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1.
Front Neurol ; 12: 690402, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34177790

RESUMEN

In patients with congenital nystagmus (CN), the study of vestibular function is complicated by many factors related to the measurement of the vestibulo-ocular reflex (VOR) by means of caloric testing and the video head impulse test (vHIT), and to date no such studies have successfully employed the vHIT to evaluate vestibular function in these patients. We present a case with CN and vertigo in which peripheral vestibular function was evaluated using the vHIT system, including head impulse testing and the suppression head impulse protocol. We show that it is possible (a) to identify lateral VOR changes such as abnormalities resembling those produced by bilateral vestibular lesions, though not necessarily related to the same mechanism; (b) to identify peripheral VOR lesions of the vertical semicircular canals (SCC); and (c) to document compensation and recovery subsequent to these peripheral lesions during follow-up of patients with CN. vHIT is a useful tool that should be used to study vestibular function in patients with CN and vertigo, which could constitute a new clinical application of this technique.

2.
Environ Pollut ; 243(Pt B): 1861-1866, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30408874

RESUMEN

The use of the soil can alter its functionality and influence the (bio)availability of any contaminants present. Our study considers two types of agricultural soils, rainfed and olive soils, managed according to conventional practices that apply contaminants directly to the soil (fertilizers, pesticides, fungicides, etc.) and receive contaminants from the atmosphere (traffic, industry, etc.); and a forest soil that is not subject to these agricultural practices. In this scenario, we consider a mixture of 16 trace elements (As, Ba, Be, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Se, Sb, Sn, V and Zn), since their interactions with the soil can produce synergistic and/or antagonistic effects that are not considered in most studies. We studied whether the content and (bio)availability of low concentrations of a mixture of trace elements affect the soil functionality in terms of the activity of some key enzymes We analysed the total, potentially and immediately available fractions, the soil parameters and soil enzyme activity. The results show that the functionality of the soils studied was affected despite the low concentrations of trace elements. The highest concentrations of total trace elements and available fractions were found in forest soils compared to the other two uses. Soil enzyme activity is best explained by the potentially available fraction of a mixture of trace elements and physico-chemical soil variables. In our study, pH, total nitrogen, organic carbon and fine mineral particles (silt and clay) had an influence on soil enzyme activity and the (bio)available fractions of trace elements.


Asunto(s)
Enzimas/metabolismo , Microbiota/fisiología , Microbiología del Suelo , Suelo/química , Oligoelementos/química , Agricultura , Activación Enzimática/efectos de los fármacos , Fertilizantes , Plaguicidas/química , Plaguicidas/farmacología , Contaminantes del Suelo/química , Contaminantes del Suelo/farmacología , Oligoelementos/farmacología
3.
Sci Total Environ ; 551-552: 57-65, 2016 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-26874761

RESUMEN

Abandonment of vineyards after uprooting has dramatically increased in last decades in Mediterranean countries, often followed by vegetation expansion processes. Inadequate management strategies can have negative consequences on soil quality. We studied how the age and type of vegetation cover and several environmental characteristics (lithology, soil properties, vineyard slope and so on) after vineyard uprooting and abandonment contribute to the variation patterns in total, HAc (acetic acid-method, HAc) and EDTA-extractable (ethylenediaminetetraacetic acid-method) concentrations of Cd, Cu, Pb and Zn in soils. We sampled 141 points from vineyards and abandoned vineyard Mediterranean soils recolonized by natural vegetation in recent decades. The contribution of several environmental variables (e.g. age and type of vegetation cover, lithology, soil properties and vineyard slope) to the total and extractable concentrations of metals was evaluated by canonical ordination based on redundancy analysis, considering the interaction between both environmental and response variables. The ranges of total metal contents were: 0.01-0.15 (Cd), 2.6-34 (Cu), 6.6-30 (Pb), and 29-92mgkg(-1) (Zn). Cadmium (11-100%) had the highest relative extractability with both extractants, and Zn and Pb the lowest. The total and EDTA-extractable of Cd, Pb and Zn were positively related to the age of abandonment, to the presence of Agrostis castellana and Retama sphaerocarpa, and to the contents of Fe-oxides, clay and organic matter (OM). A different pattern was noted for Cu, positively related to vineyard soils. Soil properties successfully explained HAc-extractable Cd, Cu, Pb and Zn but the age and type of vegetation cover lost significance. Clay content was negatively related to HAc-extractable Cu and Pb; and OM was positively related to HAc-Cd and Zn. In conclusion, the time elapsed after vineyard uprooting, and subsequent land abandonment, affects the soil content and availability of metals, and this impact depended on the colonizing plant species and soil properties.


