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1.
Proc Natl Acad Sci U S A ; 119(20): e2117440119, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35533277

RESUMEN

Marine traffic is increasing globally yet collisions with endangered megafauna such as whales, sea turtles, and planktivorous sharks go largely undetected or unreported. Collisions leading to mortality can have population-level consequences for endangered species. Hence, identifying simultaneous space use of megafauna and shipping throughout ranges may reveal as-yet-unknown spatial targets requiring conservation. However, global studies tracking megafauna and shipping occurrences are lacking. Here we combine satellite-tracked movements of the whale shark, Rhincodon typus, and vessel activity to show that 92% of sharks' horizontal space use and nearly 50% of vertical space use overlap with persistent large vessel (>300 gross tons) traffic. Collision-risk estimates correlated with reported whale shark mortality from ship strikes, indicating higher mortality in areas with greatest overlap. Hotspots of potential collision risk were evident in all major oceans, predominantly from overlap with cargo and tanker vessels, and were concentrated in gulf regions, where dense traffic co-occurred with seasonal shark movements. Nearly a third of whale shark hotspots overlapped with the highest collision-risk areas, with the last known locations of tracked sharks coinciding with busier shipping routes more often than expected. Depth-recording tags provided evidence for sinking, likely dead, whale sharks, suggesting substantial "cryptic" lethal ship strikes are possible, which could explain why whale shark population declines continue despite international protection and low fishing-induced mortality. Mitigation measures to reduce ship-strike risk should be considered to conserve this species and other ocean giants that are likely experiencing similar impacts from growing global vessel traffic.


Asunto(s)
Tiburones , Animales , Especies en Peligro de Extinción , Plancton , Navíos
2.
Mol Phylogenet Evol ; 166: 107316, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34537324

RESUMEN

Marine species that are widely distributed in the Tropical Eastern Pacific (TEP) has served as a model for studying biogeographic patterns resulting from the effects of intraregional habitat discontinuities and oceanographic processes on the diversification and evolution of cryptobenthic reef fishes. Tomicodon petersii, a clingfish (Gobiesocidae) endemic to the TEP, is found on very shallow rocky reefs from central Mexico to northern Peru, and in the Cocos and Galapagos islands. We evaluated the effect of likely biogeographic barriers in different parts of the TEP on the diversification process of this species. We used one mitochondrial and three nuclear DNA markers from 112 individuals collected across the distribution range of T. petersii. Our phylogenetic results showed the samples constituted a monophyletic group, with three well-supported, allopatric subgroups: in the Mexican province, the Panamic province (from El Salvador to Ecuador), and the Galapagos Islands. The split between the Mexican and more southerly clades was estimated to occur at the end of the Miocene ca. 5.74 Mya, and the subsequent cladogenetic event separating the Galapagos population from the Panamic population at the junction of the Pliocene and Pleistocene, ca. 2.85 Mya. The species tree, Bayesian species delimitation tests (BPP), STACEY, and substantial genetic distances separating these three populations indicate that these three independent evolutionary units likely include two unnamed species. The cladogenetic events that promoted the formation of those genetically differentiated groups are consistent with disruptive effects on gene flow of habitat discontinuities and oceanographic processes along the mainland shoreline in the TEP and of ocean-island isolation, in conjunction with the species intrinsic life-history characteristics.


Asunto(s)
Peces , Especiación Genética , Animales , Teorema de Bayes , ADN Mitocondrial/genética , Ecosistema , Peces/genética , Filogenia
3.
Mol Phylogenet Evol ; 173: 107496, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35569809

