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1.
Bioinformatics ; 39(5)2023 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-37137232

RESUMEN

MOTIVATION: We present pyGOMoDo, a Python library to perform homology modeling and docking, specifically designed for human GPCRs. pyGOMoDo is a python wrap-up of the updated functionalities of GOMoDo web server (https://molsim.sci.univr.it/gomodo). It was developed having in mind its usage through Jupyter notebooks, where users can create their own protocols of modeling and docking of GPCRs. In this article, we focus on the internal structure and general capabilities of pyGOMoDO and on how it can be useful for carrying out structural biology studies of GPCRs. RESULTS: The source code is freely available at https://github.com/rribeiro-sci/pygomodo under the Apache 2.0 license. Tutorial notebooks containing minimal working examples can be found at https://github.com/rribeiro-sci/pygomodo/tree/main/examples.


Asunto(s)
Biología Computacional , Programas Informáticos , Humanos , Biología Computacional/métodos , Simulación de Dinámica Molecular , Biblioteca de Genes
2.
Int J Mol Sci ; 25(18)2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39337439

RESUMEN

Metal-organic frameworks (MOFs) are promising materials for processes such as carbon dioxide (CO2) capture or its storage. In this work, the adsorption of CO2 and nitrogen (N2) in Co3(ndc)3(dabco) MOF (ndc: 2,6-naphthalenedicarboxylate; dabco: 1,4-diazabicyclo[2.2.2]octane) is reported for the first time over the temperature range of 273-323 K and up to 35 bar. The adsorption isotherms are successfully described using the Langmuir isotherm model. The heats of adsorption for CO2 and N2, determined through the Clausius-Clapeyron equation, are 20-27 kJ/mol and 10-11 kJ/mol, respectively. The impact of using pressure and/or temperature swings on the CO2 working capacity is evaluated. If a flue gas with 15% CO2 is fed at 6 bar and 303 K and regenerated at 1 bar and 373 K, 1.58 moles of CO2 can be captured per kg of MOF. The analysis of the multicomponent adsorption of typical flue gas streams (15% CO2 balanced with N2), using the ideal adsorbed solution theory (IAST), shows that at 1 bar and 303 K, the CO2/N2 selectivity is 11.5. In summary, this work reports essential data for the design of adsorption-based processes for CO2 capture using a Co3(ndc)3(dabco) MOF, such as pressure swing adsorption (PSA).


Asunto(s)
Dióxido de Carbono , Estructuras Metalorgánicas , Nitrógeno , Dióxido de Carbono/química , Nitrógeno/química , Estructuras Metalorgánicas/química , Adsorción , Temperatura , Cobalto/química
3.
Med Lav ; 115(3): e2024021, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38922838

RESUMEN

Contact dermatitis is a common cutaneous inflammatory condition, triggered by exposure to irritant substances or allergens. Nickel is the most prevalent allergen, a metal widely used in accessories, furniture, office materials, food and in industry, with multiple exposure pathways, making it difficult to assess which exposure is causing allergic dermatitis. Here, we report a case of an administrative worker with chronic hand eczema, limited to the radial metacarpophalangeal region of the left hand, caused by occupational exposure to nickel, confirmed by nickel deposition test on the hand and a positive test with a metallic stapler used at her workplace.


Asunto(s)
Dermatitis Alérgica por Contacto , Dermatitis Profesional , Níquel , Femenino , Humanos , Dermatitis Alérgica por Contacto/etiología , Dermatitis Alérgica por Contacto/diagnóstico , Dermatitis Profesional/etiología , Dermatitis Profesional/diagnóstico , Dermatosis de la Mano/inducido químicamente , Dermatosis de la Mano/etiología , Níquel/efectos adversos , Exposición Profesional/efectos adversos
4.
Mol Psychiatry ; 27(2): 907-917, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34980886

