Effectiveness of two probiotics in preventing necrotising enterocolitis in a cohort of very-low-birth-weight premature new-borns.

According to previous research, the incidence of necrotising enterocolitis (NEC) decreases after supplementation with probiotics. However, few studies have considered the equivalence or otherwise of different strains of probiotics in this respect. Accordingly, this prospective observational study was conducted in a cohort of 245 very-low-birth-weight (VLBW) new-borns to assess the prevalence of NEC after supplementation with the probiotic Inforan® (Berna Biotech, Madrid, Spain) 250 mg capsules containing 109 cfu of Lactobacillus acidophilus (ATCC 4356) and 109 cfu of Bifidobacterium bifidum (ATCC 15696); or with Bivos® (Ferring, Madrid, Spain) containing Lacticaseibacillus (formerly Lactobacillus) rhamnnosus (LGG) (ATCC 53103) (109 cfu); or with no probiotic supplementation. Statistical analysis was performed using multivariant regression for the duration of parenteral nutrition, length of neonatal intensive care unit stay, use of oxygen therapy and presence of chorioamnionitis. Of the VLBW new-borns in the study group, 65 received Infloran, 108 received Bivos and 72 received no probiotic. A significant association was observed between a reduced presence of NEC Stage ≥2 and probiotic supplementation. The odds risk (OR) obtained was 0.174 (95% confidence interval (CI): 0.032-0.936) for Infloran and 0.196 (95%CI: 0.053-0.732) for Bivos. Therefore, both probiotics are associated with a lower prevalence of NEC in VLBW new-borns, with no significant differences.

[Epidemiology of multiple sclerosis in Spain]. / Epidemiologia de la esclerosis multiple en España.

INTRODUCTION: Multiple sclerosis is a chronic autoimmune, inflammatory and neurodegenerative disease of the central nervous system and the most common non-traumatic disabling neurological disease in young adults. In the latest decades, multiple sclerosis is increasing worldwide, especially in women. The latitudinal distribution has been progressively attenuated. AIM: To review the epidemiological studies of multiple sclerosis in Spain to verify if this worldwide trend also occurs in Spain. DEVELOPMENT: We searched PubMed and Teseo databases using the search terms «epidemiology¼, «prevalence¼, «incidence¼, «multiple sclerosis¼ and «Spain¼. We selected articles published in Spanish and English between 1968 and 2018. CONCLUSIONS: Recent epidemiological studies confirm that Spain is a medium-high risk area for MS. The prevalence of MS has increased significantly throughout Spain in the latest years, especially in women, and recent studies show prevalence as high as 80-180 cases per 100,000.

TITLE: Epidemiologia de la esclerosis multiple en España.Introduccion. La esclerosis multiple es una enfermedad cronica autoinmune, inflamatoria y degenerativa del sistema nervioso central, y es el trastorno neurologico discapacitante no traumatico mas comun en adultos jovenes. Los estudios de prevalencia mas recientes indican que la frecuencia de la enfermedad ha aumentado en el mundo en las ultimas decadas, que dicho incremento de la prevalencia ocurre fundamentalmente a expensas de un mayor numero de casos de mujeres con formas remitentes, y que el gradiente latitudinal de la incidencia de la enfermedad se viene atenuando. Objetivo. Revisar los estudios sobre epidemiologia de esclerosis multiple en España para verificar si las tendencias mundiales se confirman en nuestro pais. Desarrollo. Busqueda bibliografica en las bases de datos PubMed y Teseo usando como palabras clave «epidemiology¼, «prevalence¼ e «incidence¼, cruzandolas con los terminos «multiple sclerosis¼ y «Spain¼; se realiza una seleccion inicial por titulo y resumen, en castellano e ingles, entre los años 1968 y 2018. Conclusiones. Un buen numero de estudios epidemiologicos recientes en España confirman que es una region de prevalencia media-alta de la enfermedad a lo largo de su geografia. Las cifras de prevalencia aumentan progresivamente a lo largo de las ultimas decadas hasta alcanzar en la actualidad 80-180 casos por 100.000 habitantes, y ello ha ocurrido a expensas de una mayor frecuencia de la enfermedad en las mujeres.