RESUMEN

The Panamic Clingfish Gobiesox adustus is widely distributed in the Tropical Eastern Pacific (TEP), from the central Gulf of California, Mexico to Ecuador, including the oceanic Revillagigedo Archipelago, and Isla del Coco. This cryptobenthic species is restricted to very shallow rocky-reef habitats. Here, we used one mitochondrial and three nuclear DNA markers from 155 individuals collected across the distribution range of the species in order to evaluate if geographically structured populations exist and to elucidate its evolutionary history. Phylogenetic analyses recovered a monophyletic group, with four well-supported, allopatric subgroups. Each subgroup corresponded to one of the following well-known biogeographic regions/provinces: 1) the Revillagigedo Archipelago, 2) the Cortez + Mexican provinces (Mexico), 3) the Panamic province (from El Salvador to Ecuador), and 4) Isla del Coco. A molecular-clock analysis showed a mean date for the divergence between clade I (the Revillagigedos and Cortez + Mexican provinces) and clade II (Panamic province and Isla del Coco) in the Pliocene, at ca. 5.33 Mya. Within clade I, the segregation between the Revillagigedos and Cortez + Mexican province populations was dated at ca. 1.18 Mya, during the Pleistocene. Within clade II, the segregation between samples of Isla del Coco and the Panamic province samples was dated at ca. 0.77 Mya, during the Pleistocene. The species tree, Bayesian species delimitation tests (BPP and STACEY), the ΦST, AMOVA, and the substantial genetic distances that exist between those four subgroups, indicate that they are independent evolutionary units. These cladogenetic events seem to be related to habitat discontinuities, and oceanographic and geological processes that produce barriers to gene flow for G. adustus, effects of which are enhanced by the intrinsic ecological characteristics of this species.


Asunto(s)
Evolución Biológica , Peces , Animales , Teorema de Bayes , ADN Mitocondrial/genética , Peces/genética , Humanos , Filogenia , Filogeografía
5.
Aten Primaria ; 52(10): 680-689, 2020 12.
Artículo en Español | MEDLINE | ID: mdl-32381266

RESUMEN

OBJECTIVE: To determine the association between family typology and dysfunction in families with adolescents in a Mexican population. DESIGN: Cross-sectional observational study. SETTING AND POPULATION: A total of 437 families in a Mexican population with adolescents attending a public high school. MAIN MEASUREMENTS: Determination of family typology (Mexican Family Medicine Council and Consensus) and family function (family APGAR) in adolescents and their parents/guardians. Identification of families with concordant perceptions among members (Cohen kappa), in which the association between typology and perception of family dysfunction was determined (odds ratio [OR]). RESULTS: The types of families are associated with family function by kinship, physical presence in the home and the level of family poverty. From the perception of the adolescent, the types are associated with: simple nuclear (OR 0.5, 95% CI 0.3-0.8), extended single parent (OR 1.9, 95% CI 1.03-3.5), integrated nucleus (OR 0.6, 95% CI 0.4-0.9), low family poverty (OR 0.5, 95% CI 0.3-0.8), and high family poverty (OR 5.3, 95% CI 1.5-18.6). From the perception of the tutor: the single parent (OR 1.9, 95% CI 1.09-3.4), and high family poverty (OR 2.9, 95% CI 1.1-7.7). There were 259 families with concordant perception of family function/dysfunction with a κ=0.189, determining that the types associated are: simple nuclear (OR 0.4, 95% CI 0.2-0.7), single-parent (OR 1.7, 95% CI 0.80-3.8), integrated nucleus (OR 0.5, 95% CI 0.3-0.8), non-integrated nucleus (OR 1.9, 95% CI 1.09-3.5), and high family poverty (OR 13.8, 95% CI 1.7-108.5). CONCLUSION: The family types with adolescents associated with family dysfunction are single-parent families with a non-integrated nucleus and high family poverty, and as protective factors, the simple nuclear and integrated nucleus.


Asunto(s)
Padres , Pobreza , Adolescente , Estudios Transversales , Familia , Humanos , Oportunidad Relativa , Instituciones Académicas
6.
Mol Phylogenet Evol ; 132: 232-242, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30550965