RESUMEN

Various single nucleotide polymorphisms (SNPs) in the oxytocin receptor (OXTR) gene have been associated with behavioral traits, autism spectrum disorder (ASD) and other diseases. The non-synonymous SNP rs4686302 results in the OXTR variant A218T and has been linked to core characteristics of ASD, trait empathy and preterm birth. However, the molecular and intracellular mechanisms underlying those associations are still elusive. Here, we uncovered the molecular and intracellular consequences of this mutation that may affect the psychological or behavioral outcome of oxytocin (OXT)-treatment regimens in clinical studies, and provide a mechanistic explanation for an altered receptor function. We created two monoclonal HEK293 cell lines, stably expressing either the wild-type or A218T OXTR. We detected an increased OXTR protein stability, accompanied by a shift in Ca2+ dynamics and reduced MAPK pathway activation in the A218T cells. Combined whole-genome and RNA sequencing analyses in OXT-treated cells revealed 7823 differentially regulated genes in A218T compared to wild-type cells, including 429 genes being associated with ASD. Furthermore, computational modeling provided a molecular basis for the observed change in OXTR stability suggesting that the OXTR mutation affects downstream events by altering receptor activation and signaling, in agreement with our in vitro results. In summary, our study provides the cellular mechanism that links the OXTR rs4686302 SNP with genetic dysregulations associated with aspects of ASD.


Asunto(s)
Trastorno del Espectro Autista , Nacimiento Prematuro , Trastorno del Espectro Autista/tratamiento farmacológico , Femenino , Células HEK293 , Humanos , Recién Nacido , Oxitocina/metabolismo , Embarazo , Nacimiento Prematuro/tratamiento farmacológico , Receptores de Oxitocina/genética , Receptores de Oxitocina/metabolismo , Relación Estructura-Actividad
5.
Surg Endosc ; 37(3): 1617-1628, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36693918

RESUMEN

BACKGROUND: Sleeve gastrectomy (SG) is the most common metabolic and bariatric surgical (MBS) procedure worldwide. Despite the desired effect of SG on weight loss and remission of obesity-associated medical problems, there are some concerns regarding the need to do revisional/conversional surgeries after SG. This study aims to make an algorithmic clinical approach based on an expert-modified Delphi consensus regarding redo-surgeries after SG, to give bariatric and metabolic surgeons a guideline that might help for the best clinical decision. METHODS: Forty-six recognized bariatric and metabolic surgeons from 25 different countries participated in this Delphi consensus study in two rounds to develop a consensus on redo-surgeries after SG. An agreement/disagreement ≥ 70.0% on statements was considered to indicate a consensus. RESULTS: Consensus was reached for 62 of 72 statements and experts did not achieve consensus on 10 statements after two rounds of online voting. Most of the experts believed that multi-disciplinary team evaluation should be done in all redo-procedures after SG and there should be at least 12 months of medical and supportive management before performing redo-surgeries after SG for insufficient weight loss, weight regain, and gastroesophageal reflux disease (GERD). Also, experts agreed that in case of symptomatic GERD in the presence of adequate weight loss, medical treatment for at least 1 to 2 years is an acceptable option and agreed that Roux-en Y gastric bypass is an appropriate option in this situation. There was disagreement consensus on efficacy of omentopexy in rotation and efficacy of fundoplication in the presence of a dilated fundus and GERD. CONCLUSION: Redo-surgeries after SG is still an important issue among bariatric and metabolic surgeons. The proper time and procedure selection for redo-surgery need careful considerations. Although multi-disciplinary team evaluation plays a key role to evaluate best options in these situations, an algorithmic clinical approach based on the expert's consensus as a guideline can help for the best clinical decision-making.


Asunto(s)
Derivación Gástrica , Reflujo Gastroesofágico , Obesidad Mórbida , Humanos , Técnica Delphi , Reoperación/métodos , Derivación Gástrica/métodos , Gastrectomía/métodos , Reflujo Gastroesofágico/etiología , Reflujo Gastroesofágico/cirugía , Pérdida de Peso , Obesidad Mórbida/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
6.
J Environ Manage ; 308: 114622, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35124314

RESUMEN

Plastic derived carbon nanotubes (CNTs) were tested as catalysts in persulfate activation for the first time. Four catalysts were prepared by wetness impregnation and co-precipitation (using Al2O3, Ni, Fe and/or Al) and implemented to grow CNTs by chemical vapour deposition (CVD) using low-density polyethylene (LDPE) as carbon feedstock. A catalyst screening was performed in batch mode and the best performing CNTs (CNT@Ni+Fe/Al2O3-cp) led to a high venlafaxine mass removal rate (3.17 mg g-1 h-1) in ultrapure water after 90 min (even with a mixture of micropollutants). Its degradation increased when the matrix was replaced by drinking water and negligibly affected in surface water. A composite polymeric membrane was then fabricated with CNT@Ni+Fe/Al2O3-cp and polyvinylidene fluoride (PVDF), a high venlafaxine mass removal rate in surface water being also observed in 24 h of continuous operation. Therefore, the results herein reported open a window of opportunity for the valorisation of plastic wastes in this catalytic application performed in continuous mode.


