164 research outputs found
Palynological age constraint of Les Vilelles unit, Catalan Coastal Chain, Spain
Les Vilelles unit is a detrital sequence exposed at the southwestern margin of the Catalan Coastal Chain (CCC), NE Spain, below the Carboniferous turbiditic series. Based on the palynological content, the age of this unit was initially assigned to the Middle-Late Devonian (Eifelian to Famennian). Additional radiolarian and conodont findings were considered to be Early-Middle Mississippian (Tournaisian to early Visean). To clarify this age discrepancy a new and more comprehensive palynostratigraphic analysis has been conducted in the upper part of the section representative of Les Vilelles unit. This has provided an assemblage of miospores, acritarchs, prasinophyta phycomata and chitinozoans that can be confidently assigned to a latest Frasnian interval, in contact with the Frasnian-Famennian boundary. Therefore, the present analysis refines the Middle-Late Devonian age formerly assigned, establishes a latest Frasnian age for the top of the unit, and provides new insights to the better understanding of the unconformity and hiatus separating the pre-Carboniferous and Carboniferous CCC series in the Priorat Massif. The study also includes a systematic section with the description of three newly established miospore species: Dibolisporites coniugatum, Dibolisporites prioratum and Rugospora spinosa
Assessing the Potential of Algae Extracts for Extending the Shelf Life of Rainbow Trout (Oncorhynchus mykiss) Fillets
This study evaluates the potential of different algae extracts (Crassiphycus corneus, Cc; Ulva ohnoi, Uo; Arthrospira platensis, Ap; Haematococcus pluvialis, Hp) as additives for the preservation of rainbow trout fillets. The extracts were prepared with different water to ethanol ratios from the four algae species. The highest ferric reducing antioxidant power (FRAP) was observed in Uo extracted in 80% ethanol. Ap aqueous extract also had considerable FRAP activity, in agreement with a high total phenolic content. Radical scavenging activity (DPPH) was higher in Cc 80% ethanol extract, in agreement with a high total carotenoid content. In fact, when the algae aqueous extracts were assayed on the fish fillets, their antioxidant activity exceeded that of ascorbic acid (ASC). All algae extracts delayed microbial growth and lipid oxidation processes in trout fillets throughout the cold storage period compared to controls, and also improved textural parameters, these effects being more evident for Ap and Hp. With respect to the color parameters, the Hp extract prevented the a* values (redness) from decreasing throughout cold storage, a key point when it comes to colored species, not least salmonids. On the other hand, the Ap extract was not as effective as the rest of treatments in avoiding a* and b* decrease throughout the storage period, and thereby the color parameters were impaired. The results obtained, together with the natural origin and the viability for large-scale cultivation, make algae extracts interesting fish preservative agents for the food industry
Effect of Probiotics on Host-Microbiota in Bacterial Infections
Diseases caused by bacteria cause millions of deaths every year. In addition, the problem of
resistance to antibiotics is so serious that it threatens the achievements of modern medicine. This is a
very important global problem as some bacteria can also develop persistence. Indeed, the persistence
of pathogenic bacteria has evolved as a potent survival strategy to overcome host organisms’ defense
mechanisms. Additionally, chronic or persistent infections may be caused by persisters which could
facilitate antibiotic resistance. Probiotics are considered good bacteria. It has been described that the
modulation of gut microbiota by probiotics could have a great potential to counteract the deleterious
impact and/or regulate gut microbiota after bacterial infection. Probiotics might provide health
benefits through the inhibition of pathogen growth or the replacement of pathogenic bacteria. Bearing
in mind that current strategies to avoid bacterial persistence and prevent antibiotic resistance are not
effective, other strategies need to be assessed. We have carried out a comprehensive review, which
included the reported literature between 2016 and 2021, highlighting the clinical trials that reported
the probiotics’ potential to regulate gut microbiota after bacterial infection and focusing in particular
on the context of antibiotic resistance and persister cells.Regional Ministry of Health and Families (Andalucia, Spain) RPS 2466
The helminth community of Apodemus sylvaticus (Rodentia, Muridae) in the Sierra de Gredos (Spain)
[email protected] [email protected] [email protected] helmintiana de Apodemus sylvaticus (Rodentia, Muridae) en la Sierra de
Gredos (España).— Como parte de los estudios helmintofaunísiticos que sobre pequeños
mamíferos se están llevando a cabo en la península ibérica, la sierra española de
Gredos fue estudiada. La comunidad helmintiana del ratón de campo, Apdoemus
sylvaticus (Rodentia, Muridae), fue analizada. Cualitativamente, 13 especies de helmintos
fueron detectadas: Plagiorchis sp. I y Plagiorchis sp. II (Trematoda); Taenia parva larvae,
T. martis larvae, T. taeniaeformis larvae, Rodentolepis straminea y R. fraterna (Cestoda);
y Trichuris muris, Heligmosomoides polygyrus, Syphacia stroma, S. frederici, Aspiculuris
tetraptera y Rictularia proni (Nematoda). Cuantitativamente, destaca la mayor prevalencia(65,0%) y abundancia media (36,9%) de H. polygyrus. El análisis de los resultados
globales permite evidenciar, en comparación con otras sierras estudiadas, a pesar de las
adversas condiciones climáticas, la existencia de una helmintofauna diversa de la
especie hospedadora estudiada. Este hecho podría estar relacionado tanto con las
particulares características ecológicas como con el adecuado estado de conservación de
este ecosistema.The helminth community of Apodemus sylvaticus (Rodentia, Muridae) in the Sierra de
Gredos (Spain).— The Spanish mountain range of Gredos was included in the studies
conducted on the Iberian peninsula to investigate helminth fauna of small mammals.