RESUMEN

We examined the role of geographic barriers and historical processes on the diversification of Apogon species within the tropical eastern Pacific (TEP). Mitochondrial and nuclear DNA sequences were used in Bayesian and Maximum likelihood analyses to generate a phylogenetic hypothesis for Apogon species. Bayesian inferences were used to date the cladogenetic events. Analyses with BioGeoBEARS were conducted to reconstruct the biogeographic history and ancestral ranges. The phylogenetic results show a monophyletic clade of TEP Apogon species with A. imberbis from the eastern Atlantic as sister species. The two lineages diverged during the Miocene. Within the TEP clade, two subclades diverged at around 11.1 million years ago (Mya): one clusters the coastal continental species (A. pacificus, A. retrosella and A. dovii), and the second clusters the oceanic island species (A. atradorsatus, A. atricaudus and A. guadalupensis). The estimated diversification times of these subclades were 9.8 and 7.1 Mya, respectively. Within each subclade, species divergences occurred during the Pliocene-Pleistocene epochs. The divergent event between the Atlantic A. imberbis and Apogon TEP clade corresponds to the first closure event of the Central American Seaway. The biogeographic history of Apogon within the TEP appears to be the result of vicariant, dispersal and founder events that occurred during the last 11 million years. The vicariant and dispersal events occurred along the mainland and were associated with the origin of the Central American Gap. The founder events could have allowed the invasion of Apogon to TEP island areas and could have been driven by ancient warming oceanic waters, changes in circulation of marine currents, and the presence of seamounts in ancient marine ridges that allowed the settlement of marine biota. These factors may have allowed Apogon lineages to cross the TEP biogeographic barriers at different times, with subsequent genetic isolation.


Asunto(s)
Perciformes/clasificación , Animales , Teorema de Bayes , Citocromos b/clasificación , Citocromos b/genética , Evolución Molecular , Especiación Genética , Proteínas de Homeodominio/clasificación , Proteínas de Homeodominio/genética , Filogenia , Rodopsina/clasificación , Rodopsina/genética , Análisis de Secuencia de ADN
7.
Vascular ; 26(5): 483-489, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29498327

RESUMEN

Objective Inferior vena cava occlusion is a potentially life-threatening complication related to caval filters. We present our experience with filter-induced inferior vena cava occlusion in order to assess the feasibility, safety, and effectiveness of endovascular management. Methods A retrospective review of all patients undergoing inferior vena cava filter placement over a 60-month study period was performed. From this cohort, a total of 10 cases of inferior vena cava occlusion after filter placement were identified. Demographics, clinical data, procedures, and outcomes were extracted. Patients were followed to the last clinic visit or until they died. Results One-hundred eighty filters were placed by our group practice during the study period. Of those, a total of 10 patients were identified. Overall, there were 7 males; the mean age was 57.1 years (25-78 years). The median time between inferior vena cava filter placement and filter occlusion was 105 days (range 5-4745 days). All patients were clinically symptomatic at the time of their presentation. Nine out of 10 patients were successfully managed endovascularly. Trellis™-8 thrombectomy was the most common endovascular strategy performed ( n = 9). Four patients had balloon angioplasty, two of those with stent placement for chronically occluded inferior vena cava/iliac veins. No thromboembolic complications developed during a median follow-up period of 233 days (range 4-1083 days). Conclusions Endovascular management of inferior vena cava occlusion is feasible, safe, and effective in decreasing thrombus burden in the presence of an inferior vena cava filter. Further studies evaluating long-term inferior vena cava patency and optimal surveillance regimen after endovascular management of filter-related inferior vena cava occlusion are warranted.


Asunto(s)
Angioplastia de Balón , Procedimientos Endovasculares/métodos , Implantación de Prótesis/instrumentación , Filtros de Vena Cava , Vena Cava Inferior/cirugía , Trombosis de la Vena/terapia , Adulto , Anciano , Angioplastia de Balón/instrumentación , Arizona , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/instrumentación , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Flebografía , Implantación de Prótesis/efectos adversos , Estudios Retrospectivos , Stents , Trombectomía/efectos adversos , Factores de Tiempo , Resultado del Tratamiento , Vena Cava Inferior/diagnóstico por imagen , Trombosis de la Vena/diagnóstico por imagen , Trombosis de la Vena/etiología
8.
J Endovasc Ther ; 22(1): 99-104, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25775688

