Mitochondrial inhibitors activate influx of external Ca2+ in sea urchin sperm

AbstractSea urchin sperm have a single mitochondrion which, aside from its main ATP generating function, may regulate motility, intracellular Ca2+ concentration ([Ca2+]i) and possibly the acrosome reaction (AR). We have found that acute application of agents that inhibit mitochondrial function via differing mechanisms (CCCP, a proton gradient uncoupler, antimycin, a respiratory chain inhibitor, oligomycin, a mitochondrial ATPase inhibitor and CGP37157, a Na+/Ca2+ exchange inhibitor) increases [Ca2+]i with at least two differing profiles. These increases depend on the presence of extracellular Ca2+, which indicates they involve Ca2+ uptake and not only mitochondrial Ca2+ release. The plasma membrane permeation pathways activated by the mitochondrial inhibitors are permeable to Mn2+. Store-operated Ca2+ channel (SOC) blockers (Ni2+, SKF96365 and Gd2+) and internal-store ATPase inhibitors (thapsigargin and bisphenol) antagonize Ca2+ influx induced by the mitochondrial inhibitors. The results indicate that the functional status of the sea urchin sperm mitochondrion regulates Ca2+ entry through SOCs. As neither CCCP nor dicycloexyl carbodiimide (DCCD), another mitochondrial ATPase inhibitor, eliminate the oligomycin induced increase in [Ca2+]i, apparently oligomycin also has an extra mitochondrial target

Propiedades de las rocas volcánicas de Canarias (España) utilizadas como material de escollera

In the Canary Islands, there is a wide spectrum of volcanic rocks with different properties to be used in public works. The aim of this study is to analyse the physical-mechanical properties of all the volcanic rocks present in the Canary Island archipelago in order to determine their suitability for use in maritime construction works. The great variety of volcanic rocks present on the islands have been grouped into lithotypes based on similar geo-mechanical behaviour. The laboratory test results obtained for these lithotypes establish their suitability or not to be used as breakwater material in accordance with Spanish regulations.En el archipiélago canario existe un amplio espectro de rocas volcánicas con diferentes propiedades para ser utilizadas en obras públicas. El objetivo de este estudio es analizar las propiedades físico-mecánicas de todas las rocas volcánicas presentes en el archipiélago canario con el fin de determinar su idoneidad para ser utilizadas en obras de construcción marítima. La gran variedad de rocas volcánicas presentes en las islas, se han agrupado en litotipos basados en un comportamiento geomecánico similar. Los resultados de los ensayos de laboratorio obtenidos para estos litotipos establecen su idoneidad o no para ser utilizados como material de escollera de acuerdo con la normativa española

Ecosystem modeling to evaluate the ecological sustainability of small-scale fisheries: A case study from El Hierro, Canary Islands

This paper examines various fishery management scenarios based on the recovery of small-scale fisheries (SSF) following a submarine volcanic eruption in 2011 in El Hierro Island (Canary Islands, Spain). After this catastrophic event, the SSF composition of La Restinga fishing community was affected by socio-economic and demographic changes. The uncertainty derived from this situation provides an opportunity to evaluate the fisheries’ sustainability and advice on different management options under an ecosystem-based approach. The Ecopath with Ecosim modeling framework was used to build a model of El Hierro Island, where the versatile and traditional multispecies small-scale fleet of La Restinga operates. Our main goal is to improve traditional fisheries, based on the relevance of key local fisheries and multi-specific fishery strategies in the light of scientific knowledge. Temporal simulations for the next decade were analyzed by creating scenarios of alternative fishing effort distributions based on the fishing trends observed in El Hierro small-scale community of La Restinga after a natural hazard. The outcomes of this modeling prototype show the vulnerability of some littoral and demersal species, the resilience of migratory species, and the sustainability of SSF diversification practices. These results could develop an adaptive and co-management strategy with the local fishing community to preserve the small-scale fishing system and marine resources.En prens

Approaches for Removal of PAHs in Soils: Bioaugmentation, Biostimulation and Bioattenuation