Transcranial direct-current stimulation (tDCS) improves detection of simple bright stimuli by amblyopic Long Evans rats in the SLAG task and produces an increase of parvoalbumin labelled cells in visual cortices.

In this work visual functional improvement of amblyopic Long Evans rats treated with tDCS has been assessed using the "slow angled-descent forepaw grasping" (SLAG) test. This test is based on an innate response that does not requires any memory-learning component and has been used before for measuring visual function in rodents. The results obtained show that this procedure is useful to assess monocular but not binocular deficits, as controls and amblyopic animals showed significant differences during monocular but not during binocular assessment. On the other hand, parvoalbumin labelling was analysed in three areas of the visual cortex (V1M, V1B and V2L) before and after tDCS treatment. No changes in labelling were observed after monocular deprivation. However, tDCS treatment significantly improved vision through the amblyopic eye, and a significant increase of parvoalbumin-positive cells was observed in the three areas, both in the stimulated hemisphere but also in the non-stimulated hemisphere. This effect occurred both in control and amblyopic animals. Thus, tDCS induced changes are similar in controls and amblyopic animals, although only the last one showed a functional improvement.

Eficacia y perfil de seguridad del arándano americano en lactantes y niños con infección urinaria recurrente / Efficacy and safety profile of cranberry in infants and children with recurrent urinary tract infection

Objetivo: La profilaxis con arándano americano de la infección de orina recurrente infantil se ha mostrado eficaz en el modelo experimental del adulto. Existen pocos datos sobre su eficacia, seguridad y dosis recomendadas en la población pediátrica. Métodos: Se desarrolla un ensayo clínico controlado, doble ciego en fase III en niños mayores de un mes de edad para evaluar la eficacia y seguridad del arándano americano en la infección urinaria recurrente infantil. Se parte del supuesto de no inferioridad del arándano americano frente a trimetoprima. El análisis estadístico se realiza mediante un análisis de Kaplan Meier. Resultados Se reclutan 85 pacientes menores de un año de edad y 107 mayores de un año. Setenta y cinco pacientes reciben arándano y 117 trimetoprima. El porcentaje acumulado de infección de orina asociado a la profilaxis con arándano en menores de un año fue de 46% (IC 95%: 23-70) en niños y del 17% (IC 95%: 0-38) en niñas, con eficacia a las dosis utilizadas inferior a trimetoprima. En los niños mayores de un año de edad el arándano se mostró no inferior a trimetoprima, con un porcentaje acumulado de infección de orina de 26% (IC 95%: 12-41). El arándano americano fue bien tolerado, no registrándose efectos adversos. Conclusiones: Nuestro estudio confirma que el arándano americano es seguro y eficaz en la profilaxis de infección urinaria recurrente en lactantes y niños. Con las dosis utilizadas su eficacia no es inferior a la observada para trimetoprima entre los mayores de un año de edad (AU)

Objective: Cranberry prophylaxis of recurrent urinary tract infection in infants has proven effective in the experimental model of the adult. There are few data on its efficacy, safety and recommended dose in the pediatric population. Methods: A controlled, double-blind Phase III clinical trial was conducted on children older than 1 month of age to evaluate the efficacy and safety of cranberry in recurrent urinary tract infection. The assumption was of the non-inferiority of cranberry versus trimethoprim. Statistical analysis was performed using Kaplan Meier analysis. Results: A total of 85 patients under 1 year of age and 107 over 1 year were recruited. Trimethoprim was prescribed to 75 patients and 117 received cranberry. The cumulative rate of urinary infection associated with cranberry prophylaxis in children under 1 year was 46% (95% CI; 23-70) in children and 17% (95% CI; 0-38) in girls, effectively at doses inferior to trimethoprim. In children over 1 year-old cranberry was not inferior to trimethoprim, with a cumulative rate of urine infection of 26% (95% CI; 12-41). The cranberry was well tolerated and with no new adverse effects. Conclusions: Our study confirms that cranberry is safe and effective in the prophylaxis of recurrent urinary tract infection in infants and children. With the doses used, their efficiency is not less than that observed for trimethoprim among those over 1 year-old (AU)

[Efficacy and safety profile of cranberry in infants and children with recurrent urinary tract infection]. / Eficacia y perfil de seguridad del arándano americano en lactantes y niños con infección urinaria recurrente.