RESUMEN

PURPOSE: To evaluate the performance and safety of the Trellis-8 system, a pharmacomechanical thrombolysis infusion catheter, and adjunctive therapies in the treatment of symptomatic inferior vena cava (IVC) filter-related acute thrombotic occlusion. METHODS: Eight consecutive patients (6 men; mean age 57.4 years, range 34-78 years) with acute thrombotic occlusion of the IVC in the presence of an IVC filter underwent percutaneous venous thrombectomy using the Trellis-8 thrombectomy system and adjunctive techniques between January 2009 and November 2013. Demographics, clinical data, procedures, and outcomes were retrospectively reviewed. All patients had clinical signs of lower extremity venous hypertension on presentation. The median time between IVC filter placement and occlusion was 25 months. Patients were followed for the development of thromboembolic complications to the last clinic visit or until they died. RESULTS: The procedure was technically successful in 6 patients, whereas it could not be performed in 2 due to failure to cross the occlusion. The median follow-up period was 7.8 months, at which time all patients undergoing successful Trellis-8 thrombectomy had relief of symptoms without thromboembolic or bleeding complications. CONCLUSION: In this limited performance and safety evaluation, the Trellis-8 thrombectomy system combined with adjunctive therapies, such as mechanical thrombectomy and balloon angioplasty, was effective in 75% of patients with IVC filter-related acute caval occlusion.


Asunto(s)
Fibrinolíticos/administración & dosificación , Trombolisis Mecánica , Terapia Trombolítica , Filtros de Vena Cava/efectos adversos , Vena Cava Inferior , Trombosis de la Vena/etiología , Trombosis de la Vena/terapia , Enfermedad Aguda , Adulto , Anciano , Angioplastia de Balón/métodos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Terapia Trombolítica/métodos , Resultado del Tratamiento , Trombosis de la Vena/diagnóstico
9.
Environ Toxicol Chem ; 43(6): 1442-1457, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38695731

RESUMEN

Microplastic pollution threatens some of the world's most iconic locations for marine biodiversity, including the remote Galápagos Islands, Ecuador. Using the Galápagos penguin (Spheniscus mendiculus) as a sentinel species, the present study assessed microplastics and suspected anthropogenic cellulose concentrations in surface seawater and zooplankton near Santa Cruz and Galápagos penguin colonies (Floreana, Isabela, Santiago), as well as in penguin potential prey (anchovies, mullets, milkfish) and penguin scat. On average, 0.40 ± 0.32 microplastics L-1 were found in surface seawater (<10 µm; n = 63 L), while 0.003, 0.27, and 5.12 microplastics individual-1 were found in zooplankton (n = 3372), anchovies (n = 11), and mullets (n = 6), respectively. The highest concentration (27 microplastics individual-1) was observed in a single milkfish. Calculations based on microplastics per gram of prey, in a potential diet composition scenario, suggest that the Galápagos penguin may consume 2881 to 9602 microplastics daily from prey. Despite this, no microplastics or cellulose were identified in 3.40 g of guano collected from two penguins. Our study confirms microplastic exposure in the pelagic food web and endangered penguin species within the UNESCO World Heritage site Galápagos Islands, which can be used to inform regional and international policies to mitigate plastic pollution and conserve biodiversity in the global ocean. Environ Toxicol Chem 2024;43:1442-1457. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Asunto(s)
Celulosa , Monitoreo del Ambiente , Cadena Alimentaria , Microplásticos , Spheniscidae , Contaminantes Químicos del Agua , Animales , Microplásticos/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad , Ecuador , Zooplancton/efectos de los fármacos , Agua de Mar/química
10.
Sci Total Environ ; 881: 163372, 2023 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37054791

RESUMEN

Peru is the eighth largest producer of cacao beans globally, but high cadmium contents are constraining access to international markets which have set upper thresholds for permitted concentrations in chocolate and derivatives. Preliminary data have suggested that high cadmium concentrations in cacao beans are restricted to specific regions in the country, but to date no reliable maps exist of expected cadmium concentrations in soils and cacao beans. Drawing on >2000 representative samples of cacao beans and soils we developed multiple national and regional random forest models to develop predictive maps of cadmium in soil and cacao beans across the area suitable for cacao cultivation. Our model projections show that elevated concentrations of cadmium in cacao soils and beans are largely restricted to the northern parts of the country in the departments of Tumbes, Piura, Amazonas and Loreto, as well as some very localized pockets in the central departments of Huánuco and San Martin. Unsurprisingly, soil cadmium was the by far most important predictor of bean cadmium. Aside from the south-eastern to north-western spatial trend of increasing cadmium values in soils and beans, the most important predictors of both variables in nation-wide models were geology, rainfall seasonality, soil pH and rainfall. At regional level, alluvial deposits and mining operations were also associated with higher cadmium levels in cacao beans. Based on our predictive map of cadmium in cacao beans we estimate that while at a national level <20 % of cacao farming households might be impacted by the cadmium regulations, in the most affected department of Piura this could be as high as 89 %.