Asunto(s)
Nanotubos de Carbono , Contaminantes Químicos del Agua , Catálisis , Polietileno , Agua , Contaminantes Químicos del Agua/análisis
7.
Ann Surg ; 273(1): 57-65, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33332873

RESUMEN

OBJECTIVE: The aim of this study was to investigate the approach (open or laparoscopic) and mesh type (synthetic or biological) in ventral hernias in a clean setting.Summary of Background Data: The level of evidence on the optimal surgical approach and type of mesh in ventral hernia repair is still low. METHODS: Patients with a ventral abdominal hernia (diameter 4-10 cm) were included in this double-blind randomized controlled trial across 17 hospitals in 10 European countries. According to a 2 × 2-factorial design, patients were allocated to 4 arms (open retromuscular or laparoscopic intraperitoneal, with synthetic or Surgisis Gold biological mesh). Patients and outcome assessors were blinded to mesh type used. Major postoperative complication rate (hernia recurrence, mesh infection, or reoperation) within 3 years after surgery, was the primary endpoint in the intention-to-treat population. RESULTS: Between September 1st, 2005, and August 7th, 2009, 253 patients were randomized and 13 excluded. Six of 61 patients (9.8%) in the open synthetic mesh arm, 15 of 66 patients (22.7%) in the open biological mesh arm, 7 of 64 patients (10.9%) in the laparoscopic synthetic mesh arm and 17 of 62 patients (27.4%) in the laparoscopic biological mesh arm had a major complication. The use of biological mesh resulted in significantly more complications (P = 0.013), also after adjusting for hernia type, body mass index, and study site. The trial was prematurely stopped due to an unacceptable high recurrence rate in the biological mesh arms. CONCLUSIONS: The use of Surgisis Gold biological mesh is not recommended for noncomplex ventral hernia repair. TRIAL REGISTRATION: This trial was registered at controlled-trials.com (ISRCTN34532248).


Asunto(s)
Bioprótesis , Hernia Ventral/cirugía , Herniorrafia/métodos , Laparoscopía , Mallas Quirúrgicas , Adulto , Anciano , Método Doble Ciego , Europa (Continente) , Femenino , Humanos , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Resultado del Tratamiento
8.
Int J Mol Sci ; 22(4)2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33546429

RESUMEN

Inside hippocampal circuits, neuroplasticity events that individual cells may undergo during synaptic transmissions occur in the form of Long-Term Potentiation (LTP) and Long-Term Depression (LTD). The high density of NMDA receptors expressed on the surface of the dendritic CA1 spines confers to hippocampal CA3-CA1 synapses the ability to easily undergo NMDA-mediated LTP and LTD, which is essential for some forms of explicit learning in mammals. Providing a comprehensive kinetic model that can be used for running computer simulations of the synaptic transmission process is currently a major challenge. Here, we propose a compartmentalized kinetic model for CA3-CA1 synaptic transmission. Our major goal was to tune our model in order to predict the functional impact caused by disease associated variants of NMDA receptors related to severe cognitive impairment. Indeed, for variants Glu413Gly and Cys461Phe, our model predicts negative shifts in the glutamate affinity and changes in the kinetic behavior, consistent with experimental data. These results point to the predictive power of this multiscale viewpoint, which aims to integrate the quantitative kinetic description of large interaction networks typical of system biology approaches with a focus on the quality of a few, key, molecular interactions typical of structural biology ones.


