to Gemella haemolysans]. Enferm Infecc Microbiol Clin 1999; 17:538-9. [PMID: 10650659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
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32
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Abstract
Sixty-eight patients underwent radial recession osteotomy for avascular necrosis of the lunate were retrospectively evaluated after an average follow-up period of 52 months. Twenty-five patients had undergone 1 or more additional procedures concurrently for treatment of Kienböck's disease. Pain diminished in 93% of patients, grip strength improved, and wrist motion was preserved; 75% of patients continued in their original occupations, including heavy labor. Surgical complications were uncommon. Four patients subsequently underwent salvage procedures, including 2 total wrist arthrodeses. Three of these 4 patients were receiving workers' compensation. One third of patients demonstrated lunate healing after joint leveling. Preliminary results suggest that concomitant lunate revascularization or vascularized bone grafting may improve the radiographic result. With rare exceptions, radial recession osteotomy relieves pain and improves function in Kienböck's disease.
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Affiliation(s)
- D E Quenzer
- Department of Orthopedics, Mayo Clinic, Rochester, MN 55905, USA
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Abstract
Trispiral tomography enhances the staging of Kienböck's disease and aids in surgical planning. The clinical records, plain x-rays, and trispiral tomograms of 105 patients with Kienböck's disease were reviewed. When tomograms were used, upward revision of the classification stage was indicated in 73% of patients with stage I or stage II disease and in 10% of those with stage III disease. On tomograms, 91% of patients had lunate fractures, compared with 55% on plain films. The most common lunate fracture seen on trispiral tomograms was a transverse shear fracture that represented lunate collapse; the next most common was a midcoronal fracture that may be displaced, causing fragment extrusion palmarly or dorsally. The most common instability pattern was nondissociative proximal row flexion, seen in stage III. Indices of carpal collapse and ulnar translation may be useful in following up patients, but values vary widely among patients.
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Affiliation(s)
- D E Quenzer
- Department of Orthopedics, Mayo Clinic, Rochester, MN 55905, USA
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34
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Abstract
Sixty-six surface replacement proximal interphalangeal prostheses with a CrCo proximal and an ultrahigh-molecular-weight polyethylene distal component were used in the hands of 47 patients (mean age, 58 years) over a 14-year period. There were 37 fingers with degenerative arthrosis, 16 with traumatic arthrosis, and 13 with rheumatoid arthritis. The mean follow-up period was 4.5 years (range, 1-14 years). The results based on pain relief, motion, and deformity were good in 32 fingers, fair in 19, and poor in 15. Poor results occurred primarily in fingers with previous extensive injury or static deformity. Results with a dorsal approach were better than those with a lateral or palmar approach. Component loosening at the bone-cement junction beyond a minimal radiolucent line was seen in one late x-ray. Results in individuals changed little after the first year of follow-up care, but results overall improved during the course of the study, perhaps because of improvements in surgical technique and experience.
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Affiliation(s)
- R L Linscheid
- Department of Orthopedics, Mayo Clinic, Rochester, MN 55905, USA
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35
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Concha M, Vidal MA, Figueroa CD, Caorsi I. Cellular and subcellular distribution of 2,4-dinitrophenyl groups in mouse epidermis and regional lymph nodes after epicutaneous application of 2,4-dinitrofluorobenzene. Arch Dermatol Res 1991; 283:251-7. [PMID: 1718226 DOI: 10.1007/bf01106111] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The cellular and subcellular distribution of 2,4-dinitrophenyl (DNP) groups in the epidermis and regional lymph nodes of the mouse was investigated after epicutaneous application of 2,4-dinitrofluorobenzene (DNFB) to sensitized and non-sensitized mice. The peroxidase-antiperoxidase method and the immunogold technique were used to visualize the DNP groups at both light and electron microscopic levels. The highest intensity of immunolabelling was found on tonofilaments of keratinocytes present in the upper layers of the epidermis. On the other hand, in vitro experiments showed that DNFB has the capacity to bind keratin which, together with immunocytochemistry, suggests that this molecule may be one of the skin protein carriers for DNFB. In addition, intense immunostaining for DNP was observed in the Golgi area of some epidermal Langerhans cells. Cells immunoreactive to DNP were also observed in the marginal sinus of cervical lymph nodes 6, 12 and 24 h after challenge. Immunoelectron microscopy revealed immunoreactive DNP groups in phagosomes of Langerhans cells at this site. The present findings support the hypothesis that the hapten DNFB penetrates passively into the cytoplasm of Langerhans cells, concentrates in the Golgi area and, during the migration of Langerhans cells to the lymph nodes, it is probably processed in the lysosomes before its presentation to T lymphocytes.