Asunto(s)
Cacao , Contaminantes del Suelo , Cadmio/análisis , Suelo/química , Perú , Cacao/química , Contaminantes del Suelo/análisis
11.
Integr Environ Assess Manag ; 19(4): 870-895, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35893578

RESUMEN

For decades, multiple anthropogenic stressors have threatened the Galápagos Islands. Widespread marine pollution such as oil spills, persistent organic pollutants, metals, and ocean plastic pollution has been linked to concerning changes in the ecophysiology and health of Galápagos species. Simultaneously, illegal, unreported, and unregulated fishing are reshaping the composition and structure of endemic and native Galápagos pelagic communities. In this novel review, we discuss the impact of anthropogenic pollutants and their associated ecotoxicological implications for Galápagos species in the face of climate change stressors. We emphasize the importance of considering fishing pressure and marine pollution, in combination with climate-change impacts, when assessing the evolutionary fitness of species inhabiting the Galápagos. For example, the survival of endemic marine iguanas has been negatively affected by organic hydrocarbons introduced via oil spills, and endangered Galápagos sea lions exhibit detectable concentrations of DDT, triggering potential feminization effects and compromising the species' survival. During periods of ocean warming (El Niño events) when endemic species undergo nutritional stress, climate change may increase the vulnerability of these species to the impacts of pollutants, resulting in the species reaching its population tipping point. Marine plastics are emerging as a deleterious and widespread threat to endemic species. The Galápagos is treasured for its historical significance and its unparalleled living laboratory and display of evolutionary processes; however, this unique and iconic paradise will remain in jeopardy until multidisciplinary and comprehensive preventative management plans are put in place to mitigate and eliminate the effects of anthropogenic stressors facing the islands today. We present a critical analysis and synthesis of anthropogenic stressors with some progress from local and international institutional efforts and call to action more precautionary measures along with new management philosophies focused on understanding the processes of change through research to champion the conservation of the Galápagos. Integr Environ Assess Manag 2023;19:870-895. © 2022 SETAC.


Asunto(s)
Contaminantes Ambientales , Caza , Cambio Climático , Ecuador , Efectos Antropogénicos , Ecosistema
12.
Medicine (Baltimore) ; 102(46): e35841, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37986377

RESUMEN

Evidence supporting a starting dose of 2 g/day of mycophenolate mofetil (MMF) in combination with tacrolimus (TAC) for renal transplantation (RT) is still limited, but maintaining a dose of <2 g could result in worse clinical outcomes in terms of acute rejection (AR). This study aimed to determine the association between AR and infectious and noninfectious complications after RT with a dose of 1.5 g vs 2 g of MMF. A prospective cohort study was performed with a 12-month follow-up of recipients of RT from living donors with low (1.5 g/day) or standard (2 g/day) doses of MMF. The association between adverse effects and complications and doses of MMF was examined using Cox proportional hazard models, and survival free of AR, infectious diseases, and noninfectious complications was evaluated using the Kaplan-Meier test. At the end of the follow-up, the incidence of infectious diseases was 52% versus 50% (P = .71) and AR was 5% versus 5% (P = .86), respectively. The survival rate free of gastrointestinal (GI) complications requiring medical attention was higher in the low-dose group than in the standard-dose dose (88% vs 45%, respectively; P < .001). The use of 1.5 g/day of MMF confers a reduction in GI complications without an increase in infectious diseases or the risk of AR.


Asunto(s)
Enfermedades Transmisibles , Trasplante de Riñón , Humanos , Tacrolimus/efectos adversos , Ácido Micofenólico/efectos adversos , Inmunosupresores/efectos adversos , Trasplante de Riñón/efectos adversos , México/epidemiología , Estudios Prospectivos , Quimioterapia Combinada , Enfermedades Transmisibles/etiología , Hospitales , Rechazo de Injerto/prevención & control , Rechazo de Injerto/epidemiología , Supervivencia de Injerto
13.
J Phys Chem A ; 116(49): 12136-47, 2012 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-23140309