The helminth community of the wood mouse, Apodemus sylvaticus (Rodentia, Muridae),
was analysed. Qualitatively, 13 helminth species were detected: Plagiorchis sp. I and
Plagiorchis sp. II (Trematoda); Taenia parva larvae, T. martis larvae, T. taeniaeformis
larvae, Rodentolepis straminea and R. fraterna (Cestoda); and Trichuris muris,
Heligmosomoides polygyrus, Syphacia stroma, S. frederici, Aspiculuris tetraptera and
Rictularia proni (Nematoda). Quantitatively, the highest prevalence (65.0%) and the mean
abundance (36.9%) of H. polygyrus stand out. In comparison with the other mountain
ranges studied, analysis of the global results demonstrates that the helminth fauna of the
host species studied is diverse despite the adverse climatic conditions. This could be
related to both the particular ecological characteristics and the appropriate state of
preservation of this ecosystem
Instrumental relacionado con el fuego y el banquete
El artículo da a conocer un pequeño lote de fragmentos de espetones de bronce procedentes de dos tumbas de la necrópolis de La Cerrada de los Santos (Aragoncillo) y de otro enterramiento del cementerio de Chera (Prados Redondos), todos ellos en la provincia de Guadalajara y pertenecientes al Celtibérico Antiguo. Estos hallazgos amplían el mapa de su reparto en la Península. El estudio se completa con un morillo de hierro, muy probablemente procedente de la necrópolis de El Atance, también en la provincia de Guadalajara. El trabajo da pie al estudio metalográfico de los ejemplares y a la reflexión sobre su significado en relación con los ritos de fuego y los banquete
Survey of the occurrence of Giardia duodenalis cysts and Cryptosporidium spp. oocysts in green leafy vegetables marketed in the city of Valencia (Spain)
The role of vegetables usually consumed without prior culinary treatment is known to contribute to the prevalence of foodborne diseases. Cysts and oocysts can contaminate food, which can then be the source of infection in humans. The aim of the study was to assess the occurrence of Giardia duodenalis and Cryptosporidium spp. (oo) cysts in green leafy vegetables marketed in the city of Valencia (Spain) combining parasitological methods, two real-time qPCRs and light microscopy. An experimental field study was conducted on 129 vegetable samples, 64 from conventional farms and 65 from ecological (organic) farms. The samples were washed with water, and the resulting solution after removing the vegetables, was subjected to 24-hour sedimentation. The concentrated sediment was used for the search for protozoa. A positive result by both real-time PCRs, or a positive result by one qPCR and confirmation by microscopy was established as a positivity criterion. Giardia duodenalis was detected in 23.0 % of the samples, and Cryptosporidium spp. in 7.8 %. G. duodenalis (41.5 %) and Cryptosporidium spp. (20.0 %) were more frequent in ecological crops. The high level of contamination detected in organic vegetables may be due to the type of fertilizers and the quality of the water used for their irrigation and reinforces the need to take extreme hygiene measures in vegetables that are consumed raw
Gene markers of dietary macronutrient composition and growth in the skeletal muscle of gilthead sea bream (Sparus aurata)
To increase our current knowledge on the nutritional regulation of growth and gene expression pattern in fish skeletal muscle, the effect of dietary macronutrient composition was assessed on digestibility, nutrient retention, growth performance, and the mRNA levels of key genes involved in functionality, growth and development of the skeletal muscle in gilthead sea bream (Sparus aurata). Long-term starvation decreased the expression of myogenic regulatory factors such as Myod2, Myf5, myogenin (Myog) and Myf6 in the skeletal muscle of S. aurata. The supply of high or medium protein, low carbohydrate diets enhanced growth parameters, feed efficiency ratio, feed conversion ratio and significantly upregulated myod2. However, the supply of low protein, high carbohydrate diets restricted growth and stimulated the mRNA levels of myostatin, while downregulated follistatin (fst), igf1, mtor and rps6. Microarray analysis revealed igfals, tnni2, and gadd45a as gene markers upregulated by diets enriched with protein, lipids and carbohydrates, respectively. The results of the present study show that in addition to myod2, fst, igf1, mtor and rps6, the expression levels of igfals, tnni2 and remarkably gadd45a in the skeletal muscle can be used as markers to evaluate the effect of dietary macronutrient changes on fish growth and muscle development in S. aurata.This work was supported by the Ministerio de Economía, Industria y Competitividad, Spain (grant no. AGL2016-78124-R; cofunded by the European Regional Development Fund, European Commission) and the Agencia Nacional de Investigacion ´ y Desarrollo, Chile (Becas Chile/ 2011–72111506). The authors thank Piscicultura Marina Mediterranea (Burriana, Castellon, ´ Spain) for providing S. aurata juveniles.Peer ReviewedPostprint (published version
Nematode Parasites of the European Pilchard, Sardina pilchardus (Walbaum, 1792): A Genuine Human Hazard?