Asunto(s)
Región CA1 Hipocampal/metabolismo , Modelos Biológicos , Receptores AMPA/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Sinapsis/metabolismo , Transmisión Sináptica , Algoritmos , Relación Dosis-Respuesta a Droga , Glutamatos/metabolismo , Glutamatos/farmacología , Simulación de Dinámica Molecular , Mutación , Plasticidad Neuronal/fisiología , Conformación Proteica , Células Piramidales/metabolismo , Receptores AMPA/química , Receptores AMPA/genética , Receptores de Glutamato/metabolismo , Receptores de N-Metil-D-Aspartato/química , Receptores de N-Metil-D-Aspartato/genética , Relación Estructura-Actividad , Potenciales Sinápticos
9.
Inorg Chem ; 59(17): 12564-12577, 2020 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-32806003

RESUMEN

The cationic enantiopure (R,R) and luminescent Eu(III) complex [Eu(bisoQcd)(H2O)2] OTf (with bisoQcd = N,N'-bis(2-isoquinolinmethyl)-trans-1,2-diaminocyclohexane N,N'-diacetate and OTf = triflate) was synthesized and characterized. At physiological pH, the 1:1 [Eu(bisoQcd)(H2O)2]+ species, possessing two water molecules in the inner coordination sphere, is largely dominant. The interaction with bovine serum albumin (BSA) was studied by means of several experimental techniques, such as luminescence spectroscopy, isothermal titration calorimetry (ITC), molecular docking (MD), and molecular dynamics simulations (MDS). In this direction, a ligand competition study was also performed by using three clinically established drugs (i.e., ibuprofen, warfarin, and digitoxin). The nature of this interaction is strongly affected by the type of the involved heteroaromatic antenna in the Eu(III) complexes. In fact, the presence of isoquinoline rings drives the corresponding complex toward the protein superficial area containing the tryptophan residue 134 (Trp134). As the main consequence, the metal center undergoes the loss of one water molecule upon interaction with the side chain of a glutamic acid residue. On the other hand, the similar complex containing pyridine rings ([Eu(bpcd)(H2O)2]Cl with bpcd = N,N'-bis(2-pyridylmethyl)-trans-1,2-diaminocyclohexane N,N'-diacetate) interacts more weakly with the protein in a different superficial cavity, without losing the coordinated water molecules.


Asunto(s)
Complejos de Coordinación/química , Complejos de Coordinación/metabolismo , Europio/química , Hidrocarburos Aromáticos/química , Albúmina Sérica Bovina/metabolismo , Animales , Bovinos , Simulación de Dinámica Molecular , Unión Proteica , Conformación Proteica , Albúmina Sérica Bovina/química , Estereoisomerismo , Agua/química
10.
Molecules ; 25(24)2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-33333836

RESUMEN

Advances in coarse-grained molecular dynamics (CGMD) simulations have extended the use of computational studies on biological macromolecules and their complexes, as well as the interactions of membrane protein and lipid complexes at a reduced level of representation, allowing longer and larger molecular dynamics simulations. Here, we present a computational platform dedicated to the preparation, running, and analysis of CGMD simulations. The platform is built on a completely revisited version of our Martini coarsE gRained MembrAne proteIn Dynamics (MERMAID) web server, and it integrates this with other three dedicated services. In its current version, the platform expands the existing implementation of the Martini force field for membrane proteins to also allow the simulation of soluble proteins using the Martini and the SIRAH force fields. Moreover, it offers an automated protocol for carrying out the backmapping of the coarse-grained description of the system into an atomistic one.


Asunto(s)
Internet , Proteínas de la Membrana/química , Simulación de Dinámica Molecular , Proteínas de la Membrana/metabolismo , Conformación Proteica
11.
Int J Mol Sci ; 20(4)2019 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-30795536

RESUMEN

Mainstream approaches that are currently used as anti-aging therapies primarily explore the senescence and epigenetic drift aging hallmarks and they are at two ends of the spectrum. While senolytic therapies include either the selective elimination of senescent cells or the disruption of their secretome with the use of drugs or natural compounds, cellular reprogramming uses genetic manipulation to revert cells all the way back to pluripotency. Here, we describe the progress that has been made on these therapies, while highlighting the major challenges involved. Moreover, based on recent findings elucidating the impact of mitotic shutdown and aneuploidy in cellular senescence, we discuss the modulation of mitotic competence as an alternative strategy to delay the hallmarks of aging. We propose that a regulated rise in mitotic competence of cells could circumvent certain limitations that are present in the senolytic and reprogramming approaches, by acting to decelerate senescence and possibly restore the epigenetic landscape.


