Selenium is an essential micronutrient required for cellular antioxidant systems, yet at higher doses it induces oxidative stress. Additionally, in vertebrates environmental exposures to toxic levels of selenium can cause paralysis and death. Here we show that selenium-induced oxidative stress leads to decreased cholinergic signaling and degeneration of cholinergic neurons required for movement and egg-laying in Caenorhabditis elegans.
View Article and Find Full Text PDFObjective: Previous studies have demonstrated the benefit of the differential outcomes procedure (DOP) in human learning. In the present study we aimed to explore whether the DOP might also help to overcome the face recognition memory deficit commonly observed in Alzheimer's disease (AD) patients.
Method: A delayed matching-to-sample task was used.
Prostaglandin levels in different tissues and cyclooxygenase (COX-2) gene expression were compared between wild and cultured Senegalese sole (Solea senegalensis) broodstock in which a significantly different fatty acid profile, particularly lower tissue levels of arachidonic acid (ARA, 20:4n-6) and higher levels of eicosapentaenoic acid (EPA, 20:5n-3) in the cultured fish compared to wild had already been described. This is the first report of the COX-2 mRNA expression in Senegalese sole. Cyclooxygenase (COX-2) mRNA expression and prostaglandin (2- and 3-series) levels were determined in tissues from 32 broodstock fish, 16 (8 males and 8 females) from each origin wild and cultured (G1).
View Article and Find Full Text PDFOxidative damage is a common and early feature of Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis (ALS), and other neurodegenerative disorders. Dr. Mark Smith and his colleagues have built the case for oxidative stress being a primary progenitor rather than a secondary end-stage epiphenomenon of neurodegeneration.
View Article and Find Full Text PDFBackground: Recreational cannabis use and alcohol binge drinking are the most common drug consumption patterns in young adults. Impulsivity and several psychopathological signs are increased in chronic drug users, but the implications of recreational use are still poorly understood.
Methods: We evaluated impulsivity, sensation-seeking traits, impulsive decision-making, inhibitory control and possible symptoms of depression, anxiety and psychosis in three groups of young university adults: recreational cannabis users (N=20), alcohol binge drinkers (N=22) and non-drug users (N=26).
The objective of the study was to acclimatise wild-caught meagre (Argyrosomus regius) to captivity to produce viable eggs for aquaculture production. Twelve meagre (3 males and 9 females, mean weight = 20 ± 7 kg) were caught and transported to a land-based facility on 26 October 2006. During, March to June 2007, all three males were spermiating and five of the nine females were in vitellogenesis with mean maximum oocyte diameter ≥550 μm.
View Article and Find Full Text PDFSleep deprivation reduces vigilance or arousal levels, affecting the efficiency of certain cognitive functions such as learning and memory. Here we assessed whether the differential outcomes procedure (DOP), a learning procedure that has proved useful to ameliorate episodic memory deficits, can also improve memory performance in sleep-deprived participants. Photographs were presented as sample faces.
View Article and Find Full Text PDFMutations in Cu,Zn superoxide dismutase (SOD1) cause familial amyotrophic lateral sclerosis (FALS), a rapidly fatal motor neuron disease. Mutant SOD1 has pleiotropic toxic effects on motor neurons, among which mitochondrial dysfunction has been proposed as one of the contributing factors in motor neuron demise. Mitochondria are highly dynamic in neurons; they are constantly reshaped by fusion and move along neurites to localize at sites of high-energy utilization, such as synapses.
View Article and Find Full Text PDFA novel and more convenient method for the indium-promoted allylation of glyoxylic oximes based on the use of ultrasonic waves is reported. A similar procedure was used to develop the first example reported in the literature of an indium-mediated Reformatsky reaction on oxime ethers.
View Article and Find Full Text PDFPrevious studies have demonstrated that discriminative learning is facilitated when a particular outcome is associated with each relation to be learned. When this training procedure is applied (the differential outcome procedure; DOP), learning is faster and more accurate than when the more common non-differential outcome procedure is used. This enhancement of accuracy and acquisition has been called the differential outcome effect (DOE).
View Article and Find Full Text PDFJ Exp Zool A Ecol Genet Physiol
January 2012
Although the fatty acid (FA) requirements of marine teleosts not only are a function of the amount of each FA individually, but also of the relative proportions of the FAs; mostly, the interactions have been ignored and merely limited to a few interrelations of 20:4[n-6], 20:5[n-3], and 22:6[n-3]. To address this shortcoming, viable eggs of Dentex dentex were obtained from broodfish in captivity. Nine viability parameters (VP) (i.
View Article and Find Full Text PDFNearly 230 species of biting midges have been recorded or described from Argentina; 38 of them are known from the Buenos Aires province and only one is cited from Martín García Island. This paper presents the results raised from six collecting trips which took place on the island during spring 2005, summer 2006 and autumn 2009. Diverse sampling sites including permanent and temporary aquatic environments were chosen, most of the ten sampling sites were ponds of diverse origin, some of these environments were covered with floating vegetation as Lemna gibba, Lemna minuscule, Salvinia biloba, Salvinia minima, Azolla filiculoides, Limnobium laevigatum, Pistia stratiotes, Spirodela intermedia, Wolffiella oblonga and Wolffia columbiana.
