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1.
Environ Toxicol Chem ; 43(6): 1442-1457, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38695731

RESUMO

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.


Assuntos
Celulose , Monitoramento Ambiental , Cadeia Alimentar , Microplásticos , Spheniscidae , Poluentes Químicos da Água , Animais , Microplásticos/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Equador , Zooplâncton/efeitos dos fármacos , Água do Mar/química
2.
Medicine (Baltimore) ; 102(46): e35841, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37986377

RESUMO

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.


Assuntos
Doenças Transmissíveis , Transplante de Rim , Humanos , Tacrolimo/efeitos adversos , Ácido Micofenólico/efeitos adversos , Imunossupressores/efeitos adversos , Transplante de Rim/efeitos adversos , México/epidemiologia , Estudos Prospectivos , Quimioterapia Combinada , Doenças Transmissíveis/etiologia , Hospitais , Rejeição de Enxerto/prevenção & controle , Rejeição de Enxerto/epidemiologia , Sobrevivência de Enxerto
3.
Sci Total Environ ; 881: 163372, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37054791

RESUMO

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 %.


Assuntos
Cacau , Poluentes do Solo , Cádmio/análise , Solo/química , Peru , Cacau/química , Poluentes do Solo/análise
4.
Rev. biol. trop ; 71abr. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1449488

RESUMO

Introducción: Los arrecifes de coral son ecosistemas altamente degradados, por lo que ha sido necesario implementar acciones de restauración activa para recuperar su estructura y funcionamiento. Se ha implementado la propagación clonal para obtener fragmentos pequeños (~ 10 cm) de las ramas distales de colonias donadoras de corales de la especie Acropora palmata, para posteriormente fijarlos en el sustrato arrecifal, simulando el efecto de dispersión que ocurre de manera natural en esta especie, a lo que en este trabajo se denomina ''dispersión asistida". Sin embargo, es necesario evaluar los efectos de esta técnica como son: la cantidad de fragmentos que se puede obtener de cada colonia, el periodo de recuperación de tejido de las colonias donadoras y los fragmentos sembrados. Objetivo: Evaluar el efecto de poda en las colonias donadoras estimando el porcentaje de tejido podado de colonias donadoras de A. palmata y su tasa de recuperación 30 meses después. Métodos: Se realizaron cuatro monitoreos: antes, inmediatamente después de la poda, un mes después de la siembra, y 30 meses después, en cuatro colonias de A. palmata localizadas en el Parque Nacional Costa Occidental de Isla Mujeres, Punta Cancún y Punta Nizuc en el Caribe mexicano. La modelación 3D basada en fotogrametría se realizó con el software Agisoft Metashape Pro, mientras que las métricas de área de superficie de tejido, extensión radial y apical se obtuvieron mediante el software CloudCompare. Resultados: Posterior a la colecta de fragmentos de las colonias, se observó que el material utilizado en la dispersión asistida representa menos del 12% del tejido vivo. Después de un mes, las colonias donadoras presentaban una recuperación del 5% con tejido nuevo recubriendo las áreas de corte. Las colonias donadoras perdieron, en promedio, 65% de tejido vivo tras el impacto de cuatro huracanes, y en un caso la colonia fue totalmente eliminada, pero con los fragmentos sembrados se pudo conservar el genotipo. Conclusiones: La dispersión asistida podría incrementar el tejido vivo de corales ramificados en intervalos de tiempo relativamente cortos, sin comprometer la integridad de la colonia donadora, si se poda menos del 12%.


Introduction: Coral reefs are highly degraded ecosystems, for which it has been necessary to implement active restoration actions to recover their structure and functioning. Asexual propagation has been implemented to obtain small fragments (~10 cm) from the distal branches of donor colonies of corals of the species Acropora palmata, to subsequently relocate them in the reef substrate, simulating the dispersion effect that occurs naturally in the species, which in this work is called assisted propagation. However, it is necessary to evaluate the effects of this technique, such as the number of fragments that can be obtained from each colony, the tissue recovery period of the donor colonies and fragments. Objective: To address the effect of pruning on donor colonies by estimating the percentage of live tissue removed from donor colonies of A. palmata and their recovery rate after 30-months. Methods: Four surveys were carried out: before, immediately after pruning, one month after outplanting, and 30 months after pruning on four colonies of A. palmata located in the Parque Nacional Costa Occidental de Isla Mujeres, Punta Cancún and Punta Nizuc in the Mexican Caribbean. Photogrammetry-based 3D modeling was performed using Agisoft Metashape Pro software, while tissue surface area, radial and apical growth were obtained using CloudCompare software. Results: After fragment collection, the material used in the assisted propagation represents less than 12% of the living tissue. After one month, the donor colonies showed a recovery of 5%, with new tissue covering the cut areas. The donor colonies lost on average 65 % of living tissue after four hurricanes, and in one case the colony was lost all together, but with the outplanted fragments the genotype could be preserved. Conclusions: Assisted propagation could increase living tissue of branching corals in relatively short intervals of time, without serious damage to the donor colony if less than 12 % is removed.