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Affiliation(s)
- M Concha
- Instituto de Histologia y Patologia, Facultad de Medicina, Universidad Austral de Chile, Casilla, Valdivia
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Abstract
Nine patients with the diagnosis of unilateral Preiser's disease were seen between 1970 and 1987. The mean age of four male and five female patients was 37 years (range, 20 to 70 years). The diagnosis was based on radiographic evidence of sclerosis, fragmentation, erosion, and collapse of the proximal pole of the scaphoid. Onset was usually insidious but two had a preexisting radial hypoplasia, a third had a modest scaphoid malunion, and a fourth had a recent fall. Treatment consisted of scaphoid excision and silicone rubber prosthetic replacement in three, debridement of necrotic bone fragments in one, and different periods of cast support and observation in the remaining five. No relationship to ulnar variance was seen. Mean follow-up was 6.9 years. Of the scaphoid implants, two had subluxated, but only one was painful. In the more conservatively treated group, pain and function were only modestly limiting in four, who returned to their original occupations as did the one treated by curettage of necrotic bone in the proximal pole. One patient (case 4) was severely incapacitated because of associated severe congenital anomalies of the lower extremities. Polyaxial tomography permitted a better assessment of the degree of involvement and carpal alignment. Preiser's disease is a rare affliction of the carpal scaphoid which may involve the entire bone in avascular changes but primarily leads to fragmentation and collapse of the proximal pole. A conservative approach to treatment is favored based on this experience.
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Affiliation(s)
- M A Vidal
- Servei de Cirurgia Orthopedica, Hospital Crey Roja, Barcelona, Spain
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37
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Menezes MN, Garcia-Zapata MT, Soares VA, Vidal MA, Lima JC, Marsden PD. The interpretation of faecal streaks produced by different instars of triatomine bugs. Trans R Soc Trop Med Hyg 1990; 84:799. [PMID: 2128981 DOI: 10.1016/0035-9203(90)90086-t] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- M N Menezes
- Núcleo de Medicina Tropical, Universidade de Brasília, Brazil
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Abstract
A single base-pair mutation (beta s) in codon 6 of the human beta-globin gene, causing a single amino-acid substitution, is the cause of sickle cell anaemia. The mutant haemoglobin molecule, HbS, polymerizes when deoxygenated and causes deformation of the erythrocytes to a characteristic 'sickled' shape. Sickling of cells in small vessels causes painful crises and other life-threatening complications. Although the molecular basis for sickle cell anaemia has been known for 30 years, no definitive treatment is available. An animal model of sickle cell anaemia would not only allow a detailed analysis of the factors that initiate erythrocyte sickling in vivo and of the pathophysiology of the disease, but would also permit the development of novel approaches to the treatment of the disease. By using the dominant control region sequences from the human beta-globin locus, together with human alpha- and beta s-globin genes, we have obtained three transgenic mice with HbS levels ranging from 10 to 80% of total haemoglobin in their red cells. As observed in homozygous and heterozygous Hbs patients, the erythrocytes of this mouse sickle readily on deoxygenation. Irreversibly sickled cells, which are characteristic of sickle-cell patients homozygous for beta s, are also observed in the peripheral blood of the mouse with high levels of HbS.
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Affiliation(s)
- D R Greaves
- Laboratory of Gene Structure and Expression, National Institute for Medical Research, The Ridgeway, Mill Hill, London, UK
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Eccles SJ, Vidal MA, Wrighton CJ, Grosveld FG, Burke JF. Rapid detection of ultraviolet-induced reversion of an amber mutation in mouse L cells. Proc Natl Acad Sci U S A 1989; 86:1297-301. [PMID: 2919178 PMCID: PMC286675 DOI: 10.1073/pnas.86.4.1297] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
An amber codon (TAG) was introduced into the N-terminal coding region of the murine H-2Kb gene. The mutant gene was transfected into mouse L cells, and a clone containing a single unrearranged chromosomally integrated copy of the mutant gene was mutagenized with 254-nm UV radiation. Surviving cells were scored for surface expression of H-2Kb protein with in situ immunoperoxidase staining. Revertants were detected at a frequency of 3 X 10(-6) at a dose of 40 J/m2 (3-5% survival). Revertant genes, cloned by plasmid rescue, contained the expected thymine-to-cytosine transitions at the amber codon. These data show that revertants can be rapidly detected in mammalian cells without selection and provide a basis for the development of mammalian cell lines that could be used to study mutational phenomena. During this study the steady-state level of mRNA was reduced in L cells carrying the amber mutant H-2Kb gene compared with L cells containing a wild-type or revertant H-2Kb gene. This reduction was shown not to be due to transcriptional differences, suggesting that the amber mutation decreases stability of the H-2Kb mRNA.
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Affiliation(s)
- S J Eccles
- Medical Research Council Collaborative Center, London, United Kingdom
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40
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Cristoffanini AP, Vidal MA, Cea X, Zapata C. [Multiple myeloma. Clinical experience of 15 years in the 10th region]. Rev Med Chil 1987; 115:1061-5. [PMID: 3506266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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41
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Vidal MA, Conde FP. Alternative mechanism of protein A-immunoglobulin interaction the VH-associated reactivity of a monoclonal human IgM. J Immunol 1985; 135:1232-8. [PMID: 3925002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The immunoglobulin site(s) that mediates the alternative mechanism of interaction between immunoglobulins and staphylococcal protein A (SpA) was studied by using a monoclonal human IgM. Several IgM fragments were tested for their inhibitory effect in a competitive binding assay of 125I-IgM to SpA. Only those fragments containing Fab mu pieces showed some inhibitory activity. The reactivity of the Fab mu region was retained in some of its subfragments, such as Fv or the VH domain, unlike isolated light chains or VL domains. Furthermore, antibodies specific for the VH domain completely inhibited the SpA-IgM interaction. These results indicate that the alternative SpA-binding site of IgM is located in VH regions.