View Article and Find Full Text PDFComp Biochem Physiol A Mol Integr Physiol
February 2012
The present study aimed to deepen the understanding of molecular mechanisms governing the absorption and metabolism of some nutrients, growth and development in larvae of Senegalese sole (Solea senegalensis) fed with Artemia enriched with Easy Selco (ES, INVE) or Aquagrow Gold (AGG, ABN), which mainly differed in their vitamin A (VA) content and fatty acid composition. The expression profile of genes involved in VA metabolism (crbp2, rbp, crabp1), lipid transport (i-fabp, l-fabp), nuclear receptors for VA and fatty acids (rarα1, rxrα, pparβ), growth (igf1, igf2 and their receptor igf1r) and development (bgp) was analyzed at 22, 30 and 38 days post hatching. The main results suggested that the amount of VA absorbed by larvae is controlled at the intestinal level by crbp2 in both groups, preventing excessive accumulation of this vitamin in the target tissues.
View Article and Find Full Text PDFThe Wnt pathway inhibitors DKK1 and sclerostin (SOST) are important therapeutic targets in diseases involving bone loss or damage. It has been appreciated that Wnt coreceptors LRP5/6 are also important, as human missense mutations that result in bone overgrowth (bone mineral density, or BMD, mutations) cluster to the E1 propeller domain of LRP5. Here, we report a crystal structure of LRP6 E1 bound to an antibody, revealing that the E1 domain is a peptide recognition module.
View Article and Find Full Text PDFTo better understand the role of bats as reservoirs of Bartonella spp., we estimated Bartonella spp. prevalence and genetic diversity in bats in Guatemala during 2009.
View Article and Find Full Text PDFThis study provides a comprehensive description of the main morphological and histological events that take place during larval and post-larval development of Senegal sole Solea senegalensis in order to establish a reference for its normal developmental organogenesis. Five stages have been described. Before gill development at the onset of metamorphosis (eye migration process, stage 4c), the skin was the main site of gas and ion exchange, whereas during stages 3 and 4, the skin begins differentiating into the definitive juvenile structure.
View Article and Find Full Text PDFThe archaeal exosome contains three heterodimeric RNase PH subunits, forming a hexamer with RNase activity; on top sits a trimer of two different SI domain proteins. In animals and yeast, six different, but related subunits form the RNase PH-like core, but these lack enzyme activity; there are three different Si-domain proteins and enzyme activity is provided by the endo/exonuc lease Rrp44 or-mainly in the nuclear exosome-the Rnase D enzyme Rrp6. Trypanosomes diverged from yeast and mammals very early in eukaryotic evolution.
View Article and Find Full Text PDFFree Radic Biol Med
September 2011
Cerium oxide nanoparticles (nanoceria) are widely used as catalysts in industrial applications because of their potent free radical-scavenging properties. Given that free radicals play a prominent role in the pathology of many neurological diseases, we explored the use of nanoceria as a potential therapeutic agent for stroke. Using a mouse hippocampal brain slice model of cerebral ischemia, we show here that ceria nanoparticles reduce ischemic cell death by approximately 50%.
View Article and Find Full Text PDFSince the timing of the lipovitellin heavy chain (LvH) of vitellogenin Ab (VtgAb) degradation during marine teleosts ontogeny is poorly understood, the current study was planned to address some aspects of this shortcoming. Fertilized eggs (before epiboly) of Dentex dentex were analysed. Vtg-derived proteins, that appeared as 6 protein bands after SDS-PAGE, were purified using specific ion exchange chromatography.
View Article and Find Full Text PDFReduced brain metabolism is an invariant feature of Alzheimer Disease (AD) that is highly correlated to the decline in brain functions. Decreased activities of key tricarboxylic acid cycle (TCA) cycle enzymes may underlie this abnormality and are highly correlated to the clinical state of the patient. The activity of the α-ketoglutarate dehydrogenase complex (KGDHC), an arguably rate-limiting enzyme of the TCA cycle, declines with AD, but the mechanism of inactivation and whether it can be reversed remains unknown.
View Article and Find Full Text PDFBackground: A new influenza A (H1N1) virus was first found in April 2009 and proceeded to cause a global pandemic. We compare the epidemiology and clinical presentation of seasonal influenza A (H1N1 and H3N2) and 2009 pandemic influenza A (H1N1) (pH1N1) using a prospective surveillance system for acute respiratory disease in Guatemala.
Methodology/findings: Patients admitted to two public hospitals in Guatemala in 2008-2009 who met a pneumonia case definition, and ambulatory patients with influenza-like illness (ILI) at 10 ambulatory clinics were invited to participate.
Acta Psychol (Amst)
January 2011
It has been widely demonstrated that the differential outcomes procedure (DOP) facilitates both the learning of conditional relationships and the memory for the conditional stimuli in animal subjects. For conditional discriminations in humans, the DOP also produces an increase in the speed of acquisition and/or final accuracy. However, the potential facilitative effects of differential outcomes in human memory have not been fully assessed.
View Article and Find Full Text PDFAquacultured fish gilthead seabream (Sparusaurata), previously exposed to low levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) trough the diet for a 13 months period, were fed on a clean feed for another 22 months. Gilthead seabream is a protandrous hermaphrodite species and this "decontamination" period coincided with the stages of sex differentiation, maturity and reproduction of the fish. PCDD/F levels in the fish tissues (i.
View Article and Find Full Text PDFThis study examined the role of coping with social stressors in the development of depressive symptoms, as well as gender differences in this process. Participants included 978 adolescents (aged 14-18 years), who completed measures of social stressors, coping responses, and depressive symptoms at the beginning of the study and measures of depressive symptoms at a six-month follow-up. High levels of disengagement and low levels of secondary control coping predicted a residual increase in depressive symptoms at follow-up.
View Article and Find Full Text PDF