Jorge Lago | ANFACO-CECOPESCA - Academia.edu (original) (raw)

Papers by Jorge Lago

Investigación: cultura, ciencia y tecnología, 2016

Food Control, Mar 1, 2012

Vibrio parahaemolyticus, Listeria monocytogenes and Salmonella spp. are important pathogens conta... more Vibrio parahaemolyticus, Listeria monocytogenes and Salmonella spp. are important pathogens contaminating seafood in China. In this study, we developed an efficient multiplex real-time PCR for the simultaneous detection of V. parahaemolyticus, L. monocytogenes and Salmonella spp. in raw shrimp without a prior enrichment step. In a test using 28 target and non-target strains only the targets were detected and two calibration curves, for pure cultures and artificially contaminated samples, were used to evaluate the efficiencies of this method. Amplification efficiencies of this multiplex real-time PCR were excellent in pure cultures and artificially contaminated shrimps. The limits of detection in artificially contaminated shrimps were 112 CFU/g for V. parahaemolyticus, 158 CFU/g for L. monocytogenes and 103 CFU/g for Salmonella spp. We validated this multiplex real-time PCR method on 48 commercial samples and the results were comparable to standard culture methods. This efficient multiplex real-time PCR, where each test takes only 50 min after DNA extraction, is a useful tool for high-throughput surveillance of V. parahaemolyticus, L. monocytogenes and Salmonella spp. in seafood products.

Journal of Agricultural and Food Chemistry, Jan 20, 2010

A comparative study was conducted to determine the feasibility of enzyme-linked immunosorbent ass... more A comparative study was conducted to determine the feasibility of enzyme-linked immunosorbent assays (ELISAs) for the detection of amnesic shellfish poisoning (ASP) and paralytic shellfish poisoning (PSP) toxins in nine naturally contaminated species in fresh, frozen, boiled and canned fish and shellfish. PSP and ASP were analyzed in 138 shellfish samples (mussels, clams, barnacles, razor shells, scallops and cockles) and anchovies by mouse bioassay (MBA) and high performance liquid chromatography with ultraviolet detection (HPLC-UV), respectively. Results were compared with toxin concentrations obtained using two commercial competitive ELISAs, saxitoxin and ASP kits. Immunoassays were able to quantify toxins in different matrices showing excellent Pearson&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s correlation coefficients (r = 0.974 for saxitoxin ELISA and r = 0.973 for ASP ELISA) and to detect PSP and ASP with a lower limit of detection (LOD), namely, 50 microg saxitoxin equivalent/kg shellfish meat for PSP and 60 microg/kg domoic acid in shellfish flesh for ASP, than the reference methods (350 microg saxitoxin equivalent/kg shellfish meat and 1.6 mg/kg domoic acid in shellfish flesh, respectively). These results suggest that the ELISA method could be used as screening systems in a variety of species without matrix interference.

Información del artículo Evidencia de Yessotoxinas en mejillón ("Mytilus galloprovincial... more Información del artículo Evidencia de Yessotoxinas en mejillón ("Mytilus galloprovincialis") de la Bahía de Alfacs, Delta del Ebro.

Cellular Signalling, 2001

The digitalic glicoside ouabain induces potentiation of rat mast cell histamine release in respon... more The digitalic glicoside ouabain induces potentiation of rat mast cell histamine release in response to several stimuli, which is mediated by Na+/Ca2+ exchanger. In this work, we studied the effect of ouabain on cytosolic calcium, intracellular pH and histamine release with Ca2+ ionophore A23187 in conditions designed to maximize ouabain-induced potentiation of rat mast cells response. The effect of protein kinase C (PKC), cAMP and phosphatase inhibition was also tested. Ouabain induced an enhancement in histamine release, cytosolic calcium and intracellular pH. The adenylate cyclase activator forskolin reduced the effect of ouabain on histamine release and intracellular pH, but enhanced the effect on cytosolic calcium. PKC activator PMA enhanced the effect of ouabain on histamine release and cytosolic calcium, without affecting intracellular pH. A PKC inhibitor, GF-109203X, reduced ouabain-induced enhancement of histamine release and intracellular pH, but increased the enhancement on cytosolic calcium. Finally, inhibition of protein phosphatases 1 and 2A with okadaic acid, increased the effect of ouabain on histamine release and intracellular pH, but reduced cytosolic calcium in presence of ouabain. This result suggest that ouabain-induced potentiation of rat mast cell histamine release with A23187 is modulated by kinases, and this modulation may be carried out by changes in intracellular alkalinization. However, the mechanism underlying cellular alkalinization remains to be elucidated.