Polycyclic aromatic hydrocarbons (PAHs)‐contaminated soils have been a concern during last decades; consequently, physicochemical and biological technologies have emerged and evolved with the aim of remediating them. Particularly, biological technologies are considered promising since they are low cost, safe and environmentally friendly. However, their results so far have been diverse and scattered. This chapter includes a review of the current status on bioaugmentation, biostimulation and bioattenuation techniques, which have been applied in PAHs‐contaminated agricultural soils during the last decades. Successes and failures in PAHs remediation applied at microcosm and field levels are exhibited. Furthermore, the effects of microbial inoculum, the soil organic matter and the particle size of the aggregates on the PAHs’ availability and on the subsequent microbial biodegradation are reviewed. Finally, agricultural management systems are considered in the prediction of the behaviour and the end‐point of some contaminants, as well as in the success of applying a biological technique

Vivienda vernácula palafítica mayangna y miskitu de Nicaragua

El presente artículo describe elementos de la vivienda palafítica, como hecho ontológico. Lo anterior establece una relación de existencia influenciada por aspectos sociales, dividiéndose por su orden en económico (productivo), e ideológico (teológico, político, simbólico). Con base en lo anterior, se reflexionó sobre la prevalencia tipológica de la ubicación y la configuración arquitectónica de las viviendas, respecto a su relación con los aspectos sociales ideológicos. Para su comprobación se seleccionó, como objeto de estudio, las viviendas de las comunidades miskitu y mayangna de la región Atlántica de Nicaragua. Tras documentar aspectos etnográficos y antropológicos, se estableció la existencia de tres tipologías de hábitat palafítico relacionados con su cuerpo ideológico, atribuyéndose sus características al significado que tiene el habitante respecto a los elementos de su medio ambiente espiritual. Lo anterior explica el por qué, pese a que los pobladores están expuestos a situaciones de riesgo que inciden en su permanencia, asumen el modelo tradicional de hábitat

Analysis of Ostwald ripening in Ni-rich Ni–Ti alloys by diffusion couples

"The coarsening kinetics of gamma' precipitates in Ni-rich Ni-Ti alloys are studied using a Ni-11-5 wt% Ti and pure Ni diffusion couple. The formed concentration gradient allowed to study the aging process at 1023 K (750 degrees C) in Ni-rich Ni Ti alloys with Ti content from 8-62 to 11-15 wt% Ti. In general, during the coarsening of gamma' precipitates, the experimental coarsening kinetics do not fit well to the LSW or TIDC theoretical models and anomalous behaviour of coarsening rate constant (k(r)) associated with gamma' volume-fraction is confirmed at high values.

Utilidad diagnóstica de los marcadores de estrés oxidativo en artritis reumatoide precoz en pacientes no fumadores y anti-CCP negativos