5.
Integr Environ Assess Manag ; 19(4): 870-895, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35893578

RESUMO

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.


Assuntos
Poluentes Ambientais , Caça , Mudança Climática , Equador , Efeitos Antropogênicos , Ecossistema
6.
Mar Environ Res ; 180: 105696, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35932509

RESUMO

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.


Assuntos
Mudança Climática , Tubarões , Animais , Biodiversidade , Chile , Ecossistema , Tubarões/fisiologia
7.
PLoS One ; 17(6): e0268736, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35687546

RESUMO

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.


Assuntos
Tubarões , Animais , Aves , Isótopos de Carbono , Ecologia/métodos , Ecossistema , Feminino , Isótopos de Nitrogênio/análise
8.
Neotrop. ichthyol ; 20(3): e210160, 2022. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1406129

RESUMO

For 175 years, an unremarkable bass, the Grape-eye Seabass (Hemilutjanus macrophthalmos), has been known from coastal waters in the Eastern Pacific. To date, its phylogenetic placement and classification have been ignored. A preliminary osteological examination of Hemilutjanus hinted that it may have affinities with the Acropomatiformes. To test this hypothesis, we conducted a phylogenetic analysis using UCE and Sanger sequence data to study the placement of Hemilutjanus and the limits and relationships of the Acropomatiformes. We show that Hemilutjanus is a malakichthyid, and our results corroborate earlier studies that have resolved a polyphyletic Polyprionidae; accordingly, we describe Stereolepididae, new family, for Stereolepis. With these revisions, the Acropomatiformes is now composed of the: Acropomatidae; Banjosidae; Bathyclupeidae; Champsodontidae; Creediidae; Dinolestidae; Epigonidae; Glaucosomatidae; Hemerocoetidae; Howellidae; Lateolabracidae; Malakichthyidae; Ostracoberycidae; Pempheridae; Pentacerotidae; Polyprionidae; Scombropidae; Stereolepididae, new family; Symphysanodontidae; Synagropidae; and Schuettea. Finally, using our new hypothesis, we demonstrate that acropomatiforms repeatedly evolved bioluminescence and transitioned between shallow waters and the deep sea.


Durante más de 175 años el Serranido ojo de uva (Hemilutjanus macrophthalmos), un pez parecido a la lubina común, se conoce de las zonas costeras del Pacífico Oriental. Al día de hoy la posición filogenética de esta especie se desconoce. Un estudio preliminar de Hemilutjanus basado en caracteres osteológicos sugirió que esta especie puede tener afinidades con el orden Acropomatiformes. Para investigar la posición filogenética de Hemilutjanus y los límites y relaciones dentro del orden Acropomatiformes realizamos análisis filogenéticos utilizando datos de secuencias Sanger y de UCEs. Demostramos que Hemilutjanus es un malakichthyid y nuestros resultados recobran Polyprionidae como una familia polifilética corroboran así estudios anteriores. En consecuencia, diagnosticamos y describimos una nueva familia de peces, Stereolepididae, que incluye ambas especies del genero Stereolepis. Con esta revisión, ahora el orden Acropomatiformes se compone de las familias: Acropomatidae; Banjosidae; Bathyclupeidae; Champsodontidae; Creediidae; Dinolestidae; Epigonidae; Glaucosomatidae; Hemerocoetidae; Howellidae; Lateolabracidae; Malakichthyidae; Ostracoberycidae; Pempheridae; Pentacerotidae; Polyprionidae; Scombropidae; Stereolepididae, nueva familia; Symphysanodontidae; Synagropidae; y Schuettea. Finalmente, utilizando nuestra hipótesis filogenética, demostramos que bioluminiscencia ha evolucionado varias veces dentro de los miembros de Acropomatiformes y tambien demostramos múltiples transiciones entre aguas someras y zonas profundas del océano dentro de este grupo.


Assuntos
Animais , Filogenia , Especificidade da Espécie , Bass/anatomia & histologia , Perciformes/anatomia & histologia , Oceano Pacífico
9.
Sci Rep ; 11(1): 14959, 2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34294756

RESUMO

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.


Assuntos
Código de Barras de DNA Taxonômico/métodos , Tubarões/anatomia & histologia , Tubarões/crescimento & desenvolvimento , Animais , Tamanho Corporal , Conservação dos Recursos Naturais , Pesqueiros , Oceano Pacífico , Comportamento Sexual Animal , Tubarões/classificação , Tubarões/genética
10.
Sci Rep ; 11(1): 8785, 2021 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-33888850

RESUMO

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.

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