OBJECTIVE: Cranberry prophylaxis of recurrent urinary tract infection in infants has proven effective in the experimental model of the adult. There are few data on its efficacy, safety and recommended dose in the pediatric population. METHODS: A controlled, double-blind Phase III clinical trial was conducted on children older than 1 month of age to evaluate the efficacy and safety of cranberry in recurrent urinary tract infection. The assumption was of the non-inferiority of cranberry versus trimethoprim. Statistical analysis was performed using Kaplan Meier analysis. RESULTS: A total of 85 patients under 1 year of age and 107 over 1 year were recruited. Trimethoprim was prescribed to 75 patients and 117 received cranberry. The cumulative rate of urinary infection associated with cranberry prophylaxis in children under 1 year was 46% (95% CI; 23-70) in children and 17% (95% CI; 0-38) in girls, effectively at doses inferior to trimethoprim. In children over 1 year-old cranberry was not inferior to trimethoprim, with a cumulative rate of urine infection of 26% (95% CI; 12-41). The cranberry was well tolerated and with no new adverse effects. CONCLUSIONS: Our study confirms that cranberry is safe and effective in the prophylaxis of recurrent urinary tract infection in infants and children. With the doses used, their efficiency is not less than that observed for trimethoprim among those over 1 year-old. (Clinical Trials Registry ISRCTN16968287).

Functionalization of carbon nanotubes by water plasma.

Multiwall carbon nanotubes grown by plasma enhanced chemical vapour deposition were functionalized by H(2)O plasma treatment. Through a controlled functionalization process of the carbon nanotubes (CNTs) we were able to modify and tune their chemical reactivity, expanding the range of potential applications in the field of energy and environment. In particular, different oxygen groups were attached to the surfaces of the nanotubes (e.g. carboxyl, hydroxyl and carbonyl), which changed their physicochemical properties. In order to optimize the main operational parameters of the H(2)O plasma treatment, pressure and power, a Box-Wilson experimental design was adopted. Analysis of the morphology, electrochemical properties and functional groups attached to the surfaces of the CNTs allowed us to determine which treatment conditions were suitable for different applications. After water plasma treatment the specific capacitance of the nanotubes increased from 23 up to 68 F g(-1) at a scan rate of 10 mV s(-1).

High sensitivity cardiac troponin T and interleukin-6 predict adverse cardiovascular events and mortality in anticoagulated patients with atrial fibrillation.

UNLABELLED: There are limited data on the prognostic role of biomarkers in anticoagulated patients with atrial fibrillation (AF). We evaluated the prognostic value of high sensitivity TnT (hsTnT) and high-sensitivity interleukin-6 (hsIL6) in a large cohort of AF patients taking oral anticoagulant therapy (OAC) as both biomarkers have been associated with adverse cardiovascular events. METHODS: We studied 930 patients (51% male; median age 76) with permanent/ paroxysmal AF who were stabilized (for at least 6 months) on OAC (INRs 2.0-3.0). Plasma hsTnT and hsIL6 levels were quantified by electrochemiluminescense immunoassay at baseline. Patients were followed-up for up to 2 years, and adverse events (thrombotic and vascular events, mortality and major bleeding) were recorded. RESULTS: At follow-up, 96 patients (3.97%/year) died whilst 107 had an adverse cardiovascular event (3.14%/year). On multivariate analysis, high hsTnT and high hsIL6 remained significantly associated with prognosis even after adjusting for CHADS2 score: HR 2.21 (1.46-3.35, P<0.001) for high hsTnT and 1.97 (1.29-3.02, P=0.002) for high hsIL6, for adverse cardiovascular events. For all-cause mortality, the HRs were 1.79 (1.13-2.83, P=0.013) and 2.48 (1.60-3.85, P<0.001), respectively. The integrated discrimination index (IDI) values of clinical scores (CHADS2 and CHA2 DS2-VASc) were improved by the addition of hsTnT and/or hsIL6 (all P<0.05). CONCLUSION: In a large 'real world' cohort of anticoagulated AF patients, both hsTnT and hsIL6 levels provided prognostic information that was complementary to clinical risk scores for prediction of long-term cardiovascular events and death, suggesting that these biomarkers may potentially be used to refine clinical risk stratification in AF.