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42
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Vidal MA, Conde FP. Alternative mechanism of protein A-immunoglobulin interaction the VH-associated reactivity of a monoclonal human IgM. The Journal of Immunology 1985. [DOI: 10.4049/jimmunol.135.2.1232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
The immunoglobulin site(s) that mediates the alternative mechanism of interaction between immunoglobulins and staphylococcal protein A (SpA) was studied by using a monoclonal human IgM. Several IgM fragments were tested for their inhibitory effect in a competitive binding assay of 125I-IgM to SpA. Only those fragments containing Fab mu pieces showed some inhibitory activity. The reactivity of the Fab mu region was retained in some of its subfragments, such as Fv or the VH domain, unlike isolated light chains or VL domains. Furthermore, antibodies specific for the VH domain completely inhibited the SpA-IgM interaction. These results indicate that the alternative SpA-binding site of IgM is located in VH regions.
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Abstract
The protein A-binding site of human IgM was studied by affinity chromatography on SpA-Sepharose using fragments derived from a human monoclonal SpA-reactive IgM, Iz. Neither Fabmu nor (Fc) 5mu fragments were retained on the column but IgM reactivity was unaffected by thermic treatment during proteolysis. Products intermediate between IgM and (Fc) 5mu fragments produced during shorter proteolysis showed a reactivity related to their content in Fabmu regions. On the other hand mild reduction of IgM Iz to monomeric subunits results in a dramatic loss of SpA-affinity. However these subunits, like F(ab') 2mu but unlike Fab'mu fragments, showed a significant interaction with the column. Thus, the principal requirement for SpA reactivity with IgM Iz seems to be related to the presence of Fabmu regions in a polymeric state resembling native IgM.
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Vidal MA, Conde FP. Interaction between staphylococcal protein A and human immunoglobulin M takes place through the F(ab')2 gamma-receptor on the protein A molecule. Immunol Lett 1982; 5:75-8. [PMID: 6218075 DOI: 10.1016/0165-2478(82)90036-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Abstract
Human immunoglobulin M binds to protein A-bearing Staphylococcus aureus. This binding is specific for protein A since it is inhibited by rabbit Fab against Staphylococcal protein A. Analysis of the IgM binding data gives an apparent KD of 0.94 nM and a maximum capacity of approximately 2 X 10(3) binding sites of IgM per bacteria.
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Pintor-Toro JA, Sanchez-Madrid F, Vidal MA, Conde P. Studies on the modification of Escherichia coli ribosomal protein L7/L12 by succinic anhydride. Experientia 1982; 38:241-3. [PMID: 6174364 DOI: 10.1007/bf01945089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Lysine modification by increasing quantities of succinic anhydride in the Escherichia coli ribosomal protein L7/L12 produces loss of its ability in reconstitution of elongation-factor-G-dependent GTP hydrolysis and polyphenylalanine synthesis activities, showing lower antigenicity and loss of antigenic determinants.
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Abstract
A method is described for preparing IgM from normal serum in two chromatographic steps. A gel filtration column gives a macroglobulin peak containing the IgM, purified by affinity chromatography on protein A--Sepharose. Immunoglobulin recovery is around 50%.
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Abstract
The IgG fraction obtained from pooled human plasma by eluting a protein A column with a buffer at pH 2.5 was contaminated with approximately 30% of the IgM originally present in the sample. Both the IgM and the IgA contamination can be reduced and the IgG recovery maintained at 90% of the bound IgG when elution of the column is performed at pH 4.0
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DeFeudis FV, Orensanz Muñoz LM, Vidal MA, Corrochano G, Sanchez del Alamo M. High-affinity binding of beta-alanine to cerebral synaptosomes might involve glycine-receptors. Experientia 1978; 34:1169-70. [PMID: 102523 DOI: 10.1007/bf01922937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
High-affinity, Na+-independent binding of beta-alanine to a synaptosomal fraction of rat brain was potently inhibited by glycine and by some other alpha-amino acids, but not by taurine or GABA. This binding mechanism, which was also sensitive to both bicuculline and strychnine, might involve synaptic receptors for both beta-alanine and glycine.
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DeFeudis FV, Orensanz Munoz LM, Vidal MA, Corrochano G, Sanchez del Alamo MS. Substrate-specificity of "high-affinity", Na+ -independent binding of beta-alanine to cerebral synaptosomal-mitochondrial fractions. Gen Pharmacol 1978; 9:341-5. [PMID: 29823 DOI: 10.1016/0306-3623(78)90073-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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