The European pilchard is one of the most frequently consumed fish species in Mediterranean countries, especially in Italy and Spain, and has been reported as the cause of at least eight human anisakidosis cases in Spain since 1991, the parasitic disease caused by the ingestion of fish or cephalopods infested by the larval stage of anisakid nematodes. With the aim to shed light on the potential human parasitosis risk posed by these nematode larvae, we helminthologically analyzed a total of 350 sardines (European pilchard) captured in the Atlantic Ocean (175 sardines) and the Mediterranean Sea (175 specimens), acquired in various Spanish nationwide supermarket chains. The statistical analysis of some helminth parameters revealed a higher presence of nematodes belonging to the genus Hysterothylacium (frequency of parasitation of 24.29%; total mean parasite burden of 2.36), usually considered non-parasitic for humans (only three cases reported worldwide), when compared to nematodes of the genus Anisakis (5.71%; 0.16). The human anisakidosis risk after the consumption of raw or undercooked sardines and the role of Hysterothylacium, the most frequent nematode, is discussed, providing information to consumers. To avoid human infection by anisakid larval nematodes, the established preventive measures are confirmed and new ones are proposed
Prevalence and Risk of Anisakid Larvae in Fresh Fish Frequently Consumed in Spain: An Overview
Anisakidosis is a fish-borne zoonosis caused by parasitic nematodes of the family Anisakidae, of which the species belonging to Anisakis simplex complex are the most representative. It is considered an emerging disease in Spain. The objective of this study is to analyse the presence of larvae in fish frequently consumed in Spanish supermarkets, inferring the risk of infection. In total 1,786 specimens of 9 different fish species, from two geographical origins (Atlantic and Mediterranean), acquired fresh and not eviscerated were examined for anisakid nematodes. Analysis showed that 33.7% of the samples were parasitized by Anisakis larvae. The horse mackerel (Trachurus trachurus) presented the highest total prevalence (66.0%), followed by the silver hake (Merluccius bilinearis) (59.5%), the mackerel (Scomber scombrus) (58.4%), the blue whiting (Micromesistius poutassou) (53.9%) and the European hake (Merlucius merlucius) (45.0%). In general, the prevalence was higher in Atlantic than in Mediterranean fish. In all the species analysed, a higher presence of the parasite was detected in the viscera than in the flesh, although in the most parasitized species a noteworthy prevalence and abundance was observed in the flesh. In conclusion, risk factors, like fish species and origin, should be considered by consumers, in addition of following the recommendations established by Commission Regulation (EU) No1276/2011 and the Spanish Royal Decree 1420/2006
Anisakid Nematodes and Potential Risk of Human Anisakiasis through the Consumption of Hake, Merluccius spp., Sold Fresh in Spanish Supermarkets
Nematode parasite species belonging to the Anisakis simplex complex are the most important cause of human anisakiasis through the consumption of (mainly) undercooked, previously not frozen, or conveniently treated fish. In Spain, the consumption of hake has been recognized as an important source of this parasitosis. With the aim of shedding light on the risk factors that can influence the potential risk of human anisakiasis in Spain through the consumption of fresh hake sold by nationwide supermarket chains, a total of 536 small hake specimens belonging to the species Merluccius bilinearis caught off the Northeast American coasts and Merluccius merluccius caught in the Northeast Atlantic and Mediterranean waters was analysed. Anisakids morphologically identified as Anisakis type I were found as the most prevalent and the most abundant species and were considered the main potential cause of human anisakiasis. Intrinsic and extrinsic factors concerning the hake, such as its origin and season of capture, its size, as well as the days passed between its capture and consumption, should be taken into account to avoid this human parasitosis. It is essential that consumers have access to fish label information which should include, as regulated by the European Commission, traceability data
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