Publications by authors named "Santamaria A"

Manganese (Mn) is an essential element present in all living organisms and is naturally present in rocks, soil, water, and food. Exposure to high oral, parenteral, or ambient air concentrations of Mn can result in elevations in Mn tissue levels and neurological effects. However, current understanding of the impact of Mn exposure on the nervous system leads to the hypothesis that there should be no adverse effects at low exposures, because Mn is an essential element; therefore, there should be some threshold for exposure above which adverse effects may occur and adverse effects may increase in frequency with higher exposures beyond that threshold.

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In this study, we reproduced two toxic models resembling some motor/kinetic deficits of Huntington's disease induced by bilateral intrastriatal injections of either quinolinic acid (QUIN, 120 nmol/microl per side) or 3-nitropropionic acid (3-NP, 250 nmol/microl per side) to rats. Motor skills (including total distance walked/traveled and total horizontal and vertical activities) were evaluated in a box-field system at 1 and 7 days post-lesion. In order to investigate whether these alterations were associated with the oxidative/nitrergic stress evoked by the nitrogen reactive species peroxynitrite (ONOO(-)) in the striatum, some rats were pretreated with the ONOO(-) decomposition catalyst iron porphyrinate (Fe(TPPS), 10 mg/kg, i.

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Background And Objective: Because of high fatality rate associated with acute infection by hepatitis A virus (HAV) in chronic hepatitis C patients, it is of interest to know the prevalence of immunization against HAV in these patients.

Patients And Method: Immunoglobulin G (IgG) IgG HAV antibodies (IgG anti-HAV) were determined in 313 hepatitis C virus antibodies (anti-HCV) positive patients and in 313 anti-HCV negative subjects (control group). Several epidemiological factors were recorded (age, sex, rural vs urban precedence, tattoos, parenteral drugs use, alcohol consumption and surgery).

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Conventional condensers using rotational symmetric devices perform far from their theoretical limits when transferring optical power from sources such as arc lamps or halogen bulbs to the rectangular entrance of homogenizing prisms (target). We present a free-form condenser design (calculated with the SMS method) that overcomes the limitations inherent to rotational devices and can send to the target 1.8 times the power sent by an equivalent elliptical condenser for a 4:1 target aspect ratio and 1.

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Sensors have been widely used for disease diagnosis, environmental quality monitoring, food quality control, industrial process analysis and control, and other related fields. As a key tool for sensor data analysis, machine learning is becoming a core part of novel sensor design. Dividing a complete machine learning process into three steps: data pre-treatment, feature extraction and dimension reduction, and system modeling, this paper provides a review of the methods that are widely used for each step.

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Alterations in motor activity related to dopamine changes in some brain regions have been described as consequences of the modifications produced by systemic administration of MK-801 (a noncompetitive NMDA receptor antagonist) in rats. Acetaldehyde (ACH), the main metabolite of ethanol, has been implicated in different alterations in the central nervous system after ethanol ingestion. ACH might exert some control on dopaminergic transmission through the formation of other compounds with dopamine, which eventually may modify dopamine content and its metabolism.

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Experimental evidence on the protective properties of S-allylcysteine (SAC) was collected from three models exerting striatal toxicity. In the first model, SAC (120 mg kg(-1)x5) prevented lipoperoxidation (LP) and mitochondrial dysfunction (MD) in synaptosomal fractions from 1-methyl-4-phenyl-1,2,3,6-tetrahydropiridinium-treated mice (30 mg kg(-1)), but without complete restoration of dopamine levels. In the second model, SAC (300 mg kg(-1)x 3), prevented LP and MD in synaptosomes from rats infused with 6-hydroxydopamine (8 microg microl(-1)) into the substantia nigra pars compacta, but again, without total reversion of depleted dopamine levels.

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The objective of the present study was to evaluate the amount of some potential health-promoting phenols in the grape of Vitis vinifera cv. Cesanese d'Affile and in wines made from these grapes. The analyses were performed using HPLC/DAD/MS.

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Background: Haplotypes A1 and A3 in the endothelial protein C receptor gene are tagged by the 4678G/C and 4600A/G polymorphisms, respectively, and have been reported to influence the risk of venous thromboembolism. We assessed whether these haplotypes modify the risk of premature myocardial infarction.

Design And Methods: We genotyped these polymorphisms in 689 patients with premature myocardial infarction and 697 control subjects.

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Purposes: To describe the visual manifestations of brain neoplasms, and to analyze the effect of tumor control on these.

Methods: This is a descriptive retrospective study, which includes patients under 14 years of age, suffering from different brain neoplasms in our hospital between 1996 and 2005 inclusive.

