Tolerance to hypometabolism and arousal induced by hibernation in the apple snail Pomacea canaliculata (Caenogastropoda, Ampullariidae)

Pomacea canaliculata may serve as a model organism for comparative studies of oxidative damage and antioxidant defenses in active, hibernating and arousing snails. Oxidative damage (as TBARS), free radical scavenging capacity (as ABTS+ oxidation), uric acid (UA) and glutathione (GSH) concentrations, activities of superoxide dismutase (SOD) and catalase (CAT), and the protein expression levels of heat shock proteins (Hsp70, Hsc70, Hsp90) were studied in digestive gland, kidney and foot. Tissue TBARS of hibernating snails (45days) was higher than active snails. Hibernation produced an increase of ABTS+ in digestive gland, probably because of the sustained antioxidant defenses (UA and/or GSH and SOD levels). Kidney protection during the activity-hibernation cycle seemed provided by increased UA concentrations. TBARS in the foot remained high 30min after arousal with no changes in ABTS+, but this tissue increased ABTS+ oxidation at 24h to expenses increased UA and decreased GSH levels, and with no changes in SOD and CAT activities. The level of Hsp70 in kidney showed no changes throughout the activity-hibernation cycle but it increased in the foot after hibernation. The tissue levels of Hsp90 in snails hibernating were higher than active snails and returned to baseline 24h after arousal. Results showed that chronic cooling produces a significant oxidative damage in three studied tissues and that these tissue damages are overcome quickly (between 30min to 24h) with fluctuations in different antioxidant defenses (UA, GSH, CAT) and heat shock proteins (Hsp70 and Hsp90).Fil: Giraud Billoud, Maximiliano German. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Castro Vazquez, Alfredo Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Campoy Díaz, Alejandra Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Giuffrida, Pablo M.. Universidad Nacional de Cuyo; ArgentinaFil: Vega, Israel Aníbal. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; Argentin

Twenty years of the ‘Preparation for Oxidative Stress’ (POS) theory: Ecophysiological advantages and molecular strategies

Freezing, dehydration, salinity variations, hypoxia or anoxia are some of the environmental constraints that many organisms must frequently endure. Organisms adapted to these stressors often reduce their metabolic rates to maximize their chances of survival. However, upon recovery of environmental conditions and basal metabolic rates, cells are affected by an oxidative burst that, if uncontrolled, leads to (oxidative) cell damage and eventually death. Thus, a number of adapted organisms are able to increase their antioxidant defenses during an environmental/functional hypoxic transgression; a strategy that was interpreted in the 1990s as a “preparation for oxidative stress” (POS). Since that time, POS mechanisms have been identified in at least 83 animal species representing different phyla including Cnidaria, Nematoda, Annelida, Tardigrada, Echinodermata, Arthropoda, Mollusca and Chordata. Coinciding with the 20th anniversary of the postulation of the POS hypothesis, we compiled this review where we analyze a selection of examples of species showing POS-mechanisms and review the most recent advances in understanding the underlying molecular mechanisms behind those strategies that allow animals to survive in harsh environments

Insights from an Integrated View of the Biology of Apple Snails (Caenogastropoda: Ampullariidae)