New perspectives in antiplatelet therapy.

Platelet activation is a complex mechanism of response to vascular injury and atherothrombotic disease, leading to thrombus formation. A wide variety of surface receptors -integrins, leucine-rich family receptors, G protein coupled receptors, tyrosine kinase receptors- and intraplatelet molecules support and regulate platelet activation. They are potential targets of antiplatelet therapy for the prevention and treatment of arterial thrombosis. Despite the overall clinical benefit of established antiplatelet drugs targeting cyclooxigenase-1 (COX-1), glycoprotein integrin αIIbß3, and the purinergic P2Y(12) receptor of adenosine diphosphate, a significant proportion of treated patients continue to experience recurrent ischaemic events. This may be in partly attributed to insufficient inhibition of platelet activation. In addition, it should not be underestimated that these drugs are not immune from bleeding complications. The substantial progress in understating the regulation of platelet activation has played a key role in the development of novel antiplatelet agents. Current examples of drug under development and evaluation include: novel P2Y(12) receptor inhibitors (prasugrel, ticagrelor, cangrelor, and elinogrel), thrombin receptor PAR-1 antagonists (vorapaxar, atopaxar), new integrin glycoprotein IIb/IIIa inhibitors, and inhibitors targeting the thromboxane receptor (TP), phosphodiesterases, the collagen receptor glycoprotein VI, and intraplatelet signalling molecules. This review summarizes the mechanisms of action and current clinical evaluation of these novel antiplatelet agents.

Interactions between clopidogrel and proton pump inhibitors: a review of evidence.

Clopidogrel is a thienopyridine, which inhibits the platelet P2Y adenosine diphosphate (ADP) receptor termed P2Y(12). It is taken as a prodrug that requires biotransformation to an active metabolite by cytochrome P450 (CYP) isoenzymes. In addition, esterases shunt the majority of clopidogrel to an inactive pathway, whilst the remaining prodrug requires two separate CYP-dependent oxidative steps. PPIs might diminish the antiplatelet effects and the clinical effectiveness of clopidogrel possibly through inhibition of CYP2C19 and CYP3A4 isoenzymes. Treatment with clopidogrel and aspirin decreases recurrent cardiovascular events after an acute coronary syndrome. However, an inherent increment of major bleeding is also associated with antiplatelet therapy, as well as dyspepsia with aspirin. Also, major bleeding has been associated with high risk for ischemic events and mortality. For this reason, a proton pump inhibitor (PPI) is often co-prescribed to reduce the risk of gastrointestinal tract bleeding, but its concomitant use might reduce the inhibitory effect of clopidogrel on platelet aggregation. Nevertheless, doubts exist about the possible interaction of concomitant PPI use that may reduce the inhibitory effect of clopidogrel on platelet aggregation. Indeed, there is some controversy with regard to the true risk of cardiovascular adverse events arising from a potential drug-drug interaction between clopidogrel and PPI. In this article, we will review the current status and controversies in relation to a possible interaction between clopidogrel and PPIs.

Quantification and source identification of polycyclic aromatic hydrocarbons in core sediments from Sundarban mangrove wetland, India.