Food and Chemical Toxicology, 2020

Paralytic shellfish poisoning (PSP) episodes cause important economic impacts due to closure of s... more Paralytic shellfish poisoning (PSP) episodes cause important economic impacts due to closure of shellfish production areas in order to protect human health. These closures, if are frequent and persistent, can seriously affect shellfish producers and the seafood industry, among others. In this study, we have developed an alternative processing method for bivalves with PSP content above the legal limit, which allows reducing toxicity to acceptable levels. A modification of the PSP detoxifying procedure stablished by Decision 96/77/EC of the European Union in Acanthocardia tuberculatum, was developed and implemented for PSP elimination in other species of bivalves. The procedure was applied to 6 batches of mussels, 2 batches of clams and 2 batches of scallops, achieving detoxification rates of around 85%. A viable industrial protocol which allows the transformation of a product at risk into a safe product was developed. Although a significant reduction was obtained, in a sample circa 9000 µg STX diHCl equiv/kg, the final toxin level in these highly toxic mussels did not fall below the European limit. The processing protocol described may be applied efficiently to mussels, clams and scallops and it may be a major solution to counteract the closure of shellfish harvesting areas, especially if persistent. Highlights  An industrial protocol aimed at reducing PSP toxin levels was developed and optimized in mussels, clams and scallops.  The procedure was applied to some batches of PSP-contaminated molluscs obtaining ± 85 % detoxification and a safe product.  However, one sample with an exceptionally high toxicity, 9000 µg STX diHCl equiv/kg, did not fall below the European limit.  An economically feasible bivalve canning processing was implemented, guaranteeing the manufacture of a safe product.

Cellular Physiology and Biochemistry, 1999

The Na+/Ca2+ exchanger has not been characterized in rat mast cells, although its existence has b... more The Na+/Ca2+ exchanger has not been characterized in rat mast cells, although its existence has been previously suggested. In this work, we determine that this exchanger exists on rat mast cells and that it has an important regulatory role on the cellular function. We have studied uptake and release of 45Ca in the presence of different external sodium concentrations and, under the same conditions, the simultaneous uptake of 22Na and 45Ca. The results show that uptake and release of 45Ca in these cells are related to the concentration of sodium in the extracellular medium and that there is also a perfect coupling between 22Na and 45Ca fluxes. In these conditions, we evaluated the intracellular calcium levels in fura-2 loaded cells. When the extracellular sodium concentration was lower than 60 mM, we observed an increase in intracellular calcium, reaching its maximum when the extracellular medium has no sodium. Then we investigated the effect on histamine release. The ionophore A23187 elicits histamine release in rat mast cells, depending on the extracellular calcium concentration. This drug releases more histamine (up to twofold) with sodium concentrations <60 mM. In the presence of 2,4-dichlorobenzamil hydrochloride, a Na+/Ca2+ exchanger inhibitor, the release of histamine induced by the ionophore was lower than in controls in media with low external sodium, and, on the contrary, at extracellular sodium concentrations >60 mM, the histamine release was higher than in controls. In the same conditions, but when the Na+-K+ ATPase was inhibited by ouabain, and as a consequence more sodium was inside the cells, a high increase in histamine release induced by A23187 in a sodium-free medium was observed. Under the same conditions, a high increase in intracellular calcium takes place. The overall data are preliminary evidence suggesting the existence of a Na+/Ca2+ exchanger in rat mast cells with a threshold to get reversed at 60 mM external sodium, lower concentrations of this ion increasing internal calcium and producing higher histamine release.

Dataset contains PSP levels (individual toxins and global toxicity) found in different batches of... more Dataset contains PSP levels (individual toxins and global toxicity) found in different batches of mussels, clams and scallops harvested during natural PSP blooms. Bivalves were processed with a protocol based on that stated in Decision 96/77/EC of the European Union which defines a protocol for PSP reduction in the giant cockle Acanthocardia tuberculatum (indicated as CE in data set). Molluscs were also processed (sterilization, pasteurization) without the detoxification steps (indicated as normal). Samples were analyzed in two different laboratories. These data contain results from the paper: Detoxification of paralytic shellfish poisoning toxins in naturally contaminated mussels, clams and scallops by an industrial procedure https://doi.org/10.1016/j.fct.2020.111386 Paz, Beatriz; Diogène, Jorge; Ferreres, Laura; Rambla-Alegre, Maria

Acofar: revista de la distribución farmacéutica cooperativista, 1996

In the frame of the SEAFOODTOMORROW project, a methodology for PSP elimina... more In the frame of the SEAFOODTOMORROW project, a methodology for PSP elimination from bivalve molluscs (mussels, clams and scallops) in processing industries has been developed, based on an already approved protocol at European Union (Decision 96/77/EC ) intended to eliminate these toxins in a particular species, the giant cockle Acanthocardia tuberculata. This protocol would allow the exploitation of molluscs with toxin concentration above the legislated level leading to a safe final product. Nevertheless, this protocol can not be immediately used by the processing industry, since when PSP level exceed the legislated limit, molluscs production areas are closed by competent authorities, and mollusc harvesting is banned. A legislative proposal regulating the conditions for harvesting and processing molluscs containing PSP concentrations above the legislated levels is presented.