RESUMEN

The energy-dependent branching ratios of the complementary fragment ions [C(5)H(5)O](+) and [HC(6)H(4)NH](+) ([M - C(5)H(5)O](+)), originating from the N-(2-furylmethyl)aniline molecular ion, [HC(6)H(4)NH-C(5)H(5)O](+•), were obtained from Rice-Ramsperger-Kassel-Marcus (RRKM) rate calculations based on density functional theory (DFT) energy profiles. The UB3LYP/6-311G+(3df,2p)//UB3LYP/6-31G(d) level of theory was used to model the competitive reaction mechanisms by which the molecular ion can be fragmented. Initially, eight pairs of products were taken into account, corresponding to the combination of two isomeric structures for each fragment ion and the concomitant radicals, which can be formed by direct dissociations or through some isomerization-fragmentation pathways. A great deal of the obtained pathways was discarded by looking over the kinetic barrier heights and the individual RRKM rate coefficients calculated for all the steps. This way, the potential energy profiles were simplified to only three reaction channels, two pathways to [C(5)H(5)O](+) and one to [M - C(5)H(5)O](+). The pre-equilibrium and steady-state approximations were then applied to different regions of the remaining potential energy profiles, allowing the branching ratios of the complementary fragment ions to be easily calculated and discriminated among the three rival processes. According to these results, the major fragment ion in the ion source is [C(5)H(5)O](+), which is produced as a mixture of two structures, the furfuryl and pyrylium cations, one formed by a direct C-N bond cleavage and the other through an isomerization-fragmentation channel. In turn, the direct fragmentation is the only mechanism to produce [M - C(5)H(5)O](+). To confront these results with the available experimental information, the model was broadened out to the 4-substituted analogues [4-R-C(6)H(4)NH-C(5)H(5)O](+•) in which R = F, Br, Cl, CH(3), and OCH(3), finding excellent correlations of the calculated branching ratios and the relative abundances in the electron ionization mass spectra.


Asunto(s)
Compuestos de Anilina/química , Furanos/química , Teoría Cuántica , Iones/química , Estructura Molecular , Espectrometría de Masa por Ionización de Electrospray
14.
PLoS One ; 17(6): e0268736, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35687546

RESUMEN

Changes in life-history requirements drive trophic variations, particularly in large marine predators. The life history of many shark species is still poorly known and understanding their dietary ontogeny is a challenging task, especially for highly migratory species. Stable isotope analysis has proven as a useful method for examining the foraging strategies of sharks and other marine predators. We assessed the foraging strategies and ontogenetic changes of scalloped hammerhead sharks, Sphyrna lewini, at Galapagos Marine Reserve (GMR), by analysing δ13C and δ15N signatures in different maturity stages. Our isotopic results suggest ontogenetic shifts in resource use between sub-adult and adult stages, but not between adult and juvenile stages. Carbon isotopic signatures found in the juvenile stage were enriched in contrast to sub-adults (~0.73‰) suggesting a combination of the maternal input and the use of coastal resources around the Galapagos Islands. Adult female sharks also showed enrichment in δ13C (~0.53‰) in comparison to sub-adult stages that suggest feeding in high primary productivity areas, such as the GMR. This study improves the understanding of the trophic ecology and ontogenetic changes of a highly migratory shark that moves across the protected and unprotected waters of the Eastern Tropical Pacific.


Asunto(s)
Tiburones , Animales , Aves , Isótopos de Carbono , Ecología/métodos , Ecosistema , Femenino , Isótopos de Nitrógeno/análisis
15.
Mar Environ Res ; 180: 105696, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35932509

RESUMEN

Variability and climate change due to anthropic influence have brought about alterations to marine ecosystems, that, in turn, have affected the physiology and metabolism of ectotherm species, such as the common hammerhead shark (Sphyrna lewini). However, the impact that climate variability may have on this species' distribution, particularly in the Eastern Tropical Pacific Marine Corridor, which is considered an area with great marine biodiversity, is unknown. The purpose of this research was to evaluate the effect of derivate impact of climate change on the oceanographic distribution of the hammerhead shark (Sphyrna lewini) in the Eastern Tropical Pacific Marine Corridor, contrasting the present and future scenarios for 2050. The methodology used was an ecological niche model based on the KUENM R package software that uses the maximum entropy algorithm (MaxEnt). The modelling was made for the year 2050 under RCP2.6 and RCP8.5 scenarios. A total of 952 models were made, out of which only one met the statistical parameters established as optimal, for future scenarios. The environmental suitability for S.lewini shows that this species would migrate to the south in the Chilean Pacific, associated with a possible warming that the equatorial zone will have and the possible cooling that the subtropical zone of the South Pacific will have by 2050, the product of changes in oceanographic dynamics.