The distribution and potential sources of 16 polycyclic aromatic hydrocarbons (PAHs) in sediment cores (<63 microm particle size) of the Sundarban mangrove wetland, northeastern coast of Bay of Bengal (India), were investigated by gas chromatography coupled to mass spectrometry. The total concentrations of 16 PAHs ( summation operator(16)PAHs) ranged from 132 to 2938 ng/g, with a mean of 634 ng/g, and the sum of 10 out of 16 priority PAHs ( summation operator(10)PAH) varied from 123 to 2441 ng/g, with a mean of 555 ng/g, and the 5 carcinogenic PAHs (benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene, and dibenz[a,h]anthracene) accounted for 68-73% of the priority PAHs. Maximum concentrations of the sediment core were obtained at subsoil depth of 12-16 cm. The prevalence of four to six aromatic ring PAHs and cross-plots of specific isomer ratios such as phenanthrene/anthracene, fluoranthene/pyrene, and methylphenanthrenes/phenanthrene suggested the predominance of wood and coal combustion sources, the atmospheric deposition, and surface runoff to be the major transport pathways. A good correlation existed between the benzo[a]pyrene level and the total PAH concentrations, making this compound a potential molecular marker for PAH pollution. Total TEQ (S) (carc) values calculated for samples varied from 6.95 ng/g TEQ (S) (carc) to 119 ng/g TEQ (S) (carc) , with an average of 59 ng/g dry weight TEQ (S) (carc) . The baseline data can be used for regular monitoring, considering the industrial and agricultural growth around this coastal environment.

Development of a methodology for the simultaneous determination of inorganic and organolead compounds using supercritical fluid extraction followed by gas chromatography-mass spectrometry and its application to environmental matrices.

A method for the extraction of triethyl lead (TEL(+)), trimethyl lead (TML(+)), and Pb(2+) from sand was developed using supercritical modified CO(2)-CH(3)OH extraction and in situ complexation with sodium diethyldithiocarbamate (NaDDTC) using a 2(5) factorial exploratory design is described. The screened variables were (i) pressure (69-193 bar), (ii) temperature (40-150 degrees C), (iii) ligand amount (0-100 mg), (iv) methanol volume (0.0-0.5 mL) and (v) static time (0-45 min). The optimum extraction conditions found were as follow: pressure, 193 bar; temperature, 40 degrees C; amount of NaDDTC, 100 mg; methanol volume, 0.5 mL; static time 45 min; and CO(2) flow rate, 1 mL min(-1). Under these conditions the following recoveries were obtained (TML(+) 97+/-2%, TEL(+) 70+/-5%, and Pb(2+) 100+/-4%). The presence of NaDDTC is not necessary for the extraction of TML(+) and TEL(+), but it is a very significative parameter for Pb(2+). A second experimental design 2(2)+star for temperature and pressure was realized, but the results were not better than those of the first model. SFE extract derivatization was achieved with pentylmagnesium bromide, and target analyte determination was carried out by gas chromatography-mass spectrometry. Detection limits in the full-scan mode were 4, 10, and 39 pg as lead for TMPeL, TEPeL and PbPe(4), respectively. The method was validated with urban dust containing TML(+) (CRM 605. Pb 7.9 +/-1.2 microg kg(-1)) and river sediment containing inorganic lead (GBW08301. Pb 79.0+/-12.0 mg kg(-1)) as reference materials. The proposed method was applied to lead analysis in sand collected from an oil-polluted beach in Chile.

[Mechanisms of action of botulinum toxins and neurotoxins]. / Mécanismes d'action des toxines et neurotoxines botuliques.

Several bacteria of the Clostridium genus (C. botulinum) produce 150 kDa di-chainal protein toxins referred as botulinum neurotoxins or BoNTs. They associate with non-toxic companion proteins and form a complex termed botulinum toxin. BoNTs specifically inhibit vesicular neurotransmitter release. The cellular action of BoNTs can be depicted according to a multi-step model : The toxin's heavy chain mediates binding to specific receptors comprised of a ganglioside moiety and a vesicular protein (SV2 for BoNT type A, synaptotagmin for BoNT type B), followed by endocytotic internalisation of the BoNT/receptor complex. Vesicle recycling induces BoNT internalisation. Upon acidification of vesicles, the light chain of the neurotoxin is translocated into the cytosol. Here, this zinc-endopeptidase cleaves one or two among three synaptic proteins (VAMP-synapto-brevin, SNAP25, and syntaxin). As the three protein targets of BoNT play major role in fusion of synaptic vesicles at the release sites, their cleavage is followed by blockade of neurotransmitter exocytosis. Importantly, as the BoNT receptors and intracellular targets are present in all nerve terminals, the BoNTs are not specific for cholinergic transmission. Duration of their inhibitory action is mainly determined by the the life-time of the toxin's light chain in the cytosol. Sprouting of new nerve-endings, which are retracted when the poisoned nerve terminals have recovered full functionality, may lead to anticipated recovery of the poisoned nerve terminals.