Submitted by sandra infurna ([email protected]) on 2016-02-16T12:59:35Z No. of bitstreams: 1 silvana_thiengo_etal_IOC_2015.pdf: 1030588 bytes, checksum: 1feaf6021ccd94c9bf314dbc7b49ccc8 (MD5)Approved for entry into archive by sandra infurna ([email protected]) on 2016-02-16T13:49:31Z (GMT) No. of bitstreams: 1 silvana_thiengo_etal_IOC_2015.pdf: 1030588 bytes, checksum: 1feaf6021ccd94c9bf314dbc7b49ccc8 (MD5)Made available in DSpace on 2016-02-16T13:49:31Z (GMT). No. of bitstreams: 1 silvana_thiengo_etal_IOC_2015.pdf: 1030588 bytes, checksum: 1feaf6021ccd94c9bf314dbc7b49ccc8 (MD5) Previous issue date: 2015Howard University. Department of Biology. Washington, DC, USA / University of Hawaii. Pacific Biosciences Research Center. Honolulu, Hawaii, USA /Smithsonian Institution. National Museum of Natural History. Washington, DC, USA.Southwestern University. Department of Biology. Georgetown, Texas, USA.Instituto de Fisiología (FCM-UNCuyo). Laboratorio de Fisiología (IHEM-CONICET). Mendoza, Argentina.University of West Florida. Department of Biology. Pensacola, Florida, USA.Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP, CONICET). La Plata, Argentina.Universidad Nacional del Sur-CONICET. Laboratorio de Ecología, INBIOSUR. Bahia Blanca, Argentina.Hong Kong Baptist University. Department of Biology. Kowloon, Hong Kong.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Malacologia. Rio de Janeiro, RJ, Brasil.Instituto de Fisiología (FCM-UNCuyo). Laboratorio de Fisiología (IHEM-CONICET). Mendoza, Argentina / Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales. Área de Biologia. Mendoza, Argentina.NARO Kyushu Okinawa Agricultural Research Center. Kumamoto, Japan.Nara Women’s University. Faculty of Science. Kitauoya-nishi, Nara, Japan.Universidad Nacional del Sur-CONICET. Laboratorio de Ecología, INBIOSUR. Bahia Blanca, Argentina.Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP, CONICET). La Plata, Argentina.Instituto de Fisiología (FCM-UNCuyo). Laboratorio de Fisiología (IHEM-CONICET). Mendoza, Argentina / Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales. Área de Biologia. Mendoza, Argentina.Instituto de Fisiología (FCM-UNCuyo). Laboratorio de Fisiología (IHEM-CONICET). Mendoza, Argentina / Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales. Área de Biologia. Mendoza, Argentina.Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP, CONICET). La Plata, Argentina / Comisión de Investigaciones Científicas (CIC). La Plata, Argentina.Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP, CONICET). La Plata, Argentina.Instituto de Fisiología (FCM-UNCuyo). Laboratorio de Fisiología (IHEM-CONICET). Mendoza, Argentina / Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales. Área de Biologia. Mendoza, Argentina.Instituto de Fisiología (FCM-UNCuyo). Laboratorio de Fisiología (IHEM-CONICET). Mendoza, Argentina / Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales. Área de Biologia. Mendoza, Argentina.Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP, CONICET). La Plata, Argentina.Instituto de Fisiología (FCM-UNCuyo). Laboratorio de Fisiología (IHEM-CONICET). Mendoza, Argentina / Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales. Área de Biologia. Mendoza, Argentina.University of Hawaii. Pacific Biosciences Research Center. Honolulu, Hawaii, USA / NARO Kyushu Okinawa Agricultural Research Center. Koshi, Kumamoto, Japan.Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP, CONICET). La Plata, Argentina.Instituto de Fisiología (FCM-UNCuyo). Laboratorio de Fisiología (IHEM-CONICET). Mendoza, Argentina.Universidad Nacional del Sur-CONICET. Laboratorio de Ecología, INBIOSUR. Bahia Blanca, Argentina.Universidad Nacional del Sur-CONICET. Laboratorio de Ecología, INBIOSUR. Bahia Blanca, Argentina.Smithsonian Institution. National Museum of Natural History. Washington, DC, USA..Hong Kong Baptist University. Department of Biology. Kowloon, Hong Kong.Universidad Nacional del Sur-CONICET. Laboratorio de Ecología, INBIOSUR. Bahia Blanca, Argentina.Universidad Nacional del Sur-CONICET. Laboratorio de Ecología, INBIOSUR. Bahia Blanca, Argentina.Florida Institute of Technology. Biological Sciences Department. Melbourne, Florida, USA.The Pomacea Project, Inc., Pensacola, Florida, USA.University of Hawaii. Pacific Biosciences Research Center. Honolulu, Hawaii, USA.Apple snails (Ampullariidae) are among the largest and most ecologically important freshwater snails. The introduction of multiple species has reinvigorated the field and spurred a burgeoning body of research since the early 1990s, particularly regarding two species introduced to Asian wetlands and elsewhere, where they have become serious agricultural pests. This review places these recent advances in the context of previous work, across diverse fields ranging from phylogenetics and biogeography through ecology and developmental biology, and the more applied areas of environmental health and human disease. The review does not deal with the role of ampullariids as pests, nor their control and management, as this has been substantially reviewed elsewhere. Despite this large and diverse body of research, significant gaps in knowledge of these important snails remain, particularly in a comparative framework. The great majority of the work to date concerns a single species, Pomacea canaliculata, which we see as having the potential to become a model organism in a wide range of fields. However, additional comparative data are essential for understanding this diverse and potentially informative group. With the rapid advances in genomic technologies, many questions, seemingly intractable two decades ago, can be addressed, and ampullariids will provide valuable insights to our understanding across diverse fields in integrative biology