Asunto(s)
Reprogramación Celular , Longevidad/genética , Mitosis , Animales , Senescencia Celular/genética , Epigénesis Genética , Terapia Genética/métodos , Humanos
12.
Ecotoxicology ; 25(1): 121-31, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26496930

RESUMEN

The effect of the fungicide pyrimethanil (0.7 mg L(−1)) on biofilm development and alder leaf litter decomposition in aquatic ecosystems was assessed in outdoor lentic mesocosms immediately and 274 days after pyrimethanil application. Pyrimethanil decreased ergosterol concentrations (an indicator of fungal biomass) and the abundance and richness of the macroinvertebrate community associated with decomposing leaves. However, because neither fungi nor macroinvertebrates were main factors contributing to decomposition in this particular system, organic matter processing rates were not affected. After 274 days, pyrimethanil concentration in the water column was ≤0.004 mg L(−1) but richness, biomass and composition of the invertebrate community associated with decomposing leaf-litter still showed the effect. The comparison of ergosterol (a molecule existing on both algae and fungal cell membranes), with chlorophyll (an indicator of algal biomass) associated with biofilm suggests that pyrimethanil may decrease fungal biomass and alter the relative abundance of algae and fungi on biofilm developing in control- and treated-mesocosms.


Asunto(s)
Fenómenos Fisiológicos Bacterianos/efectos de los fármacos , Biopelículas/efectos de los fármacos , Fungicidas Industriales/metabolismo , Compuestos Orgánicos/metabolismo , Pirimidinas/metabolismo , Contaminantes Químicos del Agua/metabolismo , Relación Dosis-Respuesta a Droga , Estanques/química , Estanques/microbiología , Portugal , Estaciones del Año
13.
Ecotoxicology ; 25(2): 412-8, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26680766

RESUMEN

Since mudsnails are able to avoid contaminated sediment and that the contaminants in sediment are not uniformly distributed, the mudsnail Peringia ulvae was exposed to cadmium (Cd) spiked sediment and assessed for avoidance response in a heterogeneous contamination scenario. Four Cd concentrations were prepared and disposed in patches on dishes, which were divided in 25 fields (six fields for each sediment concentration); 24 organisms were deployed in the central field, with no sediment. Observations were made at 2, 4 and 6 h (corresponding to immediate response), 8, 10 and 12 h (very short term), and 24 h (short term). A trend to avoid contaminated patches was observed in the immediate and very short term. After 24 h exposure, the organisms exposed to the highest level of contamination seemed to have lost the ability to move and avoid contaminated patches. In a contamination scenario in which non- and contaminated sediment patches are heterogeneously distributed, local mudsnail populations can simply rearrange their locality without needing to move to a different habitat. Such less contaminated patches can become donor areas in a future recolonization scenario.


Asunto(s)
Cadmio/toxicidad , Sedimentos Geológicos/análisis , Caracoles/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Animales , Cadmio/análisis , Ecosistema , Monitoreo del Ambiente , Caracoles/fisiología , Contaminantes Químicos del Agua/análisis
14.
Glob Chang Biol ; 21(5): 1871-86, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25382269

RESUMEN

There is growing concern that modifications to the global environment such as ocean acidification and increased ultraviolet radiation may interact with anthropogenic pollutants to adversely affect the future marine environment. Despite this, little is known about the nature of the potential risks posed by such interactions. Here, we performed a multifactorial microcosm experiment to assess the impact of ocean acidification, ultraviolet B (UV-B) radiation and oil hydrocarbon contamination on sediment chemistry, the microbial community (composition and function) and biochemical marker response of selected indicator species. We found that increased ocean acidification and oil contamination in the absence of UV-B will significantly alter bacterial composition by, among other things, greatly reducing the relative abundance of Desulfobacterales, known to be important oil hydrocarbon degraders. Along with changes in bacterial composition, we identified concomitant shifts in the composition of oil hydrocarbons in the sediment and an increase in oxidative stress effects on our indicator species. Interestingly, our study identifies UV-B as a critical component in the interaction between these factors, as its presence alleviates harmful effects caused by the combination of reduced pH and oil pollution. The model system used here shows that the interactive effect of reduced pH and oil contamination can adversely affect the structure and functioning of sediment benthic communities, with the potential to exacerbate the toxicity of oil hydrocarbons in marine ecosystems.