Assessing human exposure to phthalic acid and phthalate esters from mineral water stored in polyethylene terephthalate and glass bottles.

Phthalic acid and phthalate esters are of growing interest due to their significant usage and potential toxicity. Polyethylene terephthalate (PET) and glass are both widely used materials for bottled drinking water. In this study, phthalic acid (PhA), bis(2-ethylhexyl) phthalate (DEHP), dimethyl phthalate (DMP), diethyl phthalate (DEP), diisobutyl phthalate (DiisoBP) and dibutyl phthalate (DBP) were analysed in a large number of Italian bottled water samples. These samples showed different concentrations of phthalates are nearly 20 times higher in samples bottled in PET than those from glass bottles with total levels of phthalates of 3.52 and 0.19 microg l(-1), respectively. However, the observed levels do not represent a significant exposure pathway when considering the US Environmental Protection Agency (USEPA) reference dose (an estimate of a daily oral exposure to the human population, including sensitive subgroups, that is likely to be without an appreciable risk of deleterious effects during a lifetime). In addition, no significant correlation was found between the phthalate concentrations and the physicochemical properties of the different water samples, apart from the still/sparkling water parameter for the PET samples. In this instance, slightly higher concentrations were observed for the PET bottled still water samples than for the sparkling water samples, although no explanation has been found yet.

[Transcranial magnetic stimulation: contributions to the study of the visual pathway]. / Estimulación magnética transcraneal: aportaciones al estudio de la vía visual.

INTRODUCTION: Most of our impressions of the world and our memory are based on sight. Being able to look around us and recognise our surroundings involves the activity of several processing pathways in the brain that interact with each other and integrate information until it becomes conscious. Little is known about all these mechanisms today and therefore new tools must be developed and employed to enable us to further our understanding in this field. DEVELOPMENT: The visual system is one of the most complex sensory systems. An important part of what we do know about how it is organised derives from studies carried out in animals or from clinical findings in patients with visual problems caused by local lesions. In recent years, advances in neurophysiological recording and stimulation techniques have made it possible to study visual functioning in a far more direct manner. Transcranial magnetic stimulation (TMS) is one of these new techniques and can be used to assess the excitability of the occipital cortex, induce conscious visual perceptions, produce 'virtual lesions' and even carry out direct manipulation of several visuoperceptual tasks. In this work we present the main applications of TMS in the study of the visual pathway, its most significant technical aspects and its clinical usefulness from the diagnostic point of view and within the field of visual rehabilitation. CONCLUSIONS: TMS is a safe technique with important clinical and therapeutic implications, which offers valuable data about the mechanisms underlying the processing of visual information, and it is therefore becoming a very useful tool within the areas of neuroscience and clinical neurology.

Estimulación magnética transcraneal: aportaciones al estudio de la vía visual / Transcranial magnetic stimulation: contributions to the study of the visual pathway

La mayor parte de nuestras impresiones del mundo y de nuestra memoria se basan en la visión. Observarnuestro entorno y reconocer aquello que nos rodea implica la actividad de varias vías de procesamiento cerebral que interactúan entre sí e integran la información hasta hacerla consciente. Todos estos mecanismos todavía se conocen mal, de ahí la necesidad de desarrollar y utilizar nuevas herramientas que permitan avanzar en este campo. Desarrollo. El sistema visual es uno de los más complejos sistemas sensoriales. Gran parte de lo que sabemos acerca de su organización deriva de estudios de experimentación animal o de hallazgos clínicos en pacientes con problemas visuales provocados por lesiones locales. En los últimos años, los avances en las técnicas neurofisiológicas de registro y estimulación han permitido el estudio dela función visual de un modo mucho más directo. La estimulación magnética transcraneal (EMT) es una de estas nuevas técnicas y permite valorar la excitabilidad de la corteza occipital, inducir percepciones visuales conscientes, producir ‘lesiones virtuales’ e incluso manipular directamente diversas tareas visuoperceptivas. En este trabajo se presentan las principalesaplicaciones de la EMT en el estudio de la vía visual, sus aspectos técnicos más relevantes y su utilidad clínica desde el punto de vista diagnóstico y en el ámbito de la rehabilitación visual. Conclusiones. La EMT es una técnica segura, con importantesimplicaciones clínicas y terapéuticas, que ofrece datos valiosos sobre las mecanismos que subyacen en el procesamiento de la información visual, por lo que se está convirtiendo en una herramienta de gran utilidad en el ámbito de la neurociencia y la neurología clínica