Results: In the group of patients with low visual acuity, 44% had organic amblyopias.

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The aim of this study was to precise the relationships of the auriculotemporal nerve in the infratemporal and parotid regions. We realized micro-dissections of thirty-two infratemporal and parotid regions of human cadaver's formol-fixed. The pattern of origin was: one root: 15.

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It has been recently demonstrated that the reactive nitrogen species (RNS) peroxynitrite (ONOO(-)) is involved in the neurotoxic pattern produced by quinolinic acid in the rat brain [V. Pérez-De La Cruz, C. González-Cortés, S.

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The results obtained in the CAPRIE study in 1996 led to the introduction of the clopidogrel as a new antiplatelet drug in the secondary prevention of acute myocardial infarct (AMI), ischemic stroke (IS) and symptomatic peripheral artery disease (PAD). Clopidogrel showed a similar efficacy and safety than acetylsalicylic acid (ASA). More recently, the combined use of clopidogrel with ASA has evidenced a better protection than ASA alone in some patients: patients with past history of AMI, angina pectoris, intermittent claudication or PAD, IS or TIA, coronary bypass, and diabetes mellitus, patients on treatment with statins, and patients with symptomatic carotid stenosis >/=50%.

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Polo-like kinase 1 (Plk1) and Aurora A play key roles in centrosome maturation, spindle assembly, and chromosome segregation during cell division. Here we show that the functions of these kinases during early mitosis are coordinated through Bora, a partner of Aurora A first identified in Drosophila. Depletion of human Bora (hBora) results in spindle defects, accompanied by increased spindle recruitment of Aurora A and its partner TPX2.

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The sylvatic triatomine Rhodnius pallescens is considered to be the most important and widespread vector of Trypanosoma cruzi and Trypanosoma rangeli in Panama. However, its behavior and biological characteristics have only been partially investigated. Thus, to achieve sustainable and efficient control over Chagas disease in Panama, a better understanding of the ecology and biology of R.

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Microtubule-based motor proteins provide essential forces for bipolar organization of spindle microtubules and chromosome movement, prerequisites of chromosome segregation during the cell cycle. Here, we describe the functional characterization of a novel spindle protein, termed "CHICA," that was originally identified in a proteomic survey of the human spindle apparatus [1]. We show that CHICA localizes to the mitotic spindle and is both upregulated and phosphorylated during mitosis.

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Plasminogen is a hemostasis-related phenotype and is commonly implicated in thrombotic and bleeding disorders. In the San Antonio Family Heart Study (SAFHS), we performed to our knowledge the first genomewide linkage scan for quantitative trait loci (QTLs) that influence the level of plasminogen. The subset of the SAFHS population used for this study consists of 629 individuals distributed across 26 extended Mexican American families.

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Excessive calcium is responsible for triggering different potentially fatal metabolic pathways during neurodegeneration. In this study, we evaluated the role of calcium on the oxidative damage produced in an in vitro combined model of excitotoxicity/energy deficit produced by the co-administration of quinolinate and 3-nitropropionate to brain synaptosomal membranes. Synaptosomal fractions were incubated in the presence of subtoxic concentrations of these agents (21 and 166 microm, respectively).

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The present paper reports on the production of anthocyanins and xanthones in different in vitro systems of Hypericum perforatum var. angustifolium (sin. Fröhlich) Borkh.

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Kynurenine pathway is gaining more and more attention every day in biomedical research since this catabolic route for tryptophan decomposition is not only implicated in different neurological disorders, but also possesses neuroactive metabolites with different biological properties, such as pro-oxidant and antioxidant regulators. Thus, the intensive research on this metabolic pathway is helping us to understand those mechanisms underlying neurodegenerative events during the occurrence of pathological process in the central nervous system (CNS), thereby allowing the design of potential therapies for those disorders involving excitotoxic, oxidative and inflammatory components. Here we intend to provide a brief overview on the relevance of this route for several CNS disorders, and discuss recent information on the different biological properties of the neuroactive metabolites of this pathway and their significance for further research.

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Excitotoxicity and disrupted energy metabolism are major events leading to nerve cell death in neurodegenerative disorders. These cooperative pathways share one common aspect: triggering of oxidative stress by free radical formation. In this work, we evaluated the effects of the antioxidant and energy precursor, levocarnitine (L-CAR), on the oxidative damage and the behavioral, morphological, and neurochemical alterations produced in nerve tissue by the excitotoxin and free radical precursor, quinolinic acid (2,3-pyrindin dicarboxylic acid; QUIN), and the mitochondrial toxin, 3-nitropropionic acid (3-NP).

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