Asunto(s)
Cambio Climático , Estuarios , Sedimentos Geológicos/microbiología , Microbiota/fisiología , Modelos Biológicos , Contaminación por Petróleo/efectos adversos , Secuencia de Bases , Cartilla de ADN/genética , Deltaproteobacteria/metabolismo , Deltaproteobacteria/efectos de la radiación , Hidrocarburos/análisis , Concentración de Iones de Hidrógeno , Microbiota/efectos de los fármacos , Datos de Secuencia Molecular , Portugal , Análisis de Secuencia de ADN , Rayos Ultravioleta
15.
Environ Res ; 134: 242-50, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25173058

RESUMEN

In situ assays based on feeding depression have been proposed as sublethal assays able to assess immediate contaminant effects on key ecosystem functions, long before effects on life-history traits can be detected. The in situ peculiarities provide more realistic exposure scenarios than laboratory-controlled conditions, which is particularly relevant for estuarine ecosystems where environmental conditions are highly variable. In this context, we developed a short-term cost-effective in situ assay based on the postexposure feeding of the estuarine species, Cyathura carinata, through the following steps: i) develop a methodology to quantify feeding under laboratory conditions; ii) quantify the sensitivity of the postexposure feeding response under laboratory conditions; iii) deploy the in situ assay at various field sites covering different environmental variables in a reference estuary and degrees of contamination in a contaminated estuary to, respectively, derive a model to predict postexposure feeding rates across sites varying in environmental variables and evaluate the potential of this in situ tool to assess sediment contamination in estuaries. A quantity of 100 defrosted nauplii of Artemia franciscana per isopod given during a short period of 30 min in darkness was adequate to allow estimating precise postexposure feeding rates. Laboratory toxicity tests showed the high sensitivity of postexposure feeding to Cd as a sublethal endpoint for C. carinata (7-fold lower than the corresponding 48-h LC50). However, this species appears to be able to face high concentrations of non-essential metals as Cd, with 96-h LC50 values (37 mg Cd/L) higher than values reported for other isopods, and among the highest concentrations reported for saltwater invertebrates. Results of in situ deployments at reference sites indicated that sediment with size fraction between 63-125 µm (very fine sand) influences feeding rates. The in situ assay across contaminated sites was able to discriminate between unpolluted and polluted estuaries, and also to detect degrees of toxicity among sampling sites within an estuary, after statistically adjusting feeding rates on the basis of the proportion of the sediment very fine sand influencing baseline feeding rates. The in situ postexposure feeding assay with C. carinata was found to be, therefore, a potential useful cost-effective tool for estuarine sediment toxicity assessments.


Asunto(s)
Conducta Alimentaria/efectos de los fármacos , Sedimentos Geológicos/química , Isópodos/fisiología , Contaminantes Químicos del Agua/toxicidad , Animales , Cadmio/toxicidad , Estuarios
16.
Ecotoxicol Environ Saf ; 103: 36-44, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24562181