Foods, 2021

The agri-food industry has historically determined the socioeconomic characteristics of Galicia a... more The agri-food industry has historically determined the socioeconomic characteristics of Galicia and Northern Portugal, and it was recently identified as an area for collaboration in the Euroregion. In particular, there is a need for action to help to ensure the provision of safe and healthy foods by taking advantage of key enabling technologies. The goals of the FOODSENS project are aligned with this major objective, specifically with the development of biosensors able to monitor hazards relevant to the safety of food produced in the Euroregion. The present review addresses the state of the art of analytical methodologies and techniques—whether commercially available or in various stages of development—for monitoring food hazards, such as harmful algal blooms, mycotoxins, Listeria monocytogenes, allergens, and polycyclic aromatic hydrocarbons. We discuss the pros and cons of these methodologies and techniques and address lines of research for point-of-care detection. Accordingly, th...

El ion Na+ es un componente fundamental del liquido extracelular. Sin embargo, su papel enla fisi... more El ion Na+ es un componente fundamental del liquido extracelular. Sin embargo, su papel enla fisiologia de las celulas no excitables ha sido poco estudiado. Los mastocitos de rata son celulas mononucleares granuladas que derivan de precursores hematopoyeticos. Sus granulos contienen histamina y otros mediadores de la inflamacion que se liberan mediante un proceso de exocitosis facilmente cuantificable, por lo que es un modelo de celulas no excitable ampliamente utilizado en estudios de senales de transduccion. El papel de calcio en el proceso de secrecion ha sido ampliamente estudiado, sin embargo, el papel de los iones monovalentes es menos conocido. El objetivo de este trabajo es estudiar el papel del ion Na+ en la fisiologia del mastocito de rata y su relacio con el Ca2+ y el pH celular en el proceso de secrecion. Para ello se estudio el efecto de la modificacion de la concentracion intra y extracelular de Na+ sobre la exocitosis y la concentracion intracelular de calcio y el pH ...

Environmental Toxicology and Pharmacology, 2011

Six species of marine sponges collected at intertidal and sublittoral sites of the coast of Galic... more Six species of marine sponges collected at intertidal and sublittoral sites of the coast of Galicia (NW Spain) were screened for potential cytotoxic properties on Neuroblastoma BE(2)-M17 cell line. Exposure to Halichondria panicea, Pachymatisma johnstonia, Ophlitaspongia seriata and Haliclona sp. aqueous extracts strongly affected cell appearance, inducing loss of neuronlike morphology and the formation of clumps. Extracts from these species also caused significant rates of cell detachment and decrease of mitochondrial membrane potential. Incubation with P. johnstonia, O. seriata and Suberites massa extracts also decreased the rate of cell proliferation. The increase of incubation time enhanced propidium iodide uptake by neuroblastoma cells. Toxic responses triggered by sponge extracts are compatible with apoptotic phenomena in neuroblastoma cells, even though increasing propidium uptake at long periods of exposure might indicate the induction of secondary necrosis. The cytotoxic properties of the tested extracts suggest the presence of compounds with potential pharmacological or biotechnological applications in the screened sponge species.

Toxins

Tetrodotoxin (TTX) is a potent neurotoxin that is receiving increasing interest in the European U... more Tetrodotoxin (TTX) is a potent neurotoxin that is receiving increasing interest in the European Union because it has been found in different fishery products (fish, bivalves and gastropods) captured in European waters. Since available information is scarce, further analytical data regarding the incidence of this toxin in European fishery products is needed in order to perform an appropriate risk assessment devoted to protecting consumers’ health. Hence, samples of bivalves and gastropods were collected at different points of the Spanish coast and analyzed by high-performance hydrophilic interaction liquid chromatography-tandem mass spectrometry (HILIC-MS/MS) to evaluate the presence of TTX. None of the analyzed samples showed TTX above an internal threshold of 10 µg/kg or even showed a peak under it. Our results on TTX occurrence obtained in bivalve molluscs and gastropods did not show, at least in the studied areas, a risk for public health. However, taking into account previous po...

Jat Journal of Applied Toxicology, Apr 1, 2008

Palytoxin isolated from the genus Palythoa is the most potent marine toxin known. The aim of the ... more Palytoxin isolated from the genus Palythoa is the most potent marine toxin known. The aim of the present study was to quantify palytoxin-induced cellular injury in the human intestinal cell line Caco-2. Cellular damage was measured by evaluating cell proliferation, cell membrane permeability, cell morphology and apoptotic markers. Furthermore, changes in F-actin were studied after exposure of cells to increasing amounts of palytoxin. The results show that cell proliferation decreased in a concentration-dependent manner with a mean IC 50 value of about 0.1 nM. A noticeable increase of cell detachment correlated with cell rounding and F-actin depolymerization was observed in palytoxin-treated cells. Moreover LDH was released from the cells in a dose and time dependent manner, although under these conditions there was no propidium iodide uptake. On the other hand, palytoxin impaired mitochondrial activity but other apoptotic markers, such as DNA fragmentation or caspases activation, were not observed. The results obtained in this paper suggest that the effects of palytoxin in Caco-2 cells were very potent and unspecific, since a primary necrosis and a secondary apoptosis seem to occur under these conditions.

Acofar Revista De La Distribucion Farmaceutica Cooperativista, 1995