Asunto(s)
Cambio Climático , Tiburones , Animales , Biodiversidad , Chile , Ecosistema , Tiburones/fisiología
16.
Ecol Evol ; 11(14): 9206-9216, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34306617

RESUMEN

For predators, cooperation can decrease the cost of hunting and potentially augment the benefits. It can also make prey accessible that a single predator could not catch. The degree of cooperation varies substantially and may range from common attraction to a productive food source to true cooperation involving communication and complementary action by the individuals involved. We here describe cooperative hunting of Galapagos sea lions (Zalophus wollebaeki) for Amberstripe scad (Decapterus muroadsi), a schooling, fast swimming semipelagic fish. A group of 6-10 sea lions, usually females only, drove scad over at least 600-800 m from open water into a cove where, in successful hunts, they drove them ashore. Frequently, these "core hunters" were joined toward the final stages of the hunt by another set of opportunistic sea lions from a local colony at that beach. The "core hunters" did not belong to that colony and apparently were together coming toward the area specifically for the scad hunt. Based on the observation of 40 such hunts from 2016 to 2020, it became evident that the females performed complementary actions in driving the scad toward the cove. No specialization of roles in the hunt was observed. All "core hunters" and also opportunistically joining sea lions from the cove shared the scad by randomly picking up a few of the 25-300 (mean 100) stranded fish as did scrounging brown pelicans. In one of these hunts, four individual sea lions were observed to consume 7-8 fish each in 25 s. We conclude that the core hunters must communicate about a goal that is not present to achieve joint hunting but presently cannot say how they do so. This is a surprising achievement for a species that usually hunts singly and in which joint hunting plays no known role in the evolution of its sociality.

17.
Sci Rep ; 11(1): 8785, 2021 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-33888850

RESUMEN

Currently, the Galapagos sea lion (GSL, Zalophus wollebaeki) and Galapagos fur seal (GFS, Arctocephalus galapagoensis) are among the most important endemic species for conservation in the Galapagos Archipelago. Both are classified as "Endangered" since their populations have undergone drastic declines over the last several decades. In this study we estimated the abundance of both otariids, and their population trends based using counts conducted between 2014 and 2018 in all their rookeries, and we analyzed the influence of environmental variability on pup production. The GSL population size in 2018 in the archipelago was estimated to be between 17,000 to 24,000 individuals and has increased at an average annual rate of 1% over the last five years after applying correction factors. The highest number of GSL counted in the archipelago was in 2014 followed by a population decline of 23.8% in 2015 that was associated with the El Niño event that occurred during that year. Following this event, the population increased mainly in the northern, central and southeastern rookeries. The GSL pup abundance showed a decreasing trend with the increase in intensity of the El Niño. The GFS population in 2018 was counted in 3,093 individuals and has increased at an annual rate of 3% from 2014 to 2018. A high number of GFS counted in 2014 was followed by a population decrease of 38% in 2015, mainly in the western rookeries. There was interannual population fluctuations and different growth trends among regions of the archipelago. GSL and GFS pup abundance has a strong decreasing tendency with the increase in the subthermocline temperature (ST) and the El Niño 1 + 2 index. Our results provide evidence that both species are highly vulnerable to periodic oceanographic-atmospheric events in the Galapagos Archipelago which impact prey abundance and the flow of energy in the unique Galapagos ecosystem.

18.
J Wildl Dis ; 57(3): 623-627, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-33787897

RESUMEN

During the 2018 breeding season, an outbreak of respiratory disease occurred among Galapagos sea lions (Zalophus wollebaeki) that inhabit rookeries near urban areas with introduced fauna such as dogs and cats. Several sea lions had nasal discharge and respiratory distress and were in poor body condition. Eighteen sea lions were captured for a general health assessment including collection of blood for serology and nasal discharge for culture and PCR. Samples were analyzed for 15 respiratory pathogens known to infect cats, dogs, and marine mammals. There was no evidence for interspecies pathogen transmission between Galapagos sea lions and domestic animals. Several bacterial pathogens associated with respiratory tract infection in the California sea lion (Zalophus californianus) were isolated. Mycoplasma spp. were identified by PCR in nasal discharge samples but were not the species commonly found in cats and dogs.