RESUMEN

The present study aimed to assess the environmental fate of the insecticide and nematicide ethoprophos in the soil-water interface following the pesticide application in simulated maize and potato crops under Mediterranean agricultural conditions, particularly of irrigation. Focus was given to the soil-water transfer pathways (leaching and runoff), to the pesticide transport in soil between pesticide application (crop row) and non-application areas (between crop rows), as well as to toxic effects of the various matrices on terrestrial and aquatic biota. A semi-field methodology mimicking a "worst-case" ethoprophos application (twice the recommended dosage for maize and potato crops: 100% concentration v/v) in agricultural field situations was used, in order to mimic a possible misuse by the farmer under realistic conditions. A rainfall was simulated under a slope of 20° for both crop-based scenarios. Soil and water samples were collected for the analysis of pesticide residues. Ecotoxicity of soil and aquatic samples was assessed by performing lethal and sublethal bioassays with organisms from different trophic levels: the collembolan Folsomia candida, the earthworm Eisenia andrei and the cladoceran Daphnia magna. Although the majority of ethoprophos sorbed to the soil application area, pesticide concentrations were detected in all water matrices illustrating pesticide transfer pathways of water contamination between environmental compartments. Leaching to groundwater proved to be an important transfer pathway of ethoprophos under both crop-based scenarios, as it resulted in high pesticide concentration in leachates from Maize (130µgL(-1)) and Potato (630µgL(-1)) crop scenarios, respectively. Ethoprophos application at the Potato crop scenario caused more toxic effects on terrestrial and aquatic biota than at the Maize scenario at the recommended dosage and lower concentrations. In both crop-based scenarios, ethoprophos moved with the irrigation water flow to the soil between the crop rows where no pesticide was applied, causing toxic effects on terrestrial organisms. The two simulated agricultural crop-based scenarios had the merit to illustrate the importance of transfer pathways of pesticides from soil to groundwater through leaching and from crop rows to the surrounding soil areas in a soil-water interface environment, which is representative for irrigated agricultural crops under Mediterranean conditions.


Asunto(s)
Agricultura , Biota/efectos de los fármacos , Compuestos Organotiofosforados/metabolismo , Compuestos Organotiofosforados/toxicidad , Contaminantes del Suelo/toxicidad , Suelo/química , Agua/química , Aire/análisis , Animales , Artrópodos/efectos de los fármacos , Productos Agrícolas , Daphnia/efectos de los fármacos , Concentración 50 Inhibidora , Región Mediterránea , Oligoquetos/efectos de los fármacos , Organotiofosfatos , Reproducción/efectos de los fármacos , Contaminantes del Suelo/análisis , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
17.
Ecotoxicol Environ Saf ; 108: 89-94, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25042250

RESUMEN

Contaminants can behave as toxicants, when toxic effects are observed in organisms, as well as habitat disturbers and fragmentors, by triggering avoidance responses and generating less- or uninhabited zones. Drift by stream insects has long been considered a mechanism to avoid contamination by moving to most favorable habitats. Given that exploration and transportation of crude oil represent a threat for surrounding ecosystems, the key goal of the present study was to assess the ability of autochthonous groups of aquatic insects from the Ecuadorian paramo streams to avoid by drift different concentrations of polycyclic aromatic hydrocarbons (PAH) contained in the soluble fraction of locally transported crude oil. In the laboratory, different groups of insects were exposed to PAH for 12h. Three different assays, which varied in taxa and origin of the organisms, concentrations of PAH (0.6-38.8µgL(-1)), and environment settings (different levels of refuge and flow) were performed. For Anomalocosmoecus palugillensis (Limnephilidae), drift was a major cause of population decline in low concentration treatments but at higher concentrations mortality dominated. PAH was highly lethal, even at lower concentrations, for Chironomidae, Grypopterygidae (Claudioperla sp.) and Hydrobiosidae (Atopsyche sp.), and, therefore, no conclusion about drift can be drawn for these insects. Contamination by PAH showed to be a threat for benthic aquatic insects from Ecuadorian paramo streams as it can cause a population decline due to avoidance by drift and mortality.


Asunto(s)
Ecosistema , Insectos/efectos de los fármacos , Petróleo/toxicidad , Ríos , Contaminantes Químicos del Agua/toxicidad , Animales , Chironomidae/efectos de los fármacos , Monitoreo del Ambiente , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/toxicidad , América del Sur , Movimientos del Agua
18.
Ecotoxicology ; 23(5): 851-60, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24652239

RESUMEN

Tadpoles of two amphibian species, the neotropical anuran Leptodactylus latrans and the North American bullfrog Lithobates catesbeianus, were used in experiments to assess their preferred spatial distribution along habitat gradients and, thus, to what extent contamination by the fungicide pyrimethanil could trigger active spatial avoidance. The tadpoles were tested in a non-confined multi-compartment static system with a pyrimethanil contamination gradient through which organisms could move freely. Two samples, with and without (reference) pyrimethanil contamination, taken from outdoor mesocosms, were assayed. Tadpoles showed to be able to detect and move to the most favorable environment by preferring compartments containing reference mesocosm water. Pyrimethanil concentrations from 0.2 to 1.4 mg L(-1) were below lethal levels, but acted as habitat disturber since spatial avoidance was triggered. Avoiders of L. latrans reached almost 50 % at 1.4 mg L(-1). The present data reinforces the hypothesis regarding the risk of plant protection products to act, not only as toxicants, but also as habitat disturber, potentially leading to avoidance-driven population decline of amphibians.