Search for direct top squark pair production in final states with two leptons in s=13\sqrt{s} = 13 TeV pppp collisions with the ATLAS detector

International audienceThe results of a search for direct pair production of top squarks in events with two opposite-charge leptons (electrons or muons) are reported, using $36.1~\hbox {fb}^{-1}$ of integrated luminosity from proton–proton collisions at $\sqrt{s}=13$ TeV collected by the ATLAS detector at the Large Hadron Collider. To cover a range of mass differences between the top squark $\tilde{t}$ and lighter supersymmetric particles, four possible decay modes of the top squark are targeted with dedicated selections: the decay $\tilde{t} \rightarrow b \tilde{\chi }_{1}^{\pm }$ into a b-quark and the lightest chargino with $\tilde{\chi }_{1}^{\pm } \rightarrow W \tilde{\chi }_{1}^{0}$ , the decay $\tilde{t} \rightarrow t \tilde{\chi }_{1}^{0}$ into an on-shell top quark and the lightest neutralino, the three-body decay $\tilde{t} \rightarrow b W \tilde{\chi }_{1}^{0}$ and the four-body decay $\tilde{t} \rightarrow b \ell \nu \tilde{\chi }_{1}^{0}$ . No significant excess of events is observed above the Standard Model background for any selection, and limits on top squarks are set as a function of the $\tilde{t}$ and $\tilde{\chi }_{1}^{0}$ masses. The results exclude at 95% confidence level $\tilde{t}$ masses up to about 720 GeV, extending the exclusion region of supersymmetric parameter space covered by previous searches

Searches for the ZγZ\gamma decay mode of the Higgs boson and for new high-mass resonances in pppp collisions at s=13\sqrt{s} = 13 TeV with the ATLAS detector

International audienceThis article presents searches for the Zγ decay of the Higgs boson and for narrow high-mass resonances decaying to Zγ, exploiting Z boson decays to pairs of electrons or muons. The data analysis uses 36.1 fb$^{−1}$ of pp collisions at $\sqrt{s}=13$ recorded by the ATLAS detector at the CERN Large Hadron Collider. The data are found to be consistent with the expected Standard Model background. The observed (expected — assuming Standard Model pp → H → Zγ production and decay) upper limit on the production cross section times the branching ratio for pp → H → Zγ is 6.6. (5.2) times the Standard Model prediction at the 95% confidence level for a Higgs boson mass of 125.09 GeV. In addition, upper limits are set on the production cross section times the branching ratio as a function of the mass of a narrow resonance between 250 GeV and 2.4 TeV, assuming spin-0 resonances produced via gluon-gluon fusion, and spin-2 resonances produced via gluon-gluon or quark-antiquark initial states. For high-mass spin-0 resonances, the observed (expected) limits vary between 88 fb (61 fb) and 2.8 fb (2.7 fb) for the mass range from 250 GeV to 2.4 TeV at the 95% confidence level