Asunto(s)
Enfermedades de los Gatos , Enfermedades de los Perros , Mycoplasma , Leones Marinos , Animales , Gatos , Perros
19.
Sci Rep ; 11(1): 14959, 2021 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-34294756

RESUMEN

Shark fishing, driven by the fin trade, is the primary cause of global shark population declines. Here, we present a case study that exemplifies how industrial fisheries are likely depleting shark populations in the Eastern Tropical Pacific Ocean. In August 2017, the vessel Fu Yuan Yu Leng 999, of Chinese flag, was detained while crossing through the Galápagos Marine Reserve without authorization. This vessel contained 7639 sharks, representing one of the largest seizures recorded to date. Based on a sample of 929 individuals (12%), we found 12 shark species: 9 considered as Vulnerable or higher risk by the IUCN and 8 listed in CITES. Four species showed a higher proportion of immature than mature individuals, whereas size-distribution hints that at least some of the fishing ships associated with the operation may have been using purse-seine gear fishing equipment, which, for some species, goes against international conventions. Our data expose the magnitude of the threat that fishing industries and illegal trade represent to sharks in the Eastern Tropical Pacific Ocean.


Asunto(s)
Código de Barras del ADN Taxonómico/métodos , Tiburones/anatomía & histología , Tiburones/crecimiento & desarrollo , Animales , Tamaño Corporal , Conservación de los Recursos Naturales , Explotaciones Pesqueras , Océano Pacífico , Conducta Sexual Animal , Tiburones/clasificación , Tiburones/genética
20.
Int J Infect Dis ; 107: 18-24, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33862205

RESUMEN

BACKGROUND: In our population, anti-thymocyte globulin (ATG) of 1 mg/Kg/day for 4 days is used; which permits not using valgancyclovir (VGC) prophylaxis in some renal transplant recipients (RTR) with moderate risk (R+), to reduce costs. This study aimed to determine the incidence and risk of developing cytomegalovirus (CMV), with or without prophylaxis, when exposed to low doses of ATG or basiliximab (BSL). PATIENTS AND METHODS: A retrospective cohort included 265 RTR with follow-up of 12 months. Prophylaxis was used in R-/D+ and some R+. Tacrolimus (TAC), mycophenolate mofetil, and prednisone were used in all patients. Logistic regression analysis was performed to estimate the risk of CMV in RTR with or without VGC. RESULTS: Cytomegalovirus was documented in 46 (17.3%) patients: 20 (43.5%) with CMV infection, and 26 (56.5%) with CMV disease. Anti-thymocyte globulin was used in 39 patients (85%): 32 R+, six D+/R-, and one D-/R-. ATG was used in 90% (27 of 30) of patients with CMV and without prophylaxis. The multivariate analysis showed an association of risk for CMV with the absence of prophylaxis (RR 2.29; 95% CI 1.08-4.86), ATG use (RR 3.7; 95% CI 1.50-9.13), TAC toxicity (RR 3.77; 95% CI 1.41-10.13), and lymphocytes at the sixth post-transplant month (RR 1.77; 95% CI 1.0-3.16). CONCLUSIONS: Low doses of ATG favored the development of CMV and a lower survival free of CMV compared with BSL. In scenarios where resources for employing VGC are limited, BSL could be an acceptable strategy.


Asunto(s)
Suero Antilinfocítico/uso terapéutico , Basiliximab/uso terapéutico , Infecciones por Citomegalovirus/epidemiología , Citomegalovirus/aislamiento & purificación , Trasplante de Riñón/efectos adversos , Valganciclovir/uso terapéutico , Adulto , Antivirales/uso terapéutico , Femenino , Ganciclovir/uso terapéutico , Humanos , Terapia de Inmunosupresión/métodos , Inmunosupresores/uso terapéutico , Donadores Vivos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Ácido Micofenólico/uso terapéutico , Estudios Retrospectivos , Factores de Riesgo , Tacrolimus/uso terapéutico , Receptores de Trasplantes
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