Asunto(s)
Monitoreo del Ambiente , Granjas , Metales/análisis , Contaminantes del Suelo/análisis , Agricultura , Cadmio/análisis , Cobre/análisis , Ácido Edético/análisis , Región Mediterránea , Suelo , Vino , Zinc/análisis
4.
Environ Toxicol Chem ; 34(1): 37-44, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25318656

RESUMEN

The contribution of the nature instead of the total content of soil parameters relevant to metal bioavailability in lettuce was tested using a series of low-polluted Mediterranean agricultural calcareous soils offering natural gradients in the content and composition of carbonate, organic, and oxide fractions. Two datasets were compared by canonical ordination based on redundancy analysis: total concentrations (TC dataset) of main soil parameters (constituents, phases, or elements) involved in metal retention and bioavailability; and chemically defined reactive fractions of these parameters (RF dataset). The metal bioavailability patterns were satisfactorily explained only when the RF dataset was used, and the results showed that the proportion of crystalline Fe oxides, dissolved organic C, diethylene-triamine-pentaacetic acid (DTPA)-extractable Cu and Zn, and a labile organic pool accounted for 76% of the variance. In addition, 2 multipollution scenarios by metal spiking were tested that showed better relationships with the RF dataset than with the TC dataset (up to 17% more) and new reactive fractions involved. For Mediterranean calcareous soils, the use of reactive pools of soil parameters rather than their total contents improved the relationships between soil constituents and metal bioavailability. Such pool determinations should be systematically included in studies dealing with bioavailability or risk assessment.


Asunto(s)
Carbonato de Calcio/análisis , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Suelo/química , Agricultura , Cadmio/análisis , Cobre/análisis , Contaminación Ambiental , Plomo/análisis , Zinc/análisis
5.
Environ Sci Pollut Res Int ; 21(9): 6176-87, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24477337

RESUMEN

Organic matter (OM) plays a key role in microbial response to soil metal contamination, yet little is known about how the composition of the OM affects this response in Mediterranean calcareous agricultural soils. A set of Mediterranean soils, with different contents and compositions of OM and carbonate and fine mineral fractions, was spiked with a mixture of Cd, Cu, Pb, and Zn and incubated for 12 months for aging. Microbial (Biolog Ecoplates) and enzyme activities (dehydrogenase, DHA; ß-galactosidase, BGAL; phosphatase, PHOS; and urease, URE) were assessed and related to metal availability and soil physicochemical parameters. All enzyme activities decreased significantly with metal contamination: 36-68 % (DHA), 24-85 % (BGAL), 22-72 % (PHOS), and 14-84 % (URE) inhibitions. Similarly, catabolic activity was negatively affected, especially phenol catabolism (∼86 % compared to 25-55 % inhibition for the rest of the substrates). Catabolic and DHA activities were negatively correlated with ethylenediaminetetraacetic acid (EDTA)-extractable Cd and Pb, but positively with CaCl2, NaNO3, and DTPA-extractable Cu and Zn. Soluble OM (water- and hot-water-soluble organic C) was positively related to enzyme and catabolic activities. Recalcitrant OM and fine mineral fractions were positively related to BGAL and PHOS. Conversely, catabolic activity was negatively related to clay and positively to silt and labile OM. Results indicate that the microbial response to metal contamination is highly affected by texture and OM composition.


Asunto(s)
Metales/toxicidad , Microbiología del Suelo , Contaminantes del Suelo/toxicidad , Suelo/química , Agricultura , Carbonato de Calcio/química , Ácido Edético , Contaminación Ambiental/estadística & datos numéricos , Metales/análisis , Tamaño de la Partícula , Contaminantes del Suelo/análisis , beta-Galactosidasa/metabolismo
6.
Environ Sci Pollut Res Int ; 20(9): 6392-405, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23589262

RESUMEN

A set of periurban calcareous agricultural Mediterranean soils was spiked with a mixture of Cd, Cu, Pb and Zn at two levels within the limit values proposed by current European legislation, incubated for up to 12 months, and subjected to various one-step extraction procedures to estimate mobile (neutral salts) and potentially mobile metal fractions (complexing and acidic extraction methods). The results obtained were used to study metal extractability patterns according to the soil characteristics. The analytical data were coupled with mineralogical investigations and speciation modelling using the Visual Minteq model. The formation of soluble metal-complexes in the complexing extracts (predicted by the Visual Minteq calculations) led to the highest extraction efficiency with complexing extractants. Metal extractability patterns were related to both content and composition of carbonate, organic matter, Fe oxide and clay fractions. Potentially mobile metal fractions were mainly affected by the finest soil fractions (recalcitrant organic matter, active lime and clay minerals). In the case of Pb, scarce correlations between extractable Pb and soil constituents were obtained which was attributed to high Pb retention due to the formation of 4PbCO3·3PbO (corroborated by X-ray diffraction). In summary, the high metal proportion extracted with complexing agents highlighted the high but finite capacity to store potentially mobilizable metals and the possible vulnerability of these soils against environmental impact from metal accumulation.