Most of our impressions of the world and our memory are based on sight. Being able to look aroundus and recognise our surroundings involves the activity of several processing pathways in the brain that interact with each other and integrate information until it becomes conscious. Little is known about all these mechanisms today and therefore new tools must be developed and employed to enable us to further our understanding in this field. Development. The visualsystem is one of the most complex sensory systems. An important part of what we do know about how it is organised derives from studies carried out in animals or from clinical findings in patients with visual problems caused by local lesions. In recentyears, advances in neurophysiological recording and stimulation techniques have made it possible to study visual functioning in a far more direct manner. Transcranial magnetic stimulation (TMS) is one of these new techniques and can be used to assessthe excitability of the occipital cortex, induce conscious visual perceptions, produce ‘virtual lesions’ and even carry out direct manipulation of several visuoperceptual tasks. In this work we present the main applications of TMS in the study of the visualpathway, its most significant technical aspects and its clinical usefulness from the diagnostic point of view and within the field of visual rehabilitation. Conclusions. TMS is a safe technique with important clinical and therapeutic implications, whichoffers valuable data about the mechanisms underlying the processing of visual information, and it is therefore becoming a very useful tool within the areas of neuroscience and clinical neurology

Improvements on a total mercury determination absorption spectrophotometry detection method in human hair using graphite-furnace atomic.

In this work, a methodology for the determination of total mercury in human hair is presented. This methodology is an improvement of a previous technique which has been reported by Chen et al. in 2002. This previous work was based on an acid digestion, C, cartridge clean-up, a 2,3-dimercaptopropane-1-sulfonate complexing agent, solid phase extraction and a graphite furnace atomic absorption spectrophotometric determination. In the present study, the complexing agent has been replaced by the ammonium pyrrolidine dithiocarbamate followed by a liquid-liquid extraction and the clean-up has been avoided in order to obtain a less expensive and less time consuming methodology.

Meralgia parestésica de presentación posquirúrgica / Postoperative meralgia paresthetica

No disponible

Development of a procedure for the determination of perfluorocarboxylic acids in sediments by pressurised fluid extraction, headspace solid-phase microextraction followed by gas chromatographic-mass spectrometric determination.

A procedure for the determination of perfluorocarboxylic acids (i.e. PFC7-10A) in sediment by pressurized fluid extraction (PFE), derivatization, headspace solid-phase microextraction and GC-MS determination in the negative ion chemical ionisation mode was developed. The PFE extraction variables such as solvent composition, number and time per extraction cycle, and extraction temperature were optimised. In the optimum extraction conditions, recoveries exceeding 95% with a limit of detection and RSDs of 0.5-0.8 ng g(-1) and 15.5-16.8%, respectively, were obtained. The developed analytical procedure was applied to harbour sediments where PFC8A and PFC10A were detected for the first time at low ppb concentrations (i.e. 8-11 ng g(-1).

Improvements in the methylmercury extraction from human hair by headspace solid-phase microextraction followed by gas-chromatography cold-vapour atomic fluorescence spectrometry.

Improvements in the methylmercury extraction from human hair by solid-phase microextraction followed by gas chromatography coupled to cold-vapour atomic fluorescence spectrometry (GC-CVAFS) have been carried out. They consisted in the optimisation of the digestion step prior to the aqueous-phase ethylation and in the GC-CVAFS interface set-up. The main digestion parameters such as acid type, concentration, temperature and time have been optimised for hair sample analysis, thereby avoiding methylmercury degradation. Moreover, the stability of the digested samples was evaluated to improve the sample throughput.