Asunto(s)
Anuros , Conducta Animal/efectos de los fármacos , Fungicidas Industriales/toxicidad , Pirimidinas/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Ecosistema , Larva/efectos de los fármacos
19.
Ecotoxicology ; 23(7): 1254-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24898412

RESUMEN

Several oil spills due to ruptures in the pipeline oil systems have occurred at the Andean paramo. A sample of this crude oil was mixed with water from a nearby Andean lagoon and the toxicity of the soluble fraction was assessed through lethal and avoidance assays with a locally occurring copepod (Boeckella occidentalis intermedia). The integration of mortality and avoidance aimed at predicting the immediate decline of copepod populations facing an oil leakage. The 24-h median lethal PAH concentration was 42.7 (26.4-91.6) µg L(-1). In the 12-h avoidance assay, 30% avoidance was recorded at the highest PAH concentration (19.4 µg L(-1)). The mortality at this PAH concentration would be of 25% and, thus, the population immediate decline would be of 55%. The inclusion of non-forced exposure testing with the quantification of the avoidance response in environmental risk assessments is, therefore, supported due to underestimation of the lethal assays.


Asunto(s)
Copépodos/fisiología , Contaminación por Petróleo , Petróleo/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Copépodos/efectos de los fármacos , Dosificación Letal Mediana
20.
Obes Surg ; 34(2): 371-381, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38135740

RESUMEN

BACKGROUND: The "One-anastomosis transit bipartition" (OATB) is a promising emerging technique in the metabolic syndrome treatment. OBJECTIVE: To demonstrate the results achieved with OATB in the first 5 years after surgery. METHOD: Cross-sectional, retrospective study, with individuals undergoing primary OATB. Individuals included in the study were: ≥ 18 years, BMI ≥ 35 kg/m2; and excluded smoking habits, drug dependence, inflammatory bowel diseases. The data analyzed demographic, anthropometric, surgical, clinical, and nutritional. RESULTS: Sixty eight participants, 75% women, average age 45.5 years and BMI 41 kg/m2. Associated diseases: osteoarthritis (52.9%), hypertension (48.5%) and type 2 diabetes mellitus-T2DM (39.7%). All underwent laparoscopy, without conversions. Average operative time is 122.6 ± 31.7 min, and hospital stay is 2.2 ± 0.8 days. The common channel length 27 and 41 patients with 250 cm and 300 cm respectively. We registered no intraoperative complications, 2 (2.9%) early complications, and 14 (20.6%) late complications. In the first 6 months, 94.7% (250 cm) and 88.9% (300 cm) of the patients no longer used medication for T2DM, with no statistical difference between the two groups. The incidence of nutritional disorders at any time during follow-up: hypovitaminosis D (14.7%), folate hypovitaminosis (14.7%), elevated PTH (7.4%), hypoproteinemia (5.9%) and anemia (5.9%). We found no statistically significant difference between 250 and 300 cm common channel groups. CONCLUSION: We conclude that OATB is a safe and effective technique, demonstrating good control of T2DM and metabolic syndrome. There is a requirement to treat previous nutritional deficits. We need more long-term evidence and comparison to other surgical techniques.


Asunto(s)
Diabetes Mellitus Tipo 2 , Síndrome Metabólico , Trastornos Nutricionales , Obesidad Mórbida , Humanos , Femenino , Persona de Mediana Edad , Masculino , Obesidad Mórbida/cirugía , Diabetes Mellitus Tipo 2/cirugía , Diabetes Mellitus Tipo 2/complicaciones , Síndrome Metabólico/complicaciones , Estudios Retrospectivos , Estudios Transversales , Gastrectomía/métodos , Anastomosis Quirúrgica/métodos
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