Fundamento. A pesar del desarrollo de nuevos marcadores y cri- terios diagnósticos para la artritis reumatoide (AR), todavía mu- chos pacientes son diagnosticados tras varios años de síntomas. Los marcadores de estrés oxidativo se incrementan ya en una fase temprana de la enfermedad. El objetivo del presente estudio fue evaluar el valor diagnóstico adicional de estos marcadores. Método. Se realizó un estudio de casos y controles. Los pacien- tes reclutados para el estudio cumplían los criterios para AR de la ACR 1987, todos ellos tenían menos de 2 años de síntomas y sin tratamiento previo con fármacos modificadores de la enfer- medad antirreumática (DMARD), esteroides o vitamina E. Los controles fueron seleccionados de los familiares del paciente y pareados (1:1) por sexo, edad, hábito tabáquico actual. Los marcadores de daño oxidativo que se midieron fueron malo- nildialdehído (MDA), hidroperóxidos lipídicos (LOOH) y pro- teínas carboniladas (CP). El Análisis estadístico se realizó de acuerdo con la STARD. resultados. Se incluyeron sesenta y cinco pacientes con AR sin tratamiento y 65 controles sanos. LOOH, CP, los anticuerpos con péctidos citrulinados (anti-CCP) y el factor reumatoide (FR) fueron significativamente mayores en los pacientes, y MDA fue mayor en los controles. Los mismos resultados se obtuvieron en los subgrupos de pacientes que fuman o no, y en anti-CCP positivos o negativos. El valor diagnóstico de los marcadores tradicionales mostró una buena especificidad pero una baja sensibilidad. La construcción de los modelos logísti- cos con la adicción de LOOH y CP aumenta la sensibilidad y el área bajo la curva ROC, especialmente en los no fumadores (66%) y los pacientes negativos ante-CCP (51%). conclusiones. Al incorporar LOOH o CP a los marcadores de la enfermedad tradicionales en AR, bien por separado o ambos conjuntamente, mejoró el diagnóstico de AR, especialmente en los pacientes no fumadores o aquellos con anticuerpos anti- CCP negativos.background. Besides the development of new markers and di- agnostic criteria for rheumatoid arthritis (RA), many patients are still diagnosed after several years of symptoms. Oxidative stress markers are already increased at an early stage of RA. Our aim was to evaluate the additional diagnostic value of these markers. Methods. A case-control study was performed. Patients met the 1987 RA ACR criteria, less than 2 years of symptoms and no previous treatment with disease-modifying anti-rheumatic drugs (DMARD), steroids or vitamin E. Controls were select- ed from patient’s relatives and matched (1:1) by gender, age, and current smoking habit. Oxidative damage markers were malonyldialdehyde (MDA), Lipid hydroperoxides (LOOH) and Carbonyl proteins (CP). Statistical analysis was performed in agreement with the STARD initiative. results. Sixty-five RA patients without treatment and 65 healthy controls were included. LOOH, CP, antibodies against citrullinated peptides (anti-CCP) and rheumatoid factor (RF) were significantly higher in patients, and MDA higher in con- trols. The same results were obtained in the subgroups of pa- tients who smoke or not, and in anti-CCP positive or negative. The diagnosis performance of traditional markers showed good specificity but low sensitivity. The addition of LOOH and CP increased the sensitivity and the area under the receiving operating characteristic (ROC) curve especially in non-smok- ing (66%) and negative anti-CCP (51%) patients. conclusions. The separate or combined addition of LOOH or CP to the traditional disease markers improved the diag- nosis of RA, especially in non-smoking or negative anti-CCP patients

Effects of the dietary supplementation of copper on growth, oxidative stress, fatty acid profile and skeletal development in gilthead seabream (Sparus aurata) larvae

The effect of dietary copper (Cu) levels on growth, oxidative stress, fatty acid profile and bone health of gilthead seabream larvae (Sparus aurata) was studied in 47 days-post-hatching fish fed 4 experimental diets containing 17, 18, 19 and 25 mg Cu/kg diet. After 21 days of feeding, larval growth and survival were not affected by the dietary Cu levels. However, larvae fed the non-supplemented diet (17 mg Cu/kg) showed clear symptoms of Cu deficiency, including increased lipid peroxidation and reduced bone mineralization. Increased peroxidation risk caused a reduction in essential fatty acids and n-3 PUFA (polyunsaturated fatty acids) contents in whole body lipids, whereas the poor vertebral body mineralization in seabream larvae was related to a marked increase in abdominal vertebrae anomalies. On the contrary, dietary Cu supplementation raised whole-body contents in DHA, EPA and n-3 PUFA and reduced MUFA, TBARS and the incidence of severe, cranial, branchiostegal rays and abdominal vertebral anomalies. Polynomial regression models applied to all these parameters suggested optimum dietary Cu levels to be 21.5–22.6 mg/kg in gilthead seabream larvae microdiets supplemented with CuSO4.5H2O. These levels (21.5–22.6 mg/kg) are in the range of the Cu contents in copepods (12–38 mg/kg) and on the verge of the dietary levels authorized by EU Commission in feeds for cultured fish species (25 mg Cu/kg diet)