Asunto(s)
Metales/química , Contaminantes del Suelo/química , Suelo/química , Agricultura , Región Mediterránea
7.
Arch Environ Contam Toxicol ; 64(3): 388-98, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23183935

RESUMEN

Mediterranean climate characteristics and carbonate are key factors governing soil heavy-metal accumulation, and low organic matter (OM) content could limit the ability of microbial populations to cope with resulting stress. We studied the effects of metal contamination on a combination of biological parameters in soils having these characteristics. With this aim, soils were spiked with a mixture of cadmium, copper, lead, and zinc, at the two limit values proposed by current European legislation, and incubated for ≤12 months. Then we measured biochemical (phosphatase, urease, ß-galactosidase, arylsulfatase, and dehydrogenase activities) and microbial (fungal and bacterial DNA concentration by quantitative polymerase chain reaction) parameters. All of the enzyme activities were strongly affected by metal contamination and showed the following inhibition sequence: phosphatase (30-64 %) < arylsulfatase (38-97 %) ≤ urease (1-100 %) ≤ ß-galactosidase (30-100 %) < dehydrogenase (69-100 %). The high variability among soils was attributed to the different proportion of fine mineral fraction, OM, crystalline iron oxides, and divalent cations in soil solution. The decrease of fungal DNA concentration in metal-spiked soils was negligible, whereas the decrease of bacterial DNA was ~1-54 % at the lowest level and 2-69 % at the highest level of contamination. The lowest bacterial DNA decrease occurred in soils with the highest OM, clay, and carbonate contents. Finally, regarding the strong inhibition of the biological parameters measured and the alteration of the fungal/bacterial DNA ratio, we provide strong evidence that disturbance on the system, even within the limiting values of contamination proposed by the current European Directive, could alter key soil processes. These limiting values should be established according to soil characteristics and/or revised when contamination is produced by a mixture of heavy metals.


Asunto(s)
Agricultura , Sustancias Húmicas/análisis , Metales Pesados/toxicidad , Consorcios Microbianos/efectos de los fármacos , Microbiología del Suelo , Contaminantes del Suelo/toxicidad , Fenómenos Bioquímicos , Carbonatos/análisis , Fenómenos Químicos , Clima , Monitoreo del Ambiente , Enzimas/análisis , Región Mediterránea , Metales Pesados/análisis , Microbiología del Suelo/normas , Contaminantes del Suelo/análisis
8.
BMC Med Educ ; 12: 30, 2012 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-22587562

RESUMEN

BACKGROUND: The application of new technologies to the education of health professionals is both a challenge and a necessity. Virtual worlds are increasingly being explored as a support for education. AIM: The aim of this work is to study the suitability of Second Life (SL) as an educational tool for primary healthcare professionals. DESIGN: Qualitative study of accredited clinical sessions in SL included in a continuing professional development (CPD) programme for primary healthcare professionals. LOCATION: Zaragoza I Zone Family and Community Medicine Education Unit (EU) and 9 health centres operated by the Aragonese Health Service, Aragon, Spain. METHOD: The EU held two training workshops in SL for 16 healthcare professionals from 9 health centres by means of two workshops, and requested them to facilitate clinical sessions in SL. Attendance was open to all personnel from the EU and the 9 health centres. After a trail period of clinical sessions held at 5 health centres between May and November 2010, the CPD-accredited clinical sessions were held at 9 health centres between February and April 2011. PARTICIPANTS: 76 healthcare professionals attended the CPD-accredited clinical sessions in SL. MAIN MEASUREMENTS: Questionnaire on completion of the clinical sessions. RESULTS: Response rate: 42-100%. Questionnaire completed by each health centre on completion of the CPD-accredited clinical sessions: Access to SL: 2 centres were unable to gain access. Sound problems: 0% (0/9). Image problems: 0% (0/9). Voice/text chat: used in 100% (10/9); 0 incidents. Questionnaire completed by participants in the CPD-accredited clinical sessions: Preference for SL as a tool: 100% (76/76). Strengths of this method: 74% (56/76) considered it eliminated the need to travel; 68% (52/76) believed it made more effective use of educational resources; and 47% (36/76) considered it improved accessibility. Weaknesses: 91% (69/76) experienced technical problems, while; 9% (7/76) thought it was impersonal and with little interaction. 65.79% (50/76) believed it was better than other distance learning methods and 38.16% (29/76) believed it was better than face-to-face learning. CONCLUSIONS: SL is a tool that allows educational activities to be designed that involve a number of health centres in different geographical locations, consequently eliminating the need to travel and making more effective use of educational resources.


Asunto(s)
Medicina Comunitaria/educación , Instrucción por Computador/métodos , Educación Médica Continua/métodos , Medicina Familiar y Comunitaria/educación , Interfaz Usuario-Computador , Acreditación , Actitud del Personal de Salud , Actitud hacia los Computadores , Curriculum , Educación , Humanos , Programas Informáticos , Encuestas y Cuestionarios
9.
Int J Psychiatry Clin Pract ; 15(1): 62-8, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22122691

RESUMEN

OBJECTIVE: This study identified predictors of psychosocial outcome in schizophrenia. METHOD: A mixed group of patients diagnosed with schizophrenia were assessed as part of a routine clinical evaluation. A linear regression analysis was conducted in order to examine the effect of duration of untreated illness, number of previous hospitalisations, history of psychotic episodes and age at illness onset on patients' functioning, as assessed with the Global Assessment of Functioning (GAF) scale. RESULTS: Number of previous psychotic episodes as well as duration of untreated illness were the strongest predictors of patients' levels of functioning amongst all main outcome measures. Older age at illness onset also predicted poorer functioning. Limitations. A principal limitation of our study is that our sample included predominantly Caucasian males; therefore, any extrapolation to other groups may remain speculative. CONCLUSIONS: Our preliminary results suggest that psychosocial outcome in schizophrenia may be affected by different factors. Longer history of psychotic episodes emerged as the most significant determinant of poorer outcome while longer duration of untreated illness and older age at illness onset were also associated with detrimental effects. Our findings may reflect the combined influences of neurodevelopmental abnormalities, exposure to psychotropic medication and psychosocial interventions as well as the vicissitudes of natural aging processes embedded in a chronic mental illness.


Asunto(s)
Trastornos Psicóticos/complicaciones , Esquizofrenia/complicaciones , Psicología del Esquizofrénico , Adolescente , Adulto , Edad de Inicio , Hospitalización , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Pronóstico , Escalas de Valoración Psiquiátrica , Trastornos Psicóticos/epidemiología , Adulto Joven
10.
Psychiatr Q ; 80(3): 155-65, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19526340

RESUMEN

To explore whether cognitive impairment and global functioning can predict the degree of insight into illness as well as whether insight is mediated by specific symptom dimensions of psychopathology in schizophrenia. A dimensional/cross sectional approach was used. A mixed group of clients (n = 36) were assessed as part of a routine clinical evaluation. The Wechsler Adult Intelligence Scale (WAIS) was used as a measure of intellectual performance, the Brief Symptom Inventory (BSI) was used as a measure of general psychopathology while the Global Assessment of Functioning (GAF) scale assessed clients' psychosocial functioning; insight was assessed with the Insight and Treatment Attitudes Questionnaire (ITAQ). The correlation matrix of all outcome variables was examined; confounding effects of illness duration were tested by partial correlation analyses. GAF correlated with insight (rho = 0.41, P = 0.01) and the interpersonal sensitivity dimension of BSI (rho = -0.38, P = 0.03. Insight correlated positively with the anxiety (rho = 0.38, P = 0.03) and psychoticism (rho = 0.36, P = 0.04) dimensions of BSI. Our results suggest that insight is part of the phenomenology in schizophrenia, not being determined by neurocognitive disturbances. Improved insight was associated with more frequent psychotic symptoms endorsement, higher levels of anxiety and less severe psychopathological symptoms and difficulties in psychosocial functioning; clients with more pronounced difficulties in their personal and social interactions exhibited worse psychosocial functioning and more severe psychopathological symptoms.


Asunto(s)
Actitud Frente a la Salud , Cognición , Esquizofrenia/diagnóstico , Psicología del Esquizofrénico , Adulto , Estudios de Cohortes , Femenino , Humanos , Relaciones Interpersonales , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Calidad de Vida , Índice de Severidad de la Enfermedad , Conducta Social
11.
J Org Chem ; 68(21): 8120-8, 2003 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-14535793

RESUMEN

Nanometer-sized conjugated 1,4- and 1,3,5-ethynylphenyl oligomers were synthesized starting from 3,5-di(trimethylsilylethynyl)phenylacetylene and p-[3,5-di(trimethylsilylethynyl)-1-ethynylphenyl]phenyl acetylene by cross-coupling reaction with a convenient haloaryl derivative, catalyzed by palladium(II)/copper(I), in excellent yield. The terminal acetylenes were efficiently prepared by a specific protection-deprotection methodology. All ethynylphenyl homologues obtained show fluorescence emission, with the bathochromic shift of approximately 20 nm by each ethynylphenyl unit increasing the conjugate chain. Parallel conjugated ethynylphenyl chains were prepared through the insertion of a 1,5-naphthalene subunit, and the compounds exhibit fluorescence radiation emission.

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